''Pseudomonas'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
Gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...
,
Gammaproteobacteria, belonging to the family
Pseudomonadaceae
The Pseudomonadaceae are a family of bacteria which includes the genera ''Azomonas'', ''Azorhizophilus'', ''Azotobacter'', '' Mesophilobacter'', ''Pseudomonas'' (the type genus), and '' Rugamonas''. The family Azotobacteraceae was recently recl ...
and containing 191 described species.
The members of the genus demonstrate a great deal of
metabolic
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...
diversity and consequently are able to colonize a wide range of niches.
Their ease of culture ''
in vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...
'' and availability of an increasing number of ''Pseudomonas'' strain
genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...
sequences has made the genus an excellent focus for scientific research; the best studied species include ''
P. aeruginosa P. is an abbreviation or acronym that may refer to:
* Page (paper), where the abbreviation comes from Latin ''pagina''
* Paris Herbarium, at the ''Muséum national d'histoire naturelle''
* ''Pani'' (Polish), translating as Mrs.
* The ''Pacific Repo ...
'' in its role as an opportunistic
human pathogen A human pathogen is a pathogen (microbe or microorganism such as a virus, bacterium, prion, or fungus) that causes disease in humans.
The human physiological defense against common pathogens (such as ''Pneumocystis'') is mainly the responsibility ...
, the plant pathogen ''
P. syringae'', the soil bacterium ''
P. putida'', and the plant growth-promoting ''
P. fluorescens
''Pseudomonas fluorescens'' is a common Gram-negative, rod-shaped bacterium. It belongs to the ''Pseudomonas'' genus; 16S ribosomal RNA, 16S rRNA analysis as well as phylogenomic analysis has placed ''P. fluorescens'' in the ''P. fluorescens'' gr ...
,
P. lini,
P. migulae'', and ''P. graminis''.
Because of their widespread occurrence in water and plant seeds such as
dicots, the
pseudomonads were observed early in the history of
microbiology
Microbiology () is the scientific study of microorganisms, those being unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). Microbiology encompasses numerous sub-disciplines including virology, bacteriology, prot ...
. The generic name ''Pseudomonas'' created for these organisms was defined in rather vague terms by
Walter Migula
Emil Friedrich August Walter (or Walther) Migula (born 1863 in Żyrowa, Poland; died 1938 in Eisenach, Germany) was a Poland-born German botanist.
In 1890, he was habilitated for botany at Karlsruhe Institute of Technology, where he spent sev ...
in 1894 and 1900 as a genus of Gram-negative, rod-shaped, and polar-
flagella
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates.
A microorganism may have f ...
ted bacteria with some sporulating species.
[Migula, W. (1894) Über ein neues System der Bakterien. Arb Bakteriol Inst Karlsruhe 1: 235–238.][Migula, W. (1900) System der Bakterien, Vol. 2. Jena, Germany: Gustav Fischer.] The latter statement was later proved incorrect and was due to refractive granules of reserve materials.
Despite the vague description, the type species, ''Pseudomonas pyocyanea'' (basonym of ''
Pseudomonas aeruginosa
''Pseudomonas aeruginosa'' is a common encapsulated, gram-negative, aerobic–facultatively anaerobic, rod-shaped bacterium that can cause disease in plants and animals, including humans. A species of considerable medical importance, ''P. aerugi ...
''), proved the best descriptor.
[
]
Classification history
Like most bacterial genera, the pseudomonad[ ]last common ancestor
In biology and genetic genealogy, the most recent common ancestor (MRCA), also known as the last common ancestor (LCA) or concestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended. The ...
lived hundreds of millions of years ago. They were initially classified at the end of the 19th century when first identified by Walter Migula
Emil Friedrich August Walter (or Walther) Migula (born 1863 in Żyrowa, Poland; died 1938 in Eisenach, Germany) was a Poland-born German botanist.
In 1890, he was habilitated for botany at Karlsruhe Institute of Technology, where he spent sev ...
. The etymology of the name was not specified at the time and first appeared in the seventh edition of '' Bergey's Manual of Systematic Bacteriology'' (the main authority in bacterial nomenclature) as Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
''pseudes ''(ψευδής) "false" and '' -monas'' (μονάς/μονάδος) "a single unit", which can mean false unit; however, Migula possibly intended it as false ''Monas
The National Monument ( id, Monumen Nasional, abbreviated Monas) is a 132 m (433 ft) obelisk in the centre of Merdeka Square, Central Jakarta, symbolizing the fight for Indonesia. It is the national monument of the Republic of Indones ...
'', a nanoflagellated protist[ (subsequently, the term "monad" was used in the early history of microbiology to denote unicellular organisms). Soon, other species matching Migula's somewhat vague original description were isolated from many natural niches and, at the time, many were assigned to the ]genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
. However, many strains have since been reclassified, based on more recent methodology and use of approaches involving studies of conservative macromolecules.
Recently, 16S rRNA sequence analysis has redefined the taxonomy of many bacterial species. As a result, the genus ''Pseudomonas'' includes strains formerly classified in the genera ''Chryseomonas'' and ''Flavimonas''. Other strains previously classified in the genus ''Pseudomonas'' are now classified in the genera ''Burkholderia
''Burkholderia'' is a genus of Pseudomonadota whose pathogenic members include the ''Burkholderia cepacia'' complex, which attacks humans and ''Burkholderia mallei'', responsible for glanders, a disease that occurs mostly in horses and related ...
'' and ''Ralstonia
''Ralstonia'' is a genus of bacteria, previously included in the genus ''Pseudomonas''. It is named after the American bacteriologist Ericka Ralston. Ericka Ralston was born Ericka Barrett in 1944 in Saratoga, California, and died in 2015 in Seb ...
''.
In 2020, a phylogenomic analysis of 494 complete ''Pseudomonas'' genomes identified two well-defined species (''P. aeruginosa'' and ''P. chlororaphis'') and four wider phylogenetic groups (''P. fluorescens, P. stutzeri, P. syringae, P. putida'') with a sufficient number of available proteomes. The four wider evolutionary groups include more than one species, based on species definition by the Average Nucleotide Identity levels. In addition, the phylogenomic analysis identified several strains that were mis-annotated to the wrong species or evolutionary group. This mis-anotation problem has been reported by other analyses as well.
Genomics
In 2000, the complete genome sequence
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding g ...
of a ''Pseudomonas'' species was determined; more recently, the sequence of other strains has been determined, including ''P. aeruginosa'' strains PAO1 (2000), ''P. putida'' KT2440 (2002), ''P. protegens'' Pf-5 (2005), ''P. syringae'' pathovar tomato DC3000 (2003), ''P. syringae'' pathovar syringae B728a (2005), ''P. syringae'' pathovar phaseolica 1448A (2005), ''P. fluorescens'' Pf0-1, and ''P. entomophila'' L48.
By 2016, more than 400 strains of ''Pseudomonas'' had been sequenced. Sequencing the genomes of hundreds of strains revealed highly divergent species within the genus. In fact, many genomes of ''Pseudomonas'' share only 50-60% of their genes, e.g. ''P. aeruginosa P. is an abbreviation or acronym that may refer to:
* Page (paper), where the abbreviation comes from Latin ''pagina''
* Paris Herbarium, at the ''Muséum national d'histoire naturelle''
* ''Pani'' (Polish), translating as Mrs.
* The ''Pacific Repo ...
'' and '' P. putida'' share only 2971 proteins out of 5350 (or ~55%).
By 2020, more than 500 complete ''Pseudomonas'' genomes were available in Genebank. A phylogenomic analysis utilized 494 complete proteomes and identified 297 core orthologues, shared by all strains. This set of core orthologues at the genus level was enriched for proteins involved in metabolism, translation, and transcription and was utilized for generating a phylogenomic tree of the entire genus, to delineate the relationships among the ''Pseudomonas'' major evolutionary groups. In addition, group-specific core proteins were identified for most evolutionary groups, meaning that they were present in all members of the specific group, but absent in other pseudomonads. For example, several ''P. aeruginosa''-specific core proteins were identified that are known to play an important role in this species' pathogenicity, such as ''CntL, CntM, PlcB, Acp1, MucE, SrfA, Tse1, Tsi2, Tse3,'' and ''EsrC''.
Characteristics
Members of the genus display these defining characteristics:
* Rod-shaped
A bacillus (), also called a bacilliform bacterium or often just a rod (when the context makes the sense clear), is a rod-shaped bacterium or archaeon. Bacilli are found in many different taxonomic groups of bacteria. However, the name '' Baci ...
* Gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...
* Flagellum
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates.
A microorganism may have f ...
one or more, providing motility
Motility is the ability of an organism to move independently, using metabolic energy.
Definitions
Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ...
* Aerobic
Aerobic means "requiring air," in which "air" usually means oxygen.
Aerobic may also refer to
* Aerobic exercise, prolonged exercise of moderate intensity
* Aerobics, a form of aerobic exercise
* Aerobic respiration, the aerobic process of cel ...
* Non-spore forming
* Catalase-positive
* Oxidase-positive
Other characteristics that tend to be associated with ''Pseudomonas'' species (with some exceptions) include secretion of pyoverdine
Pyoverdines (alternatively, and less commonly, spelled as pyoverdins) are fluorescent siderophores produced by certain pseudomonads. Pyoverdines are important virulence factors, and are required for pathogenesis in many biological models of inf ...
, a fluorescent
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, tha ...
yellow-green siderophore
Siderophores (Greek: "iron carrier") are small, high-affinity iron- chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is n ...
under iron-limiting conditions. Certain ''Pseudomonas'' species may also produce additional types of siderophore, such as pyocyanin
Pyocyanin (PCN−) is one of the many toxic compounds produced and secreted by the Gram negative bacterium ''Pseudomonas aeruginosa''. Pyocyanin is a blue secondary metabolite, turning red below pH 4.9, with the ability to oxidise and reduce other ...
by ''Pseudomonas aeruginosa
''Pseudomonas aeruginosa'' is a common encapsulated, gram-negative, aerobic–facultatively anaerobic, rod-shaped bacterium that can cause disease in plants and animals, including humans. A species of considerable medical importance, ''P. aerugi ...
'' and thioquinolobactin by '' Pseudomonas fluorescens'',. ''Pseudomonas'' species also typically give a positive result to the oxidase test
The oxidase test is used to determine if an organism possesses the cytochrome c oxidase enzyme. The test is used as an aid for the differentiation of ''Neisseria'', ''Moraxella'', '' Campylobacter'' and ''Pasteurella'' species (oxidase positive). I ...
, the absence of gas formation from glucose, glucose is oxidised in oxidation/fermentation test using Hugh and Leifson O/F test, beta hemolytic
Hemolysis or haemolysis (), also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid (e.g. blood plasma). Hemolysis may occur in vivo o ...
(on blood agar), indole
Indole is an aromatic heterocyclic organic compound with the formula C8 H7 N. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered pyrrole ring. Indole is widely distributed in the natural environmen ...
negative, methyl red
Methyl red (2-(''N'',''N''-dimethyl-4-aminophenyl) azobenzenecarboxylic acid), also called C.I. Acid Red 2, is an indicator dye that turns red in acidic solutions. It is an azo dye, and is a dark red crystalline powder. Methyl red is a pH indica ...
negative, Voges–Proskauer test negative, and citrate
Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in the ...
positive.
''Pseudomonas'' may be the most common nucleator of ice crystals in clouds, thereby being of utmost importance to the formation of snow and rain around the world.
Biofilm formation
All species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
and strains of ''Pseudomonas'' have historically been classified as strict aerobes. Exceptions to this classification have recently been discovered in ''Pseudomonas'' biofilms
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular po ...
. A significant number of cells can produce exopolysaccharides associated with biofilm formation. Secretion of exopolysaccharide
Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental comp ...
s such as alginate makes it difficult for pseudomonads to be phagocytose
Phagocytosis () is the process by which a cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome. It is one type of endocytosis. A cell that performs phagocytosis is ...
d by mammalian white blood cells
White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...
. Exopolysaccharide production also contributes to surface-colonising biofilm
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...
s that are difficult to remove from food preparation surfaces. Growth of pseudomonads on spoiling foods can generate a "fruity" odor.
Antibiotic resistance
Most ''Pseudomonas'' spp. are naturally resistant to penicillin
Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum using ...
and the majority of related beta-lactam antibiotics
β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their chemical
structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and ...
, but a number are sensitive to piperacillin
Piperacillin is a broad-spectrum β-lactam antibiotic of the ureidopenicillin class. The chemical structure of piperacillin and other ureidopenicillins incorporates a polar side chain that enhances penetration into Gram-negative bacteria and red ...
, imipenem
Imipenem (trade name Primaxin among others) is an intravenous β-lactam antibiotic discovered by Merck scientists Burton Christensen, William Leanza, and Kenneth Wildonger in the mid-1970s. Carbapenems are highly resistant to the β-lactamase enz ...
, ticarcillin
Ticarcillin is a carboxypenicillin. It can be sold and used in combination with clavulanate as ticarcillin/clavulanic acid. Because it is a penicillin, it also falls within the larger class of beta-lactam antibiotics. Its main clinical use is as ...
, or ciprofloxacin
Ciprofloxacin is a fluoroquinolone antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra abdominal infections, certain types of infectious diarrhea, respiratory tract infections, skin inf ...
. Aminoglycosides such as tobramycin
Tobramycin is an aminoglycoside antibiotic derived from '' Streptomyces tenebrarius'' that is used to treat various types of bacterial infections, particularly Gram-negative infections. It is especially effective against species of ''Pseudomonas ...
, gentamicin
Gentamicin is an antibiotic used to treat several types of bacterial infections. This may include bone infections, endocarditis, pelvic inflammatory disease, meningitis, pneumonia, urinary tract infections, and sepsis among others. It is not e ...
, and amikacin
Amikacin is an antibiotic medication used for a number of bacterial infections. This includes joint infections, intra-abdominal infections, meningitis, pneumonia, sepsis, and urinary tract infections. It is also used for the treatment of mu ...
are other choices for therapy.
This ability to thrive in harsh conditions is a result of their hardy cell wall
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mech ...
s that contain porins. Their resistance to most antibiotics is attributed to efflux pumps, which pump out some antibiotics before they are able to act.
''Pseudomonas aeruginosa
''Pseudomonas aeruginosa'' is a common encapsulated, gram-negative, aerobic–facultatively anaerobic, rod-shaped bacterium that can cause disease in plants and animals, including humans. A species of considerable medical importance, ''P. aerugi ...
'' is increasingly recognized as an emerging opportunistic pathogen
An opportunistic infection is an infection caused by pathogens (bacteria, fungi, parasites or viruses) that take advantage of an opportunity not normally available. These opportunities can stem from a variety of sources, such as a weakened immune ...
of clinical relevance. One of its most worrying characteristics is its low antibiotic susceptibility. This low susceptibility is attributable to a concerted action of multidrug efflux pumps with chromosomally encoded antibiotic resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. ...
genes (e.g., ''mexAB-oprM'', ''mexXY'', etc.,) and the low permeability of the bacterial cellular envelopes. Besides intrinsic resistance, ''P. aeruginosa'' easily develops acquired resistance either by mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mi ...
in chromosomally encoded genes or by the horizontal gene transfer
Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between Unicellular organism, unicellular and/or multicellular organisms other than by the ("vertical") transmission of DNA from parent to offsprin ...
of antibiotic resistance determinants. Development of multidrug resistance
Multiple drug resistance (MDR), multidrug resistance or multiresistance is antimicrobial resistance shown by a species of microorganism to at least one antimicrobial drug in three or more antimicrobial categories. Antimicrobial categories are c ...
by ''P. aeruginosa'' isolates requires several different genetic events that include acquisition of different mutations and/or horizontal transfer of antibiotic resistance genes. Hypermutation favours the selection of mutation-driven antibiotic resistance in ''P. aeruginosa'' strains producing chronic infections, whereas the clustering of several different antibiotic resistance genes in integron Integrons are genetic mechanisms that allow bacteria to adapt and evolve rapidly through the stockpiling and expression of new genes. These genes are embedded in a specific genetic structure called gene cassette (a term that is lately changing to in ...
s favours the concerted acquisition of antibiotic resistance determinants. Some recent studies have shown phenotypic resistance associated to biofilm
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...
formation or to the emergence of small-colony-variants, which may be important in the response of ''P. aeruginosa'' populations to antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...
treatment.
Sensitivity to Gallium
Although gallium
Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group (aluminiu ...
has no natural function in biology, gallium ions interact with cellular processes in a manner similar to iron(III). When gallium ions are mistakenly taken up in place of iron(III) by bacteria such as ''Pseudomonas'', the ions interfere with respiration, and the bacteria die. This happens because iron is redox-active, allowing the transfer of electrons during respiration, while gallium is redox-inactive.
Pathogenicity
Animal Pathogens
Infectious species include ''P. aeruginosa P. is an abbreviation or acronym that may refer to:
* Page (paper), where the abbreviation comes from Latin ''pagina''
* Paris Herbarium, at the ''Muséum national d'histoire naturelle''
* ''Pani'' (Polish), translating as Mrs.
* The ''Pacific Repo ...
'', '' P. oryzihabitans'', and '' P. plecoglossicida''. ''P. aeruginosa'' flourishes in hospital environments, and is a particular problem in this environment, since it is the second-most common infection in hospitalized patients (nosocomial infection
A hospital-acquired infection, also known as a nosocomial infection (from the Greek , meaning "hospital"), is an infection that is acquired in a hospital or other health care facility. To emphasize both hospital and nonhospital settings, it is so ...
s). This pathogenesis may in part be due to the proteins secreted by ''P. aeruginosa''. The bacterium possesses a wide range of secretion systems, which export numerous proteins relevant to the pathogenesis of clinical strains. Intriguingly, several genes involved in the pathogenesis of ''P.aeruginosa,'' such as ''CntL, CntM, PlcB, Acp1, MucE, SrfA, Tse1, Tsi2, Tse3,'' and ''EsrC'' are core group-specific, meaning that they are shared by the vast majority of ''P. aeruginosa'' strains, but they are not present in other ''Pseudomonads''.
Plant Pathogens
''P. syringae'' is a prolific plant pathogen
Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomyc ...
. It exists as over 50 different pathovar
A pathovar is a bacterial strain or set of strains with the same or similar characteristics, that is differentiated at infrasubspecific level from other strains of the same species or subspecies on the basis of distinctive pathogenicity to one o ...
s, many of which demonstrate a high degree of host-plant specificity. Numerous other ''Pseudomonas'' species can act as plant pathogens, notably all of the other members of the ''P. syringae'' subgroup, but ''P. syringae'' is the most widespread and best-studied.
Although not strictly a plant pathogen, '' P. tolaasii'' can be a major agricultural problem, as it can cause bacterial blotch of cultivated mushrooms
A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans.
The standard for the na ...
. Similarly, '' P. agarici'' can cause drippy gill in cultivated mushrooms.
Use as Biocontrol Agents
Since the mid-1980s, certain members of the genus ''Pseudomonas'' have been applied to cereal seeds or applied directly to soils as a way of preventing the growth or establishment of crop pathogens. This practice is generically referred to as biocontrol
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
. The biocontrol properties of ''P. fluorescens'' and '' P. protegens'' strains (CHA0 or Pf-5 for example) are currently best-understood, although it is not clear exactly how the plant growth-promoting properties of ''P. fluorescens'' are achieved. Theories include: the bacteria might induce systemic resistance in the host plant, so it can better resist attack by a true pathogen; the bacteria might outcompete other (pathogenic) soil microbes, e.g. by siderophore
Siderophores (Greek: "iron carrier") are small, high-affinity iron- chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is n ...
s giving a competitive advantage at scavenging for iron; the bacteria might produce compounds antagonistic to other soil microbes, such as phenazine
Phenazine is an organic compound with the formula (C6H4)2N2. It is a dibenzo annulated pyrazine, and the parent substance of many dyestuffs, such as the toluylene red, indulines, and safranines (and the closely related eurhodines). Phenazine ...
-type antibiotics or hydrogen cyanide
Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an ...
. Experimental evidence supports all of these theories.
Other notable ''Pseudomonas'' species with biocontrol properties include '' P. chlororaphis'', which produces a phenazine
Phenazine is an organic compound with the formula (C6H4)2N2. It is a dibenzo annulated pyrazine, and the parent substance of many dyestuffs, such as the toluylene red, indulines, and safranines (and the closely related eurhodines). Phenazine ...
-type antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...
active agent against certain fungal
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...
plant pathogens, and the closely related species '' P. aurantiaca'', which produces di-2,4-diacetylfluoroglucylmethane, a compound antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...
ally active against Gram-positive
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall.
Gram-positive bacte ...
organisms.
Use as Bioremediation Agents
Some members of the genus are able to metabolise chemical pollutants in the environment, and as a result, can be used for bioremediation
Bioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi, and plants), living or dead, is employed for removing environmental pollutants from air, water, soil, flue gasses, industrial effluent ...
. Notable species demonstrated as suitable for use as bioremediation agents include:
* '' P. alcaligenes'', which can degrade polycyclic aromatic hydrocarbon
A polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. The simplest representative is naphthalene, having two aromatic rings and the three-ring compounds anthracene and phenanthrene. ...
s.
* '' P. mendocina'', which is able to degrade toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) a ...
.
* '' P. pseudoalcaligenes'', which is able to use cyanide
Cyanide is a naturally occurring, rapidly acting, toxic chemical that can exist in many different forms.
In chemistry, a cyanide () is a chemical compound that contains a functional group. This group, known as the cyano group, consists of ...
as a nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
source.
* '' P. resinovorans'', which can degrade carbazole
Carbazole is an aromatic heterocyclic organic compound. It has a tricyclic structure, consisting of two six-membered benzene rings fused on either side of a five-membered nitrogen-containing ring. The compound's structure is based on the indole str ...
.
*''P. aeruginosa P. is an abbreviation or acronym that may refer to:
* Page (paper), where the abbreviation comes from Latin ''pagina''
* Paris Herbarium, at the ''Muséum national d'histoire naturelle''
* ''Pani'' (Polish), translating as Mrs.
* The ''Pacific Repo ...
'', '' P. putida'', ''P. desmolyticum'', and ''P. nitroreducens'' can degrade chlorpyrifos
Chlorpyrifos (CPS), also known as Chlorpyrifos ethyl, is an organophosphate pesticide that has been used on crops, animals, and buildings, and in other settings, to kill several pests, including insects and worms. It acts on the nervous systems ...
.
* '' P. veronii'', which has been shown to degrade a variety of simple aromatic
In chemistry, aromaticity is a chemical property of cyclic ( ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to satur ...
organic compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...
s.
* '' P. putida'', which has the ability to degrade organic solvents such as toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) a ...
. At least one strain of this bacterium is able to convert morphine
Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ...
in aqueous solution into the stronger and somewhat expensive to manufacture drug hydromorphone
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mou ...
(Dilaudid).
* Strain KC of '' P. stutzeri'', which is able to degrade carbon tetrachloride
Carbon tetrachloride, also known by many other names (such as tetrachloromethane, also IUPAC nomenclature of inorganic chemistry, recognised by the IUPAC, carbon tet in the cleaning industry, Halon-104 in firefighting, and Refrigerant-10 in HVAC ...
.
Detection of Food Spoilage Agents in Milk
One way of identifying and categorizing multiple bacterial organisms in a sample is to use ribotyping. In ribotyping, differing lengths of chromosomal DNA are isolated from samples containing bacterial species, and digested into fragments. Similar types of fragments from differing organisms are visualized and their lengths compared to each other by Southern blotting or by the much faster method of polymerase chain reaction (PCR)
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it (or a part of it) ...
. Fragments can then be matched with sequences found on bacterial species. Ribotyping is shown to be a method to isolate bacteria capable of spoilage. Around 51% of ''Pseudomonas'' bacteria found in dairy processing plants are ''P. fluorescens
''Pseudomonas fluorescens'' is a common Gram-negative, rod-shaped bacterium. It belongs to the ''Pseudomonas'' genus; 16S ribosomal RNA, 16S rRNA analysis as well as phylogenomic analysis has placed ''P. fluorescens'' in the ''P. fluorescens'' gr ...
'', with 69% of these isolates possessing proteases, lipases, and lecithinases which contribute to degradation of milk components and subsequent spoilage. Other ''Pseudomonas'' species can possess any one of the proteases, lipases, or lecithinases, or none at all. Similar enzymatic activity is performed by ''Pseudomonas'' of the same ribotype, with each ribotype showing various degrees of milk spoilage and effects on flavour. The number of bacteria affects the intensity of spoilage, with non-enzymatic ''Pseudomonas'' species contributing to spoilage in high number.
Food spoilage is detrimental to the food industry due to production of volatile compounds from organisms metabolizing the various nutrients found in the food product. Contamination results in health hazards from toxic compound production as well as unpleasant odours and flavours. Electronic nose technology allows fast and continuous measurement of microbial food spoilage by sensing odours produced by these volatile compounds. Electronic nose technology can thus be applied to detect traces of ''Pseudomonas'' milk spoilage and isolate the responsible ''Pseudomonas'' species. The gas sensor consists of a nose portion made of 14 modifiable polymer sensors that can detect specific milk degradation products produced by microorganisms. Sensor data is produced by changes in electric resistance of the 14 polymers when in contact with its target compound, while four sensor parameters can be adjusted to further specify the response. The responses can then be pre-processed by a neural network which can then differentiate between milk spoilage microorganisms such as ''P. fluorescens
''Pseudomonas fluorescens'' is a common Gram-negative, rod-shaped bacterium. It belongs to the ''Pseudomonas'' genus; 16S ribosomal RNA, 16S rRNA analysis as well as phylogenomic analysis has placed ''P. fluorescens'' in the ''P. fluorescens'' gr ...
'' and '' P. aureofaciens''.
Species
''Pseudomonas'' comprises the following species, organized into genomic affinity groups:
''P. aeruginosa'' Group
* ''P. aeruginosa P. is an abbreviation or acronym that may refer to:
* Page (paper), where the abbreviation comes from Latin ''pagina''
* Paris Herbarium, at the ''Muséum national d'histoire naturelle''
* ''Pani'' (Polish), translating as Mrs.
* The ''Pacific Repo ...
'' (Schroeter 1872) Migula 1900 (Approved Lists 1980)
* '' P. citronellolis'' Seubert 1960 (Approved Lists 1980)
* '' P. delhiensis'' Prakash et al. 2007
* "'' P. denitrificans''" Bergey et al. 1961
* '' P. jinjuensis'' Kwon et al. 2003
* '' P. knackmussii'' Stolz et al. 2007
* '' P. nicosulfuronedens'' Li et al. 2021
* '' P. nitroreducens'' Iizuka and Komagata 1964 (Approved Lists 1980)
* '' P. panipatensis'' Gupta et al. 2008
''P. anguilliseptica'' Group
* '' P. anguilliseptica'' Wakabayashi and Egusa 1972 (Approved Lists 1980)
* '' P. benzenivorans'' Lang et al. 2012
* '' P. borbori'' Vanparys et al. 2006
* '' P. campi'' Timsy et al. 2021
* '' P. cuatrocienegasensis'' Escalante et al. 2009
* '' P. glareae'' Romanenko et al. 2015
* '' P. guineae'' Bozal et al. 2007
* '' P. guryensis'' Kim et al. 2021
* '' P. lalucatii'' Busquets et al. 2021
* '' P. leptonychotis'' Nováková et al. 2020
* '' P. marincola'' Romanenko et al. 2008
* '' P. peli'' Vanparys et al. 2006
* '' P. segitis'' Park et al. 2006
* '' P. taeanensis'' Lee et al. 2010
* '' P. ullengensis'' Kim et al. 2021
''P. fluorescens'' Group
''P. asplenii'' Subgroup
* '' P. agarici'' Young 1970 (Approved Lists 1980)
* '' P. asplenii'' (Ark and Tompkins 1946) Savulescu 1947 (Approved Lists 1980)
* "'' P. batumici''" Kiprianova et al. 2011
* '' P. fuscovaginae'' (ex Tanii et al. 1976) Miyajima et al. 1983
* "'' P. gingeri''" Cutri et al. 1984
* '' P. vanderleydeniana'' Girard et al. 2022
''P. chlororaphis'' Subgroup
* '' P. aurantiaca'' Nakhimovskaya 1948 (Approved Lists 1980)
* '' P. aureofaciens'' Kluyver 1956 (Approved Lists 1980)
* '' P. chlororaphis'' (Guignard and Sauvageau 1894) Bergey et al. 1930 (Approved Lists 1980)
* "'' P. piscium''" (Burr et al. 2010) Chen et al. 2018
''P. corrugata'' Subgroup
* '' P. alvandae'' Girard et al. 2022
* '' P. bijieensis'' Liang et al. 2021
* '' P. brassicacearum'' Achouak et al. 2000
* '' P. canavaninivorans'' Hauth et al. 2022
* '' P. corrugata'' Roberts and Scarlett 1981
* '' P. kilonensis'' Sikorski et al. 2001
* '' P. marvdashtae'' Girard et al. 2022
* '' P. mediterranea'' Catara et al. 2002
* '' P. ogarae'' Garrido-Sanz et al. 2022
* '' P. tehranensis'' Girard et al. 2022
* '' P. thivervalensis'' Achouak et al. 2000
* '' P. viciae'' Zhao et al. 2020
* '' P. zanjanensis'' Girard et al. 2022
* '' P. zarinae'' Girard et al. 2022
''P. fluorescens'' Subgroup
* '' P. allii'' Sawada et al. 2021
* '' P. antarctica'' Reddy et al. 2004
* '' P. asgharzadehiana'' Girard et al. 2022
* '' P. aylmerensis'' corrig. Tchagang et al. 2021
* '' P. azadiae'' Girard et al. 2022
* '' P. azotoformans'' Iizuka and Komagata 1963 (Approved Lists 1980)
* '' P. canadensis'' Tambong et al. 2017
* '' P. carnis'' Lick et al. 2020
* '' P. cedrina'' corrig. Dabboussi et al. 2002
* '' P. costantinii'' Munsch et al. 2002
* '' P. cremoris'' Hofmann et al. 2021
* '' P. cyclaminis'' Sawada et al. 2021
* '' P. edaphica'' Ramírez-Bahena et al. 2019
* '' P. extremaustralis'' López et al. 2010
* '' P. extremorientalis'' Ivanova et al. 2002
* '' P. fildesensis'' Pavlov et al. 2020
* ''P. fluorescens
''Pseudomonas fluorescens'' is a common Gram-negative, rod-shaped bacterium. It belongs to the ''Pseudomonas'' genus; 16S ribosomal RNA, 16S rRNA analysis as well as phylogenomic analysis has placed ''P. fluorescens'' in the ''P. fluorescens'' gr ...
'' Migula 1895 (Approved Lists 1980)
* "'' P. fulgida''" Naureen et al. 2005
* '' P. grimontii'' Baïda et al. 2002
* '' P. haemolytica'' Hofmann et al. 2020
* '' P. kairouanensis'' Oueslati et al. 2020
* '' P. karstica'' Švec et al. 2020
* '' P. khavaziana'' Girard et al. 2022
* '' P. kitaguniensis'' Sawada et al. 2020
* '' P. lactis'' von Neubeck et al. 2017
* '' P. lactucae'' Sawada et al. 2021
* '' P. libanensis'' Dabboussi et al. 1999
* '' P. lurida'' Behrendt et al. 2007
* '' P. marginalis'' (Brown 1918) Stevens 1925 (Approved Lists 1980)
* '' P. nabeulensis'' Oueslati et al. 2020
* '' P. orientalis'' Dabboussi et al. 2002
* '' P. palleroniana'' Gardan et al. 2002
* '' P. panacis'' Park et al. 2005
* '' P. paracarnis'' Lick et al. 2021
* '' P. paralactis'' von Neubeck et al. 2017
* '' P. pisciculturae'' Duman et al. 2021
* '' P. poae'' Behrendt et al. 2003
* '' P. rhodesiae'' Coroler et al. 1997
* '' P. salmasensis'' Girard et al. 2022
* '' P. salomonii'' Gardan et al. 2002
* '' P. simiae'' Vela et al. 2006
* '' P. sivasensis'' Duman et al. 2020
* '' P. spelaei'' Švec et al. 2020
* '' P. synxantha'' (Ehrenberg 1840) Holland 1920 (Approved Lists 1980)
* '' P. tolaasii'' Paine 1919 (Approved Lists 1980)
* '' P. tritici'' Girard et al. 2022
* '' P. trivialis'' Behrendt et al. 2003
* '' P. veronii'' Elomari et al. 1996
* '' P. yamanorum'' Arnau et al. 2015
''P. fragi'' Subgroup
* '' P. bubulae'' Lick et al. 2020
* '' P. deceptionensis'' Carrión et al. 2011
* '' P. endophytica'' Ramírez-Bahena et al. 2015
* '' P. fragi'' (Eichholz 1902) Gruber 1905 (Approved Lists 1980)
* '' P. helleri'' von Neubeck et al. 2016
* '' P. lundensis'' Molin et al. 1986
* '' P. paraversuta'' Lick et al. 2021
* '' P. psychrophila'' Yumoto et al. 2002
* '' P. saxonica'' Hofmann et al. 2020
* '' P. taetrolens'' Haynes 1957 (Approved Lists 1980)
* '' P. versuta'' See-Too et al. 2017
* '' P. weihenstephanensis'' von Neubeck et al. 2016
''P. gessardii'' Subgroup
* '' P. brenneri'' Baïda et al. 2002
* '' P. gessardii'' Verhille et al. 1999
* '' P. meridiana'' Reddy et al. 2004
* '' P. mucidolens'' Levine and Anderson 1932 (Approved Lists 1980)
* '' P. proteolytica'' Reddy et al. 2004
* '' P. shahriarae'' Girard et al. 2022
''P. jessenii'' Subgroup
* '' P. azerbaijanoccidentalis'' corrig. Girard et al. 2022
* '' P. azerbaijanorientalis'' corrig. Girard et al. 2022
* '' P. izuensis'' Lu et al. 2020
* '' P. jessenii'' Verhille et al. 1999
* '' P. laurylsulfatiphila'' corrig. Furmanczyk et al. 2019
* '' P. laurylsulfativorans'' corrig. Furmanczyk et al. 2019
* '' P. mohnii'' Cámara et al. 2007
* '' P. moorei'' Cámara et al. 2007
* '' P. reinekei'' Cámara et al. 2007
* '' P. umsongensis'' Kwon et al. 2003
* '' P. vancouverensis'' Mohn et al. 1999
''P. koreensis'' Subgroup
* '' P. allokribbensis'' Morimoto et al. 2021
* '' P. anatoliensis'' Duman et al. 2021
* '' P. atacamensis'' Poblete-Morales et al. 2021
* '' P. atagonensis'' corrig. Morimoto et al. 2020
* '' P. baetica'' López et al. 2012
* "'' P. bananamidigenes''" Girard et al. 2021
* "'' P. botevensis''" Girard et al. 2021
* "'' P. crudilactis''" Schlusselhuber et al. 2021
* '' P. ekonensis'' Girard et al. 2022
* '' P. glycinae'' Jia et al. 2021
* '' P. gozinkensis'' Morimoto et al. 2021
* '' P. granadensis'' Pascual et al. 2015
* '' P. hamedanensis'' Girard et al. 2022
* '' P. helmanticensis'' Ramírez-Bahena et al. 2014
* '' P. iranensis'' Girard et al. 2022
* '' P. iridis'' Duman et al. 2021
* '' P. khorasanensis'' Girard et al. 2022
* '' P. koreensis'' Kwon et al. 2003
* "'' P. kribbensis''" Chang et al. 2016
* '' P. monsensis'' Girard et al. 2022
* '' P. moraviensis'' Tvrzová et al. 2006
* '' P. neuropathica'' Duman et al. 2021
* '' P. siliginis'' Girard et al. 2022
* '' P. tensinigenes'' Girard et al. 2022
* '' P. triticicola'' Girard et al. 2022
* '' P. zeae'' Girard et al. 2022
''P. mandelii'' Subgroup
* '' P. arsenicoxydans'' Campos et al. 2011
* '' P. farris'' Girard et al. 2022
* '' P. frederiksbergensis'' Andersen et al. 2000
* "'' P. gregormendelii''" Kosina et al. 2016
* '' P. lini'' Delorme et al. 2002
* '' P. mandelii'' Verhille et al. 1999
* '' P. migulae'' Verhille et al. 1999
* '' P. mucoides'' Duman et al. 2021
* '' P. piscicola'' Duman et al. 2021
* '' P. prosekii'' Kosina et al. 2014
* '' P. silesiensis'' Kaminski et al. 2018
''P. protegens'' Subgroup
* "'' P. aestus''" Vasconcellos et al. 2017
* '' P. piscis'' Liu et al. 2020
* '' P. protegens'' Ramette et al. 2012
* '' P. saponiphila'' Lang et al. 2012
* "'' P. sessilinigenes''" Girard et al. 2021
''incertae sedis''
* "'' P. blatchfordae''" Blatchford and Schuster 1980
* '' P. kielensis'' Gieschler et al. 2021
''P. linyingensis'' Group
* '' P. guangdongensis'' Yang et al. 2013
* '' P. linyingensis'' He et al. 2015
* "'' P. oryzae''" Yu et al. 2013
* '' P. sagittaria'' Lin et al. 2013
''P. lutea'' Group
* '' P. abietaniphila'' Mohn et al. 1999
* '' P. bohemica'' Saati-Santamaría et al. 2018
* '' P. graminis'' Behrendt et al. 1999
* '' P. lutea'' Peix et al. 2004
''P. massiliensis'' Group
* "'' P. massiliensis''" Bardet et al. 2018
* '' P. typographi'' Peral-Aranega et al. 2021
''P. oleovorans'' Group
* '' P. alcaliphila'' Yumoto et al. 2001
* "'' P. chaetocerotis''" Girard et al.
* '' P. chengduensis'' Tao et al. 2014
* '' P. composti'' Gibello et al. 2011
* '' P. guguanensis'' Liu et al. 2013
* '' P. hydrolytica'' Zhou et al. 2020
* "'' P. indoloxydans''" Manickam et al. 2008
* '' P. khazarica'' Tarhriz et al. 2020
* '' P. mendocina'' Palleroni 1970 (Approved Lists 1980)
* '' P. oleovorans'' Lee and Chandler 1941 (Approved Lists 1980)
* "'' P. sediminis''" Behera et al. 2018
* "'' P. sihuiensis''" Wu et al. 2014
* '' P. toyotomiensis'' Hirota et al. 2011
''P. oryzihabitans'' Group
* '' P. asuensis'' Reddy and Garcia-Pichel 2015
* '' P. duriflava'' Liu et al. 2008
* '' P. luteola'' Kodama et al. 1985
* '' P. oryzihabitans'' Kodama et al. 1985
* '' P. rhizoryzae'' Wang et al. 2020
''P. pohangensis'' Group
* '' P. mangrovi'' Ye et al. 2019
* '' P. pohangensis'' Weon et al. 2006
''P. putida'' Group
* '' P. akappageensis'' corrig. Morimoto et al. 2020
* '' P. alkylphenolica'' Mulet et al. 2015
* '' P. alloputida'' Keshavarz-Tohid et al. 2020
* '' P. anuradhapurensis'' Girard et al. 2022
* '' P. arcuscaelestis'' Mulet et al. 2021
* '' P. asiatica'' Tohya et al. 2019
* '' P. brassicae'' Sawada et al. 2020
* "'' P. capeferrum''" Berendsen et al. 2015
* '' P. cremoricolorata'' Uchino et al. 2002
* '' P. defluvii'' Qin et al. 2020
* '' P. donghuensis'' Gao et al. 2015
* '' P. entomophila'' Mulet et al. 2012
* '' P. fakonensis'' Girard et al. 2022
* '' P. farsensis'' Girard et al. 2022
* '' P. fulva'' Iizuka and Komagata 1963 (Approved Lists 1980)
* '' P. guariconensis'' Toro et al. 2013
* '' P. huaxiensis'' Qin et al. 2019
* "'' P. hunanensis''" Gao et al. 2014
* "'' P. hutmensis''" Xiang et al. 2019
* '' P. inefficax'' Keshavarz-Tohid et al. 2019
* '' P. japonica'' Pungrasmi et al. 2008
* '' P. juntendi'' Tohya et al. 2019
* '' P. kermanshahensis'' Girard et al. 2022
* '' P. kurunegalensis'' Girard et al. 2022
* '' P. laurentiana'' Wright et al. 2019
* '' P. maumuensis'' Girard et al. 2022
* '' P. monteilii'' Elomari et al. 1997
* '' P. mosselii'' Dabboussi et al. 2002
* '' P. muyukensis'' Girard et al. 2022
* '' P. oryzicola'' Girard et al. 2022
* "'' P. oryziphila''" Yang et al. 2021
* '' P. palmensis'' Gutierrez-Albanchez et al. 2022
* '' P. parafulva'' Uchino et al. 2002
* '' P. peradeniyensis'' Girard et al. 2022
* '' P. persica'' Keshavarz-Tohid et al. 2020
* '' P. plecoglossicida'' Nishimori et al. 2000
* '' P. promysalinigenes'' Girard et al. 2022
* '' P. putida'' (Trevisan 1889) Migula 1895 (Approved Lists 1980)
* "'' P. pyomelaminifaciens''" Chakraborty et al.
* "'' P. qingdaonensis''" Wang et al. 2019
* '' P. reidholzensis'' Frasson et al. 2017
* '' P. shirazensis'' Girard et al. 2022
* '' P. shirazica'' Keshavarz-Tohid et al. 2020
* '' P. sichuanensis'' Qin et al. 2019
* '' P. soli'' Pascual et al. 2015
* '' P. taiwanensis'' Wang et al. 2010
* '' P. tructae'' Oh et al. 2019
* '' P. urmiensis'' Girard et al. 2022
* "'' P. vlassakiae''" Girard et al. 2021
* '' P. vranovensis'' Tvrzová et al. 2006
* '' P. wadenswilerensis'' Frasson et al. 2017
* "'' P. wayambapalatensis''" Girard et al. 2021
* '' P. xantholysinigenes'' Girard et al. 2022
* '' P. xanthosomatis'' corrig. Girard et al. 2022
''P. resinovorans'' Group
* '' P. furukawaii'' Kimura et al. 2018
* '' P. lalkuanensis'' Thorat et al. 2020
* '' P. mangiferae'' Anurat et al. 2019
* '' P. otitidis'' Clark et al. 2006
* '' P. resinovorans'' Delaporte et al. 1961 (Approved Lists 1980)
''P. rhizosphaerae'' Group
* '' P. baltica'' Gieschler et al. 2021
* '' P. coleopterorum'' Menéndez et al. 2015
* "'' P. eucalypticola''" Liu et al. 2021
* '' P. rhizosphaerae'' Peix et al. 2003
''P. straminea'' Group
* '' P. argentinensis'' Peix et al. 2005
* '' P. daroniae'' Bueno-Gonzalez et al. 2019
* '' P. dryadis'' Bueno-Gonzalez et al. 2019
* '' P. flavescens'' Hildebrand et al. 1994
* '' P. punonensis'' Ramos et al. 2013
* '' P. seleniipraecipitans'' corrig. Hunter and Manter 2011
* '' P. straminea'' corrig. Iizuka and Komagata 1963 (Approved Lists 1980)
''P. stutzeri'' Group
* '' P. azotifigens'' Hatayama et al. 2005
* '' P. balearica'' Bennasar et al. 1996
* '' P. chloritidismutans'' Wolterink et al. 2002
* '' P. kirkiae'' Bueno-Gonzalez et al. 2020
* '' P. nitrititolerans'' Peng et al. 2019
* '' P. nosocomialis'' Mulet et al. 2019
* "'' P. saudiphocaensis''" Azhar et al. 2017
* "'' P. songnenensis''" Zhang et al. 2015
* '' P. stutzeri'' (Lehmann and Neumann 1896) Sijderius 1946 (Approved Lists 1980)
* '' P. urumqiensis'' Zou et al. 2019
* '' P. xanthomarina'' Romanenko et al. 2005
* '' P. zhaodongensis'' Zhang et al. 2015
''P. syringae'' Group
* "'' P. alliivorans''" Zhao et al. 2021
* '' P. amygdali'' Psallidas and Panagopoulos 1975 (Approved Lists 1980)
* '' P. asturiensis'' González et al. 2013
* '' P. avellanae'' Janse et al. 1997
* '' P. cannabina'' (ex Šutič and Dowson 1959) Gardan et al. 1999
* '' P. capsici'' Zhao et al. 2021
* '' P. caricapapayae'' Robbs 1956 (Approved Lists 1980)
* '' P. caspiana'' Busquets et al. 2017
* '' P. cerasi'' Kałuzna et al. 2017
* '' P. cichorii'' (Swingle 1925) Stapp 1928 (Approved Lists 1980)
* '' P. congelans'' Behrendt et al. 2003
* "'' P. coronafaciens''" (Elliott 1920) Stevens 1958
* '' P. ficuserectae'' Goto 1983
* '' P. floridensis'' Timilsina et al. 2018
* "'' P. foliumensis''" Tambong et al. 2021
* "'' P. helianthi''" Elasri et al. 2001
* '' P. meliae'' Ogimi 1981
* '' P. ovata'' Rao et al. 2021
* '' P. savastanoi'' (Janse 1982) Gardan et al. 1992
* '' P. syringae'' van Hall 1902 (Approved Lists 1980)
* "'' P. tomato''" Gardan et al. 1999
* '' P. tremae'' Gardan et al. 1999
* "'' P. triticumensis''" Tambong et al. 2021
* '' P. viridiflava'' (Burkholder 1930) Dowson 1939 (Approved Lists 1980)
''
incertae sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...
''
* "'' P. acephalitica''" Tapia-Paniagua et al. 2014
* "'' P. acidophila''" Imada et al. 1981
* " ''Ca.'' P. adelgestsugas" von Dohlen et al. 2013
* '' P. alcaligenes'' Monias 1928 (Approved Lists 1980)
* "'' P. alginovora''" Boyen et al. 1990
* "'' P. alkanolytica''" Nakao and Kuno 1972
* "'' P. amyloderamosa''" Norrman and Wober 1975
* "'' P. andersonii''" Han et al. 2001
* "'' P. bathycetes''" Quigley and Colwell 1968
* "'' P. borealis''" Wilson et al. 2006
* '' P. cavernae'' Zhu et al. 2022
* '' P. cavernicola'' Zhu et al. 2022
* "'' P. cellulosa''" Andrews et al. 2000
* "'' P. clemancea''" Rahman et al. 2010
* "'' P. coenobios''" ZoBell and Upham 1944
* "'' P. diazotrophicus''" Watanabe et al. 1987
* "'' P. diterpeniphila''" Morgan and Wyndham 2002
* "'' P. elodea''" Fialho et al. 1991
* "'' P. excibis''" Steinhaus
* '' P. flexibilis'' (Hespell 1977) Shin et al. 2016
* '' P. fluvialis'' Sudan et al. 2018
* '' P. gelidicola'' Kadota 1951 (Approved Lists 1980)
* "'' P. guezennei''" Simon-Colin et al. 2008
* "'' P. halodenitrificans''" Alonso et al. 2001
* "'' P. halodurans''" Cuhel et al. 1981
* "'' P. halosaccharolytica''" Ohno et al. 1976
* "'' P. halosensibilis''" Zou and Cai 1994
* "'' P. hydrogenothermophila''" Goto et al. 1978
* "'' P. hydrogenovora''" Igarashi et al. 1980
* '' P. indica'' Pandey et al. 2002
* "'' P. jinanensis''" Cai et al. 1989
* '' P. kuykendallii'' Hunter and Manter 2012
* "'' P. lopnurensis''" Mamtimin et al. 2021
* "'' P. lubricans''" Rehman et al. 2010
* '' P. matsuisoli'' Lin et al. 2015
* "'' P. melophthora'' Allen and Riker 1932
* "'' P. mesoacidophila''" Kintaka et al. 1981
* "'' P. multiresinovorans''" Hernandez et al. 2008
* "'' P. perolens''" Szybalski 1950
* '' P. pharmacofabricae'' corrig. Yu et al. 2019
* "'' P. pratensis''" Zhang et al. 2021
* '' P. quercus'' Li et al. 2021
* "'' P. raguenesii''" Simon-Colin et al. 2009
* "'' P. reactans''" Preece and Wong 1982
* "'' P. reptilivora''" Caldwell and Ryerson 1940
* "'' P. rhizophila''" Hassen et al. 2018
* "'' P. rhizovicinus''" He et al. 2021
* "'' P. rubescens''" Pivnick 1955
* '' P. schmalbachii'' Shelomi et al. 2021
* "'' P. septica''" Bergey et al. 1930
* '' P. sesami'' Madhaiyan et al. 2017
* "'' P. siderocapsa''" Falamin and Pinevich 2006
* "'' P. suis''" Woods 1930
* "'' P. tamsuii''" Liang et al. 2015
* '' P. tarimensis'' Anwar et al. 2017
* "'' P. teessidea''" Rahman et al. 2010
* "'' P. thermocarboxydovorans''" Lyons et al. 1984
* '' P. thermotolerans'' Manaia and Moore 2002
* '' P. tianjinensis'' Chen et al. 2018
* '' P. tohonis'' Yamada et al. 2021
* "'' P. turbinellae''" Sreenivasan 1956
* '' P. turukhanskensis'' Korshunova et al. 2016
* "'' P. tuticorinensis''" Sreenivasan 1956
* "'' P. wenzhouensis''" Zhang et al. 2021
* '' P. xionganensis'' Zhao et al. 2020
* '' P. yangonensis'' Tohya et al. 2020
Species previously classified in the genus
Recently, 16S rRNA sequence analysis redefined the taxonomy of many bacterial species previously classified as being in the genus ''Pseudomonas''. Species removed from ''Pseudomonas'' are listed below; clicking on a species will show its new classification. The term 'pseudomonad' does not apply strictly to just the genus ''Pseudomonas'', and can be used to also include previous members such as the genera ''Burkholderia
''Burkholderia'' is a genus of Pseudomonadota whose pathogenic members include the ''Burkholderia cepacia'' complex, which attacks humans and ''Burkholderia mallei'', responsible for glanders, a disease that occurs mostly in horses and related ...
'' and ''Ralstonia
''Ralstonia'' is a genus of bacteria, previously included in the genus ''Pseudomonas''. It is named after the American bacteriologist Ericka Ralston. Ericka Ralston was born Ericka Barrett in 1944 in Saratoga, California, and died in 2015 in Seb ...
''.
α proteobacteria: '' P. abikonensis'', '' P. aminovorans'', '' P. azotocolligans'', '' P. carboxydohydrogena'', '' P. carboxidovorans'', '' P. compransoris'', '' P. diminuta'', '' P. echinoides'', '' P. extorquens'', '' P. lindneri'', '' P. mesophilica'', '' P. paucimobilis'', '' P. radiora'', '' P. rhodos'', '' P. riboflavina'', '' P. rosea'', '' P. vesicularis''.
β proteobacteria: '' P. acidovorans'', '' P. alliicola'', '' P. antimicrobica'', '' P. avenae'', '' P. butanovora'', '' P. caryophylli'', '' P. cattleyae'', '' P. cepacia'', '' P. cocovenenans'', '' P. delafieldii'', '' P. facilis'', '' P. flava'', '' P. gladioli'', '' P. glathei'', '' P. glumae'', '' P. huttiensis'', '' P. indigofera'', '' P. lanceolata'', '' P. lemoignei'', '' B. mallei'', '' P. mephitica'', '' P. mixta'', '' P. palleronii'', '' P. phenazinium'', '' P. pickettii'', '' P. plantarii'', '' P. pseudoflava'', '' B. pseudomallei'', '' P. pyrrocinia'', '' P. rubrilineans'', '' P. rubrisubalbicans'', '' P. saccharophila'', '' P. solanacearum'', '' P. spinosa'', '' P. syzygii'', '' P. taeniospiralis'', '' P. terrigena'', '' P. testosteroni''.
γ-β proteobacteria: '' P. boreopolis'', '' P. cissicola'', '' P. geniculata'', '' P. hibiscicola'', '' P. maltophilia'', '' P. pictorum''.
γ proteobacteria: '' P. beijerinckii'', '' P. diminuta'', '' P. doudoroffii'', '' P. elongata'', '' P. flectens'', '' P. marinus'', '' P. halophila'', '' P. iners'', '' P. marina'', '' P. nautica'', '' P. nigrifaciens'', '' P. pavonacea'', '' P. piscicida'', '' P. stanieri''.
δ proteobacteria: '' P. formicans''.
Phylogenetics
The following relationships between genomic affinity groups have been determined by phylogenetic analysis
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
:
Bacteriophages
There are a number of bacteriophage
A bacteriophage (), also known informally as a ''phage'' (), is a duplodnaviria virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν ('), meaning "to devour". Bacteri ...
s that infect ''Pseudomonas'', e.g.
* ''Pseudomonas'' phage Φ6
* ''Pseudomonas'' phage ΦCTX
* ''Pseudomonas aeruginosa'' phage EL
* ''Pseudomonas aeruginosa'' phage ΦKMV (a Phikmvvirus
''Phikmvvirus'' is a genus of viruses that infect bacteria. There are currently 16 species in this genus including the type species '' Pseudomonas virus phiKMV''.
Bacteriophage phiKMV and its relatives are known to be highly virulent phages, pr ...
)
* ''Pseudomonas aeruginosa'' phage LKD16 (a Phikmvvirus
''Phikmvvirus'' is a genus of viruses that infect bacteria. There are currently 16 species in this genus including the type species '' Pseudomonas virus phiKMV''.
Bacteriophage phiKMV and its relatives are known to be highly virulent phages, pr ...
)
* ''Pseudomonas aeruginosa'' phage LKA1 (a Phikmvvirus
''Phikmvvirus'' is a genus of viruses that infect bacteria. There are currently 16 species in this genus including the type species '' Pseudomonas virus phiKMV''.
Bacteriophage phiKMV and its relatives are known to be highly virulent phages, pr ...
)
* ''Pseudomonas aeruginosa'' phage LUZ19 (a Phikmvvirus
''Phikmvvirus'' is a genus of viruses that infect bacteria. There are currently 16 species in this genus including the type species '' Pseudomonas virus phiKMV''.
Bacteriophage phiKMV and its relatives are known to be highly virulent phages, pr ...
)
* ''Pseudomonas aeruginosa'' phage ΦKZ
* ''Pseudomonas putida'' phage gh-1
See also
* Culture collection
A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture medium under controlled laboratory conditions. Microbial cultures are foundational and basic diagn ...
for a list of culture collections
Footnotes
References
External links
General
Pseudomonas at origin of world's rain and snow
''Pseudomonas'' genome database
* Fluorescent Pseudomona
{{portal bar, Biology
Pseudomonadales
Bacteria genera
Psychrophiles
Gram-negative bacteria
Pathogenic bacteria