Classification history
Like most bacterial genera, the pseudomonad last common ancestor lived hundreds of millions of years ago. They were initially classified at the end of the 19th century when first identified by Walter Migula. 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 Ancient Greek, Greek ''pseudes ''(ψευδής) "false" and ''-monas'' (μονάς/μονάδος) "a single unit", which can mean false unit; however, Migula possibly intended it as false ''Monas (genus), Monas'', 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. However, many strains have since been reclassified, based on more recent methodology and use of approaches involving studies of conservative macromolecules. Recently, 16S ribosomal RNA, 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'' and ''Ralstonia''. 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 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. ''Characteristics
Members of the genus display these defining characteristics: * Bacillus (shape), Rod-shaped * Gram-negative * Flagellum one or more, providing motility * aerobic organism, Aerobic * Bacterial spore, Non-spore forming * Catalase#Catalase test, Catalase-positive * Oxidase test#Classification, Oxidase-positive Other characteristics that tend to be associated with ''Pseudomonas'' species (with some exceptions) include secretion of pyoverdine, a Fluorescence, fluorescent yellow-green siderophore under iron-limiting conditions. Certain ''Pseudomonas'' species may also produce additional types of siderophore, such as pyocyanin by '' Pseudomonas aeruginosa'' and thioquinolobactin by ''Pseudomonas fluorescens'',. ''Pseudomonas'' species also typically give a positive result to the oxidase test, the absence of gas formation from glucose, glucose is oxidised in oxidation/fermentation test using Hugh and Leifson O/F test, beta hemolytic (on blood agar), indole test, indole negative, methyl red negative, Voges–Proskauer test negative, and citrate test, citrate 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 and strains of ''Pseudomonas'' have historically been classified as Aerobic organism, strict aerobes. Exceptions to this classification have recently been discovered in ''Pseudomonas'' biofilms. A significant number of cells can produce exopolysaccharides associated with biofilm formation. Secretion of exopolysaccharides such as alginate makes it difficult for pseudomonads to be phagocytosed by mammalian white blood cells. Exopolysaccharide production also contributes to surface-colonising biofilms 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 and the majority of related beta-lactam antibiotics, but a number are sensitive to piperacillin, imipenem, ticarcillin, or ciprofloxacin. Aminoglycosides such as tobramycin, gentamicin, and amikacin are other choices for therapy. This ability to thrive in harsh conditions is a result of their hardy cell walls that contain Porin (protein), porins. Their resistance to most antibiotics is attributed to Efflux (microbiology), efflux pumps, which pump out some antibiotics before they are able to act. '' Pseudomonas aeruginosa'' is increasingly recognized as an emerging opportunistic pathogen 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 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 chromosomally encoded genes or by the horizontal gene transfer of antibiotic resistance determinants. Development of multidrug resistance 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 integrons favours the concerted acquisition of antibiotic resistance determinants. Some recent studies have shown phenotypic resistance associated to biofilm formation or to the emergence of small-colony-variants, which may be important in the response of ''P. aeruginosa'' populations to antibiotic treatment.Sensitivity to Gallium
Although gallium 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 ''Plant Pathogens
''P. syringae'' is a prolific plant pathogen. It exists as over 50 different pathovars, 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, ''Pseudomonas tolaasii, P. tolaasii'' can be a major agricultural problem, as it can cause bacterial blotch of cultivated mushrooms. Similarly, ''Pseudomonas agarici, 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. The biocontrol properties of ''P. fluorescens'' and ''Pseudomonas protegens, 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 siderophores giving a competitive advantage at scavenging for iron; the bacteria might produce compounds antagonistic to other soil microbes, such as phenazine-type antibiotics or hydrogen cyanide. Experimental evidence supports all of these theories. Other notable ''Pseudomonas'' species with biocontrol properties include ''Pseudomonas chlororaphis, P. chlororaphis'', which produces a phenazine-type antibiotic active agent against certain fungus, fungal plant pathogens, and the closely related species ''Pseudomonas aurantiaca, P. aurantiaca'', which produces di-2,4-diacetylfluoroglucylmethane, a compound antibiotically active against Gram-positive 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. Notable species demonstrated as suitable for use as bioremediation agents include: * ''Pseudomonas alcaligenes, P. alcaligenes'', which can degrade polycyclic aromatic hydrocarbons. * ''Pseudomonas mendocina, P. mendocina'', which is able to degrade toluene. * ''Pseudomonas pseudoalcaligenes, P. pseudoalcaligenes'', which is able to use cyanide as a nitrogen source. * ''Pseudomonas resinovorans, P. resinovorans'', which can degrade carbazole. *''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, polymerase chain reaction (PCR). 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 ''Pseudomonas flourescens, P. fluorescens'', 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 ''Pseudomonas flourescens, P. fluorescens'' and ''Pseudomonas aureofaciens, P. aureofaciens''.Species
''Pseudomonas'' comprises the following species, organized into genomic affinity groups:''P. aeruginosa'' Group
* ''''P. anguilliseptica'' Group
* ''Pseudomonas anguilliseptica, P. anguilliseptica'' Wakabayashi and Egusa 1972 (Approved Lists 1980) * ''Pseudomonas benzenivorans, P. benzenivorans'' Lang et al. 2012 * ''Pseudomonas borbori, P. borbori'' Vanparys et al. 2006 * ''Pseudomonas campi, P. campi'' Timsy et al. 2021 * ''Pseudomonas cuatrocienegasensis, P. cuatrocienegasensis'' Escalante et al. 2009 * ''Pseudomonas glareae, P. glareae'' Romanenko et al. 2015 * ''Pseudomonas guineae, P. guineae'' Bozal et al. 2007 * ''Pseudomonas guryensis, P. guryensis'' Kim et al. 2021 * ''Pseudomonas lalucatii, P. lalucatii'' Busquets et al. 2021 * ''Pseudomonas leptonychotis, P. leptonychotis'' Nováková et al. 2020 * ''Pseudomonas marincola, P. marincola'' Romanenko et al. 2008 * ''Pseudomonas peli, P. peli'' Vanparys et al. 2006 * ''Pseudomonas segitis, P. segitis'' Park et al. 2006 * ''Pseudomonas taeanensis, P. taeanensis'' Lee et al. 2010 * ''Pseudomonas ullengensis, P. ullengensis'' Kim et al. 2021''P. fluorescens'' Group
''P. asplenii'' Subgroup * ''Pseudomonas agarici, P. agarici'' Young 1970 (Approved Lists 1980) * ''Pseudomonas asplenii, P. asplenii'' (Ark and Tompkins 1946) Savulescu 1947 (Approved Lists 1980) * "''Pseudomonas batumici, P. batumici''" Kiprianova et al. 2011 * ''Pseudomonas fuscovaginae, P. fuscovaginae'' (ex Tanii et al. 1976) Miyajima et al. 1983 * "''Pseudomonas gingeri, P. gingeri''" Cutri et al. 1984 * ''Pseudomonas vanderleydeniana, P. vanderleydeniana'' Girard et al. 2022 ''P. chlororaphis'' Subgroup * ''Pseudomonas aurantiaca, P. aurantiaca'' Nakhimovskaya 1948 (Approved Lists 1980) * ''Pseudomonas aureofaciens, P. aureofaciens'' Kluyver 1956 (Approved Lists 1980) * ''Pseudomonas chlororaphis, P. chlororaphis'' (Guignard and Sauvageau 1894) Bergey et al. 1930 (Approved Lists 1980) * "''Pseudomonas piscium, P. piscium''" (Burr et al. 2010) Chen et al. 2018 ''P. corrugata'' Subgroup * ''Pseudomonas alvandae, P. alvandae'' Girard et al. 2022 * ''Pseudomonas bijieensis, P. bijieensis'' Liang et al. 2021 * ''Pseudomonas brassicacearum, P. brassicacearum'' Achouak et al. 2000 * ''Pseudomonas canavaninivorans, P. canavaninivorans'' Hauth et al. 2022 * ''Pseudomonas corrugata, P. corrugata'' Roberts and Scarlett 1981 * ''Pseudomonas kilonensis, P. kilonensis'' Sikorski et al. 2001 * ''Pseudomonas marvdashtae, P. marvdashtae'' Girard et al. 2022 * ''Pseudomonas mediterranea, P. mediterranea'' Catara et al. 2002 * ''Pseudomonas ogarae, P. ogarae'' Garrido-Sanz et al. 2022 * ''Pseudomonas tehranensis, P. tehranensis'' Girard et al. 2022 * ''Pseudomonas thivervalensis, P. thivervalensis'' Achouak et al. 2000 * ''Pseudomonas viciae, P. viciae'' Zhao et al. 2020 * ''Pseudomonas zanjanensis, P. zanjanensis'' Girard et al. 2022 * ''Pseudomonas zarinae, P. zarinae'' Girard et al. 2022 ''P. fluorescens'' Subgroup * ''Pseudomonas allii, P. allii'' Sawada et al. 2021 * ''Pseudomonas antarctica, P. antarctica'' Reddy et al. 2004 * ''Pseudomonas asgharzadehiana, P. asgharzadehiana'' Girard et al. 2022 * ''Pseudomonas aylmerensis, P. aylmerensis'' corrig. Tchagang et al. 2021 * ''Pseudomonas azadiae, P. azadiae'' Girard et al. 2022 * ''Pseudomonas azotoformans, P. azotoformans'' Iizuka and Komagata 1963 (Approved Lists 1980) * ''Pseudomonas canadensis, P. canadensis'' Tambong et al. 2017 * ''Pseudomonas carnis, P. carnis'' Lick et al. 2020 * ''Pseudomonas cedrina, P. cedrina'' corrig. Dabboussi et al. 2002 * ''Pseudomonas costantinii, P. costantinii'' Munsch et al. 2002 * ''Pseudomonas cremoris, P. cremoris'' Hofmann et al. 2021 * ''Pseudomonas cyclaminis, P. cyclaminis'' Sawada et al. 2021 * ''Pseudomonas edaphica, P. edaphica'' Ramírez-Bahena et al. 2019 * ''Pseudomonas extremaustralis, P. extremaustralis'' López et al. 2010 * ''Pseudomonas extremorientalis, P. extremorientalis'' Ivanova et al. 2002 * ''Pseudomonas fildesensis, P. fildesensis'' Pavlov et al. 2020 * ''''P. linyingensis'' Group
* ''Pseudomonas guangdongensis, P. guangdongensis'' Yang et al. 2013 * ''Pseudomonas linyingensis, P. linyingensis'' He et al. 2015 * "''Pseudomonas oryzae, P. oryzae''" Yu et al. 2013 * ''Pseudomonas sagittaria, P. sagittaria'' Lin et al. 2013''P. lutea'' Group
* ''Pseudomonas abietaniphila, P. abietaniphila'' Mohn et al. 1999 * ''Pseudomonas bohemica, P. bohemica'' Saati-Santamaría et al. 2018 * ''Pseudomonas graminis, P. graminis'' Behrendt et al. 1999 * ''Pseudomonas lutea, P. lutea'' Peix et al. 2004''P. massiliensis'' Group
* "''Pseudomonas massiliensis, P. massiliensis''" Bardet et al. 2018 * ''Pseudomonas typographi, P. typographi'' Peral-Aranega et al. 2021''P. oleovorans'' Group
* ''Pseudomonas alcaliphila, P. alcaliphila'' Yumoto et al. 2001 * "''Pseudomonas chaetocerotis, P. chaetocerotis''" Girard et al. * ''Pseudomonas chengduensis, P. chengduensis'' Tao et al. 2014 * ''Pseudomonas composti, P. composti'' Gibello et al. 2011 * ''Pseudomonas guguanensis, P. guguanensis'' Liu et al. 2013 * ''Pseudomonas hydrolytica, P. hydrolytica'' Zhou et al. 2020 * "''Pseudomonas indoloxydans, P. indoloxydans''" Manickam et al. 2008 * ''Pseudomonas khazarica, P. khazarica'' Tarhriz et al. 2020 * ''Pseudomonas mendocina, P. mendocina'' Palleroni 1970 (Approved Lists 1980) * ''Pseudomonas oleovorans, P. oleovorans'' Lee and Chandler 1941 (Approved Lists 1980) * "''Pseudomonas sediminis, P. sediminis''" Behera et al. 2018 * "''Pseudomonas sihuiensis, P. sihuiensis''" Wu et al. 2014 * ''Pseudomonas toyotomiensis, P. toyotomiensis'' Hirota et al. 2011''P. oryzihabitans'' Group
* ''Pseudomonas asuensis, P. asuensis'' Reddy and Garcia-Pichel 2015 * ''Pseudomonas duriflava, P. duriflava'' Liu et al. 2008 * ''Pseudomonas luteola, P. luteola'' Kodama et al. 1985 * ''Pseudomonas oryzihabitans, P. oryzihabitans'' Kodama et al. 1985 * ''Pseudomonas rhizoryzae, P. rhizoryzae'' Wang et al. 2020''P. pohangensis'' Group
* ''Pseudomonas mangrovi, P. mangrovi'' Ye et al. 2019 * ''Pseudomonas pohangensis, P. pohangensis'' Weon et al. 2006''P. putida'' Group
* ''Pseudomonas akappageensis, P. akappageensis'' corrig. Morimoto et al. 2020 * ''Pseudomonas alkylphenolica, P. alkylphenolica'' Mulet et al. 2015 * ''Pseudomonas alloputida, P. alloputida'' Keshavarz-Tohid et al. 2020 * ''Pseudomonas anuradhapurensis, P. anuradhapurensis'' Girard et al. 2022 * ''Pseudomonas arcuscaelestis, P. arcuscaelestis'' Mulet et al. 2021 * ''Pseudomonas asiatica, P. asiatica'' Tohya et al. 2019 * ''Pseudomonas brassicae, P. brassicae'' Sawada et al. 2020 * "''Pseudomonas capeferrum, P. capeferrum''" Berendsen et al. 2015 * ''Pseudomonas cremoricolorata, P. cremoricolorata'' Uchino et al. 2002 * ''Pseudomonas defluvii, P. defluvii'' Qin et al. 2020 * ''Pseudomonas donghuensis, P. donghuensis'' Gao et al. 2015 * ''Pseudomonas entomophila, P. entomophila'' Mulet et al. 2012 * ''Pseudomonas fakonensis, P. fakonensis'' Girard et al. 2022 * ''Pseudomonas farsensis, P. farsensis'' Girard et al. 2022 * ''Pseudomonas fulva, P. fulva'' Iizuka and Komagata 1963 (Approved Lists 1980) * ''Pseudomonas guariconensis, P. guariconensis'' Toro et al. 2013 * ''Pseudomonas huaxiensis, P. huaxiensis'' Qin et al. 2019 * "''Pseudomonas hunanensis, P. hunanensis''" Gao et al. 2014 * "''Pseudomonas hutmensis, P. hutmensis''" Xiang et al. 2019 * ''Pseudomonas inefficax, P. inefficax'' Keshavarz-Tohid et al. 2019 * ''Pseudomonas japonica, P. japonica'' Pungrasmi et al. 2008 * ''Pseudomonas juntendi, P. juntendi'' Tohya et al. 2019 * ''Pseudomonas kermanshahensis, P. kermanshahensis'' Girard et al. 2022 * ''Pseudomonas kurunegalensis, P. kurunegalensis'' Girard et al. 2022 * ''Pseudomonas laurentiana, P. laurentiana'' Wright et al. 2019 * ''Pseudomonas maumuensis, P. maumuensis'' Girard et al. 2022 * ''Pseudomonas monteilii, P. monteilii'' Elomari et al. 1997 * ''Pseudomonas mosselii, P. mosselii'' Dabboussi et al. 2002 * ''Pseudomonas muyukensis, P. muyukensis'' Girard et al. 2022 * ''Pseudomonas oryzicola, P. oryzicola'' Girard et al. 2022 * "''Pseudomonas oryziphila, P. oryziphila''" Yang et al. 2021 * ''Pseudomonas palmensis, P. palmensis'' Gutierrez-Albanchez et al. 2022 * ''Pseudomonas parafulva, P. parafulva'' Uchino et al. 2002 * ''Pseudomonas peradeniyensis, P. peradeniyensis'' Girard et al. 2022 * ''Pseudomonas persica, P. persica'' Keshavarz-Tohid et al. 2020 * ''Pseudomonas plecoglossicida, P. plecoglossicida'' Nishimori et al. 2000 * ''Pseudomonas promysalinigenes, P. promysalinigenes'' Girard et al. 2022 * '' P. putida'' (Trevisan 1889) Migula 1895 (Approved Lists 1980) * "''Pseudomonas pyomelaminifaciens, P. pyomelaminifaciens''" Chakraborty et al. * "''Pseudomonas qingdaonensis, P. qingdaonensis''" Wang et al. 2019 * ''Pseudomonas reidholzensis, P. reidholzensis'' Frasson et al. 2017 * ''Pseudomonas shirazensis, P. shirazensis'' Girard et al. 2022 * ''Pseudomonas shirazica, P. shirazica'' Keshavarz-Tohid et al. 2020 * ''Pseudomonas sichuanensis, P. sichuanensis'' Qin et al. 2019 * ''Pseudomonas soli, P. soli'' Pascual et al. 2015 * ''Pseudomonas taiwanensis, P. taiwanensis'' Wang et al. 2010 * ''Pseudomonas tructae, P. tructae'' Oh et al. 2019 * ''Pseudomonas urmiensis, P. urmiensis'' Girard et al. 2022 * "''Pseudomonas vlassakiae, P. vlassakiae''" Girard et al. 2021 * ''Pseudomonas vranovensis, P. vranovensis'' Tvrzová et al. 2006 * ''Pseudomonas wadenswilerensis, P. wadenswilerensis'' Frasson et al. 2017 * "''Pseudomonas wayambapalatensis, P. wayambapalatensis''" Girard et al. 2021 * ''Pseudomonas xantholysinigenes, P. xantholysinigenes'' Girard et al. 2022 * ''Pseudomonas xanthosomatis, P. xanthosomatis'' corrig. Girard et al. 2022''P. resinovorans'' Group
* ''Pseudomonas furukawaii, P. furukawaii'' Kimura et al. 2018 * ''Pseudomonas lalkuanensis, P. lalkuanensis'' Thorat et al. 2020 * ''Pseudomonas mangiferae, P. mangiferae'' Anurat et al. 2019 * ''Pseudomonas otitidis, P. otitidis'' Clark et al. 2006 * ''Pseudomonas resinovorans, P. resinovorans'' Delaporte et al. 1961 (Approved Lists 1980)''P. rhizosphaerae'' Group
* ''Pseudomonas baltica, P. baltica'' Gieschler et al. 2021 * ''Pseudomonas coleopterorum, P. coleopterorum'' Menéndez et al. 2015 * "''Pseudomonas eucalypticola, P. eucalypticola''" Liu et al. 2021 * ''Pseudomonas rhizosphaerae, P. rhizosphaerae'' Peix et al. 2003''P. straminea'' Group
* ''Pseudomonas argentinensis, P. argentinensis'' Peix et al. 2005 * ''Pseudomonas daroniae, P. daroniae'' Bueno-Gonzalez et al. 2019 * ''Pseudomonas dryadis, P. dryadis'' Bueno-Gonzalez et al. 2019 * ''Pseudomonas flavescens, P. flavescens'' Hildebrand et al. 1994 * ''Pseudomonas punonensis, P. punonensis'' Ramos et al. 2013 * ''Pseudomonas seleniipraecipitans, P. seleniipraecipitans'' corrig. Hunter and Manter 2011 * ''Pseudomonas straminea, P. straminea'' corrig. Iizuka and Komagata 1963 (Approved Lists 1980)''P. stutzeri'' Group
* ''Pseudomonas azotifigens, P. azotifigens'' Hatayama et al. 2005 * ''Pseudomonas balearica, P. balearica'' Bennasar et al. 1996 * ''Pseudomonas chloritidismutans, P. chloritidismutans'' Wolterink et al. 2002 * ''Pseudomonas kirkiae, P. kirkiae'' Bueno-Gonzalez et al. 2020 * ''Pseudomonas nitrititolerans, P. nitrititolerans'' Peng et al. 2019 * ''Pseudomonas nosocomialis, P. nosocomialis'' Mulet et al. 2019 * "''Pseudomonas saudiphocaensis, P. saudiphocaensis''" Azhar et al. 2017 * "''Pseudomonas songnenensis, P. songnenensis''" Zhang et al. 2015 * ''Pseudomonas stutzeri, P. stutzeri'' (Lehmann and Neumann 1896) Sijderius 1946 (Approved Lists 1980) * ''Pseudomonas urumqiensis, P. urumqiensis'' Zou et al. 2019 * ''Pseudomonas xanthomarina, P. xanthomarina'' Romanenko et al. 2005 * ''Pseudomonas zhaodongensis, P. zhaodongensis'' Zhang et al. 2015''P. syringae'' Group
* "''Pseudomonas alliivorans, P. alliivorans''" Zhao et al. 2021 * ''Pseudomonas amygdali, P. amygdali'' Psallidas and Panagopoulos 1975 (Approved Lists 1980) * ''Pseudomonas asturiensis, P. asturiensis'' González et al. 2013 * ''Pseudomonas avellanae, P. avellanae'' Janse et al. 1997 * ''Pseudomonas cannabina, P. cannabina'' (ex Šutič and Dowson 1959) Gardan et al. 1999 * ''Pseudomonas capsici, P. capsici'' Zhao et al. 2021 * ''Pseudomonas caricapapayae, P. caricapapayae'' Robbs 1956 (Approved Lists 1980) * ''Pseudomonas caspiana, P. caspiana'' Busquets et al. 2017 * ''Pseudomonas cerasi, P. cerasi'' Kałuzna et al. 2017 * ''Pseudomonas cichorii, P. cichorii'' (Swingle 1925) Stapp 1928 (Approved Lists 1980) * ''Pseudomonas congelans, P. congelans'' Behrendt et al. 2003 * "''Pseudomonas coronafaciens, P. coronafaciens''" (Elliott 1920) Stevens 1958 * ''Pseudomonas ficuserectae, P. ficuserectae'' Goto 1983 * ''Pseudomonas floridensis, P. floridensis'' Timilsina et al. 2018 * "''Pseudomonas foliumensis, P. foliumensis''" Tambong et al. 2021 * "''Pseudomonas helianthi, P. helianthi''" Elasri et al. 2001 * ''Pseudomonas meliae, P. meliae'' Ogimi 1981 * ''Pseudomonas ovata, P. ovata'' Rao et al. 2021 * ''Pseudomonas savastanoi, P. savastanoi'' (Janse 1982) Gardan et al. 1992 * '' P. syringae'' van Hall 1902 (Approved Lists 1980) * "''Pseudomonas tomato, P. tomato''" Gardan et al. 1999 * ''Pseudomonas tremae, P. tremae'' Gardan et al. 1999 * "''Pseudomonas triticumensis, P. triticumensis''" Tambong et al. 2021 * ''Pseudomonas viridiflava, P. viridiflava'' (Burkholder 1930) Dowson 1939 (Approved Lists 1980)''incertae sedis''
* "''Pseudomonas acephalitica, P. acephalitica''" Tapia-Paniagua et al. 2014 * "''Pseudomonas acidophila, P. acidophila''" Imada et al. 1981 * "Pseudomonas adelgestsugas, ''Ca.'' P. adelgestsugas" von Dohlen et al. 2013 * ''Pseudomonas alcaligenes, P. alcaligenes'' Monias 1928 (Approved Lists 1980) * "''Pseudomonas alginovora, P. alginovora''" Boyen et al. 1990 * "''Pseudomonas alkanolytica, P. alkanolytica''" Nakao and Kuno 1972 * "''Pseudomonas amyloderamosa, P. amyloderamosa''" Norrman and Wober 1975 * "''Pseudomonas andersonii, P. andersonii''" Han et al. 2001 * "''Pseudomonas bathycetes, P. bathycetes''" Quigley and Colwell 1968 * "''Pseudomonas borealis, P. borealis''" Wilson et al. 2006 * ''Pseudomonas cavernae, P. cavernae'' Zhu et al. 2022 * ''Pseudomonas cavernicola, P. cavernicola'' Zhu et al. 2022 * "''Pseudomonas cellulosa, P. cellulosa''" Andrews et al. 2000 * "''Pseudomonas clemancea, P. clemancea''" Rahman et al. 2010 * "''Pseudomonas coenobios, P. coenobios''" ZoBell and Upham 1944 * "''Pseudomonas diazotrophicus, P. diazotrophicus''" Watanabe et al. 1987 * "''Pseudomonas diterpeniphila, P. diterpeniphila''" Morgan and Wyndham 2002 * "''Pseudomonas elodea, P. elodea''" Fialho et al. 1991 * "''Pseudomonas excibis, P. excibis''" Steinhaus * ''Pseudomonas flexibilis, P. flexibilis'' (Hespell 1977) Shin et al. 2016 * ''Pseudomonas fluvialis, P. fluvialis'' Sudan et al. 2018 * ''Pseudomonas gelidicola, P. gelidicola'' Kadota 1951 (Approved Lists 1980) * "''Pseudomonas guezennei, P. guezennei''" Simon-Colin et al. 2008 * "''Pseudomonas halodenitrificans, P. halodenitrificans''" Alonso et al. 2001 * "''Pseudomonas halodurans, P. halodurans''" Cuhel et al. 1981 * "''Pseudomonas halosaccharolytica, P. halosaccharolytica''" Ohno et al. 1976 * "''Pseudomonas halosensibilis, P. halosensibilis''" Zou and Cai 1994 * "''Pseudomonas hydrogenothermophila, P. hydrogenothermophila''" Goto et al. 1978 * "''Pseudomonas hydrogenovora, P. hydrogenovora''" Igarashi et al. 1980 * ''Pseudomonas indica, P. indica'' Pandey et al. 2002 * "''Pseudomonas jinanensis, P. jinanensis''" Cai et al. 1989 * ''Pseudomonas kuykendallii, P. kuykendallii'' Hunter and Manter 2012 * "''Pseudomonas lopnurensis, P. lopnurensis''" Mamtimin et al. 2021 * "''Pseudomonas lubricans, P. lubricans''" Rehman et al. 2010 * ''Pseudomonas matsuisoli, P. matsuisoli'' Lin et al. 2015 * "''Pseudomonas melophthora, P. melophthora'' Allen and Riker 1932 * "''Pseudomonas mesoacidophila, P. mesoacidophila''" Kintaka et al. 1981 * "''Pseudomonas multiresinovorans, P. multiresinovorans''" Hernandez et al. 2008 * "''Pseudomonas perolens, P. perolens''" Szybalski 1950 * ''Pseudomonas pharmacofabricae, P. pharmacofabricae'' corrig. Yu et al. 2019 * "''Pseudomonas pratensis, P. pratensis''" Zhang et al. 2021 * ''Pseudomonas quercus, P. quercus'' Li et al. 2021 * "''Pseudomonas raguenesii, P. raguenesii''" Simon-Colin et al. 2009 * "''Pseudomonas reactans, P. reactans''" Preece and Wong 1982 * "''Pseudomonas reptilivora, P. reptilivora''" Caldwell and Ryerson 1940 * "''Pseudomonas rhizophila, P. rhizophila''" Hassen et al. 2018 * "''Pseudomonas rhizovicinus, P. rhizovicinus''" He et al. 2021 * "''Pseudomonas rubescens, P. rubescens''" Pivnick 1955 * ''Pseudomonas schmalbachii, P. schmalbachii'' Shelomi et al. 2021 * "''Pseudomonas septica, P. septica''" Bergey et al. 1930 * ''Pseudomonas sesami, P. sesami'' Madhaiyan et al. 2017 * "''Pseudomonas siderocapsa, P. siderocapsa''" Falamin and Pinevich 2006 * "''Pseudomonas suis, P. suis''" Woods 1930 * "''Pseudomonas tamsuii, P. tamsuii''" Liang et al. 2015 * ''Pseudomonas tarimensis, P. tarimensis'' Anwar et al. 2017 * "''Pseudomonas teessidea, P. teessidea''" Rahman et al. 2010 * "''Pseudomonas thermocarboxydovorans, P. thermocarboxydovorans''" Lyons et al. 1984 * ''Pseudomonas thermotolerans, P. thermotolerans'' Manaia and Moore 2002 * ''Pseudomonas tianjinensis, P. tianjinensis'' Chen et al. 2018 * ''Pseudomonas tohonis, P. tohonis'' Yamada et al. 2021 * "''Pseudomonas turbinellae, P. turbinellae''" Sreenivasan 1956 * ''Pseudomonas turukhanskensis, P. turukhanskensis'' Korshunova et al. 2016 * "''Pseudomonas tuticorinensis, P. tuticorinensis''" Sreenivasan 1956 * "''Pseudomonas wenzhouensis, P. wenzhouensis''" Zhang et al. 2021 * ''Pseudomonas xionganensis, P. xionganensis'' Zhao et al. 2020 * ''Pseudomonas yangonensis, P. yangonensis'' Tohya et al. 2020Species previously classified in the genus
Recently, 16S ribosomal RNA, 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'' and ''Ralstonia''. α proteobacteria: ''Sphingomonas abikonensis, P. abikonensis'', ''Aminobacter aminovorans, P. aminovorans'', ''Sphingomonas trueperi, P. azotocolligans'', ''Bradyrhizobium, P. carboxydohydrogena'', ''Oligotropha carboxidovorans, P. carboxidovorans'', ''Zavarzinia compransoris, P. compransoris'', ''Brevundimonas diminuta, P. diminuta'', ''Sphingomonas echinoides, P. echinoides'', ''Methylobacterium extorquens, P. extorquens'', ''Zymomonas mobilis, P. lindneri'', ''Methylobacterium mesophilicum, P. mesophilica'', ''Sphingomonas paucimobilis, P. paucimobilis'', ''Methylobacterium radiotolerans, P. radiora'', ''Methylobacterium rhodinum, P. rhodos'', ''Devosia riboflavina, P. riboflavina'', ''Methylobacterium extorquens, P. rosea'', ''Brevundimonas vesicularis, P. vesicularis''. β proteobacteria: ''Comamonas acidovorans, P. acidovorans'', ''Burkholderia gladioli, P. alliicola'', ''Burkholderia gladioli, P. antimicrobica'', ''Acidovorax avenae, P. avenae'', ''Thauera, P. butanovora'', ''Burkholderia caryophylli, P. caryophylli'', ''Acidovorax avenae, P. cattleyae'', ''Burkholderia cepacia, P. cepacia'', ''Burkholderia cocovenenans, P. cocovenenans'', ''Acidovorax delafieldii, P. delafieldii'', ''Acidovorax facilis, P. facilis'', ''Hydrogenophaga flava, P. flava'', ''Burkholderia gladioli, P. gladioli'', ''Burkholderia glathei, P. glathei'', ''Burkholderia glumae, P. glumae'', ''Herbaspirillum huttiense, P. huttiensis'', ''Vogesella indigofera, P. indigofera'', ''Curvibacter lanceolatus, P. lanceolata'', ''Paucimonas lemoignei, P. lemoignei'', ''Burkholderia mallei, B. mallei'', ''Janthinobacterium lividum, P. mephitica'', ''Telluria mixta, P. mixta'', ''Hydrogenophaga palleronii, P. palleronii'', ''Burkholderia phenazinium, P. phenazinium'', ''Ralstonia pickettii, P. pickettii'', ''Burkholderia plantarii, P. plantarii'', ''Hydrogenophaga pseudoflava, P. pseudoflava'', ''Burkholderia pseudomallei, B. pseudomallei'', ''Burkholderia pyrrocinia, P. pyrrocinia'', ''Acidovorax avenae, P. rubrilineans'', ''Herbaspirillum rubrisubalbicans, P. rubrisubalbicans'', ''Pelomonas saccharophila, P. saccharophila'', ''Ralstonia solanacearum, P. solanacearum'', ''Malikia spinosa, P. spinosa'', ''Ralstonia syzygii, P. syzygii'', ''Hydrogenophaga taeniospiralis, P. taeniospiralis'', ''Comamonas terrigena, P. terrigena'', ''Comamonas testosteroni, P. testosteroni''. γ-β proteobacteria: ''Pseudomonas boreopolis, P. boreopolis'', ''Xanthomonas, P. cissicola'', ''Stenotrophomonas, P. geniculata'', ''Stenotrophomonas maltophilia, P. hibiscicola'', ''Stenotrophomonas maltophilia, P. maltophilia'', ''Stenotrophomonas, P. pictorum''. γ proteobacteria: ''Chromohalobacter, P. beijerinckii'', ''Brevundimonas diminuta, P. diminuta'', ''Aeromonas, P. doudoroffii'', ''Microbulbifer elongatus, P. elongata'', ''Enterobacteriaceae, P. flectens'', ''Halomonas halodurans, P. marinus'', ''Halomonas utahensis, P. halophila'', ''Marinobacterium georgiense, P. iners'', ''Cobetia marina, P. marina'', ''Marinobacter nauticus, P. nautica'', ''Pseudoalteromonas nigrifaciens, P. nigrifaciens'', ''Acinetobacter, P. pavonacea'', ''Pseudoalteromonas piscicida, P. piscicida'', ''Marinobacterium stanieri, P. stanieri''. δ proteobacteria: ''Aeromonas caviae, P. formicans''.Phylogenetics
The following relationships between genomic affinity groups have been determined by phylogenetics, phylogenetic analysis:Bacteriophages
There are a number of bacteriophages that infect ''Pseudomonas'', e.g. * Pseudomonas phage Φ6, ''Pseudomonas'' phage Φ6 * Pseudomonas phage ΦCTX, ''Pseudomonas'' phage ΦCTX * Pseudomonas aeruginosa phage EL, ''Pseudomonas aeruginosa'' phage EL * Pseudomonas aeruginosa phage ΦKMV, ''Pseudomonas aeruginosa'' phage ΦKMV (a Phikmvvirus) * Pseudomonas aeruginosa phage LKD16, ''Pseudomonas aeruginosa'' phage LKD16 (a Phikmvvirus) * Pseudomonas aeruginosa phage LKA1, ''Pseudomonas aeruginosa'' phage LKA1 (a Phikmvvirus) * Pseudomonas aeruginosa phage LUZ19, ''Pseudomonas aeruginosa'' phage LUZ19 (a Phikmvvirus) * Pseudomonas aeruginosa phage ΦKZ, ''Pseudomonas aeruginosa'' phage ΦKZ * Pseudomonas virus gh1, ''Pseudomonas putida'' phage gh-1See also
* Culture collection for a list of culture collectionsFootnotes
References
External links
General