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Taxa In Disguise
In bacteriology, a taxon in disguise is a species, genus or higher unit of biological classification whose evolutionary history reveals has evolved from another unit of a similar or lower rank, making the parent unit paraphyletic. That happens when rapid evolution makes a new species appear so radically different from the ancestral group that it is not (initially) recognised as belonging to the parent phylogenetic group, which is left as an evolutionary grade. While the term is from bacteriology, parallel examples are found throughout the tree of life. For example, four-footed animals have evolved from piscine ancestors but since they are not generally considered fish, they can be said to be "fish in disguise". In many cases, the paraphyly can be resolved by reclassifying the taxon in question under the parent group. However, in bacteriology, since renaming groups may have serious consequences since by causing confusion over the identity of pathogens, it is generally avoided for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriology
Bacteriology is the branch and specialty of biology that studies the morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the identification, classification, and characterization of bacterial species. Because of the similarity of thinking and working with microorganisms other than bacteria, such as protozoa, fungi, and viruses, there has been a tendency for the field of bacteriology to extend as microbiology. The terms were formerly often used interchangeably. However, bacteriology can be classified as a distinct science. Overview Definition Bacteriology is the study of bacteria and their relation to medicine. Bacteriology evolved from physicians needing to apply the germ theory to address the concerns relating to disease spreading in hospitals the 19th century. Identification and characterizing of bacteria being associated to diseases led to advances in pathogenic bacteriology. K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escherichia Coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escherichia'' that is commonly found in the lower intestine of warm-blooded organisms. Most ''E. coli'' strains are harmless, but some serotypes ( EPEC, ETEC etc.) can cause serious food poisoning in their hosts, and are occasionally responsible for food contamination incidents that prompt product recalls. Most strains do not cause disease in humans and are part of the normal microbiota of the gut; such strains are harmless or even beneficial to humans (although these strains tend to be less studied than the pathogenic ones). For example, some strains of ''E. coli'' benefit their hosts by producing vitamin K2 or by preventing the colonization of the intestine by pathogenic bacteria. These mutually beneficial relationships between ''E. col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azomonas Macrocytogenes
''Azomonas'' species are typically motile, oval to spherical, and secrete large quantities of capsular slime. They are distinguished from ''Azotobacter'' by their inability to form cysts, but like ''Azotobacter'', they can biologically fix nitrogen under aerobic conditions (diazotrophs). Bacteria of the genus ''Azomonas'' are known to form intracellular inclusions of polyhydroxyalkanoates under certain environmental conditions (e.g. lack of elements such as phosphorus, nitrogen, or oxygen combined with an excessive supply of carbon sources). Etymology The name ''Azomonas'' derives from: : New Latin noun ''azotum'' Greek_noun_ζωή,_''zōē'',_life;_Greek_language.html" "title="Ancient_Greek_language.html" "title="Ancient_Greek_language.html" "title="rom Fr. noun ''azote'' (from Ancient Greek language">Greek prep. ά, ''a'', not; Ancient Greek language">Greek noun ζωή, ''zōē'', life; Greek language">Greek Greek may refer to: Greece Anything of, from, or related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotobacter
''Azotobacter'' is a genus of usually motile, oval or spherical bacteria that form thick-walled cysts (and also has hard crust) and may produce large quantities of capsular slime. They are aerobic, free-living soil microbes that play an important role in the nitrogen cycle in nature, binding atmospheric nitrogen, which is inaccessible to plants, and releasing it in the form of ammonium ions into the soil (nitrogen fixation). In addition to being a model organism for studying diazotrophs, it is used by humans for the production of biofertilizers, food additives, and some biopolymers. The first representative of the genus, ''Azotobacter chroococcum'', was discovered and described in 1901 by Dutch microbiologist and botanist Martinus Beijerinck. ''Azotobacter'' species are Gram-negative bacteria found in neutral and alkaline soils, in water, and in association with some plants. Biological characteristics Morphology Cells of the genus ''Azotobacter'' are relatively large for b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonas
''Pseudomonas'' is a genus of Gram-negative, Gammaproteobacteria, belonging to the family Pseudomonadaceae and containing 191 described species. The members of the genus demonstrate a great deal of metabolic diversity and consequently are able to colonize a wide range of niches. Their ease of culture ''in vitro'' and availability of an increasing number of ''Pseudomonas'' strain genome sequences has made the genus an excellent focus for scientific research; the best studied species include ''P. aeruginosa'' in its role as an opportunistic human pathogen, the plant pathogen '' P. syringae'', the soil bacterium '' P. putida'', and the plant growth-promoting ''P. fluorescens, 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. The generic name ''Pseudomonas'' created for these organisms was defined in rather vague terms by Walter Migula i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthrax
Anthrax is an infection caused by the bacterium ''Bacillus anthracis''. It can occur in four forms: skin, lungs, intestinal, and injection. Symptom onset occurs between one day and more than two months after the infection is contracted. The skin form presents with a small blister with surrounding swelling that often turns into a painless ulcer with a black center. The inhalation form presents with fever, chest pain and shortness of breath. The intestinal form presents with diarrhea (which may contain blood), abdominal pains, nausea and vomiting. The injection form presents with fever and an abscess at the site of drug injection. According to the USA's Centers for Disease Control and Prevention, the first clinical descriptions of cutaneous anthrax were given by Maret in 1752 and Fournier in 1769. Before that anthrax had been described only through historical accounts. The Prussian scientist Robert Koch (1843–1910) was the first to identify ''Bacillus anthracis'' as the bacteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmid
A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria; however, plasmids are sometimes present in archaea and eukaryotic organisms. In nature, plasmids often carry genes that benefit the survival of the organism and confer selective advantage such as antibiotic resistance. While chromosomes are large and contain all the essential genetic information for living under normal conditions, plasmids are usually very small and contain only additional genes that may be useful in certain situations or conditions. Artificial plasmids are widely used as vectors in molecular cloning, serving to drive the replication of recombinant DNA sequences within host organisms. In the laboratory, plasmids may be introduced into a cell via transformation. Synthetic plasmids are available for procurement over the inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Medusa
''Bacillus'' (Latin "stick") is a genus of Gram-positive, rod-shaped bacteria, a member of the phylum ''Bacillota'', with 266 named species. The term is also used to describe the shape (rod) of other so-shaped bacteria; and the plural ''Bacilli'' is the name of the class of bacteria to which this genus belongs. ''Bacillus'' species can be either obligate aerobes which are dependent on oxygen, or facultative anaerobes which can survive in the absence of oxygen. Cultured ''Bacillus'' species test positive for the enzyme catalase if oxygen has been used or is present. ''Bacillus'' can reduce themselves to oval endospores and can remain in this dormant state for years. The endospore of one species from Morocco is reported to have survived being heated to 420 °C. Endospore formation is usually triggered by a lack of nutrients: the bacterium divides within its cell wall, and one side then engulfs the other. They are not true spores (i.e., not an offspring). Endospore formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Weihenstephanensis
''Bacillus mycoides'' is a bacterium of the genus ''Bacillus''. Like other ''Bacillus'' species, ''B. mycoides'' is Gram positive, rod-shaped, and forms spores. ''B. mycoides'' is distinguished from other ''Bacillus'' species by its unusual growth on agar plates, where it forms expansive hairy colonies with characteristic swirls. Description ''B. mycoides'' are rod-shaped cells about 1 micron across and 3 to 5 microns long. When growing, they either grow as single cells or form loosely connected chains of cells. They are not motile. ''B. mycoides'' can survive with or without oxygen and grows at temperatures ranging from 10 to 15 °C to 35–40 °C. ''B. mycoides'' is distinguished from a number of other ''Bacillus'' species in the unusual morphology of the colonies it forms when grown on agar plates. ''B. mycoides'' forms white opaque colonies that are characteristically hairy in appearance (often referred to as "rhizoid"). These colonies rapidly spread to fill the pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Pseudomycoides
''Bacillus pseudomycoides'' is a bacterium. The type strain is NRRL B-617T. References Further reading * * External links *LPSN pseudomycoides Bacteria described in 1998 {{bacilli-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Mycoides
''Bacillus mycoides'' is a bacterium of the genus ''Bacillus''. Like other ''Bacillus'' species, ''B. mycoides'' is Gram positive, rod-shaped, and forms spores. ''B. mycoides'' is distinguished from other ''Bacillus'' species by its unusual growth on agar plates, where it forms expansive hairy colonies with characteristic swirls. Description ''B. mycoides'' are rod-shaped cells about 1 micron across and 3 to 5 microns long. When growing, they either grow as single cells or form loosely connected chains of cells. They are not motile. ''B. mycoides'' can survive with or without oxygen and grows at temperatures ranging from 10 to 15 °C to 35–40 °C. ''B. mycoides'' is distinguished from a number of other ''Bacillus'' species in the unusual morphology of the colonies it forms when grown on agar plates. ''B. mycoides'' forms white opaque colonies that are characteristically hairy in appearance (often referred to as "rhizoid"). These colonies rapidly spread to fill the pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Thuringiensis
''Bacillus thuringiensis'' (or Bt) is a gram-positive, soil-dwelling bacterium, the most commonly used biological pesticide worldwide. ''B. thuringiensis'' also occurs naturally in the gut of caterpillars of various types of moths and butterflies, as well on leaf surfaces, aquatic environments, animal feces, insect-rich environments, and flour mills and grain-storage facilities. It has also been observed to parasitize other moths such as ''Cadra calidella''—in laboratory experiments working with ''C. calidella'', many of the moths were diseased due to this parasite. During sporulation, many Bt strains produce crystal proteins (proteinaceous inclusions), called delta endotoxins, that have insecticidal action. This has led to their use as insecticides, and more recently to genetically modified crops using Bt genes, such as Bt corn. Many crystal-producing Bt strains, though, do not have insecticidal properties. The subspecies ''israelensis'' is commonly used for control of mosq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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