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 sandwiched between an inner membrane (cytoplasmic), and an outer membrane.
Acidobacteriota is a phylum of Gram-negative bacteria. Its members are physiologically diverse and ubiquitous, especially in soils, but are under-represented in culture.
Mollicutes is a class of bacteria distinguished by the absence of a cell wall. The word "Mollicutes" is derived from the Latin mollis, and cutis. Individuals are very small, typically only 0.2–0.3 μm in size and have a very small genome size. They vary in form, although most have sterols that make the cell membrane somewhat more rigid. Many are able to move about through gliding, but members of the genus Spiroplasma are helical and move by twisting. The best-known genus in the Mollicutes is Mycoplasma. Colonies show the typical "fried-egg" appearance.
Acidilobales are an order of archaea in the class Thermoprotei.
Pyrobaculum is a genus of the Thermoproteaceae.
In taxonomy, Vulcanisaeta is a genus of the Thermoproteaceae.
Pyrococcus is a genus of Thermococcaceaen archaean.
Halorubrum is a genus in the family Halorubraceae. Halorubrum species areusually halophilic and can be found in waters with high salt concentration such as the Dead Sea or Lake Zabuye.
Deinococcus is in the monotypic family Deinococcaceae, and one genus of three in the order Deinococcales of the bacterial phylum Deinococcota highly resistant to environmental hazards. These bacteria have thick cell walls that give them Gram-positive stains, but they include a second membrane and so are closer in structure to Gram-negative bacteria. Deinococcus survive when their DNA is exposed to high doses of gamma and UV radiation. Whereas other bacteria change their structure in the presence of radiation, such as by forming endospores, Deinococcus tolerate it without changing their cellular form and do not retreat into a hardened structure. They are also characterized by the presence of the carotenoid pigment deinoxanthin that give them their pink color. They are usually isolated according to these two criteria. In August 2020, scientists reported that bacteria from Earth, particularly Deinococcus bacteria, were found to survive for three years in outer space, based on studies conducted on the International Space Station. These findings support the notion of panspermia, the hypothesis that life exists throughout the Universe, distributed in various ways, including space dust, meteoroids, asteroids, comets, planetoids or contaminated spacecraft.
Elusimicrobium minutum is an ultramicrobacterium and first accepted member to be cultured of a major bacterial lineage previously known only as candidate phylum Termite Gut 1 (TG1), which has accordingly been renamed phylum Elusimicrobiota. It was isolated in the laboratory of Andreas Brune at the Max Planck Institute for Terrestrial Microbiology, from the scarab beetle. It is a mesophilic, obligately anaerobic ultramicrobacterium with a gram-negative cell envelope. Cells are typically rod shaped, but cultures are pleomorphic in all growth phases. The isolate grows heterotrophically on sugars and ferments D-galactose, D-glucose, D-fructose, D-glucosamine, and N-acetyl-D-glucosamine to acetate, ethanol, hydrogen, and alanine as major products but only if amino acids are present in the medium
Afifella is a genus in the phylum Pseudomonadota (Bacteria). Afifella are found in marine and estuarine settings, including microbial mats. They are anaerobes, with one cultured representative capable of photosynthesis.
Geobacillus thermoglucosidasius is a thermophilic gram-positive bacterium, and a member of the Bacillota phylum. It was first isolated from soil in Japan in 1983.
Filobacillus milensis is a species of halophilic spore-forming bacteria, the type and only current species of its genus. Its cells are motile, strictly aerobic rods which stain Gram-negative. Its type strain is SH 714T.
Lactiplantibacillus fabifermentans is a member of the genus Lactiplantibacillus and a type of lactic acid bacteria (LAB), a group of Gram-positive bacteria that produce lactic acid as their major fermented end product and that are often involved in food fermentation. L. fabifermentans was proposed in 2009 as a new species, after the type strain LMG 24284T has been isolated from Ghanaian cocoa fermentation. Analysis of the 16S rRNA gene sequence demonstrated that this species is a member of the Lactobacillus plantarum species group but further analysis demonstrated that it is possible to differentiate it from the nearest neighbors by means of DNA-DNA hybridization experiments, pheS sequence analysis, whole-cell protein electrophoresis, fluorescent amplified fragment length polymorphism analysis and biochemical characterization.
Cryptobacterium curtum is a Gram-positive anaerobic rod bacteria isolated from human mouths.
Trueperella pyogenes is a species of nonmotile, facultatively anaerobic, Gram-positive bacteria. The cells typically measure 0.5 by 2.0 μm. They appear as pleomorphic or coccoid rods. They tend to be grouped singly or in short chains but are sometimes grouped into V-shaped pairs.
Brevinema andersonii, named for John F. Anderson, who first described the organism. This organism is a Gram-negative, microaerophilic, helical shaped, chemoorganotrophic organism from the genus Brevinema. Brevinema andersonii is host associated, strains have been isolated from blood and other tissues of short-tailed shrews and white-footed mice and are infectious for laboratory mice and Syrian hamsters.B. andersonii is readily identified by restriction enzyme analysis, and SDS-PAGE, or fatty acid composition data. Another identifier for B. andersonii is the sheathed periplasmic flagella in the 1-2-1 configuration. While cells are visible by dark-field or phase-contrast microscopy, they cannot be seen when bright-field microscopy is used.
Propionispira raffinosivorans is a motile, obligate anaerobic, gram-negative bacteria. It was originally isolated from spoiled beer and believed to have some causative effect in beer spoilage. Since then, it has been taxonomically reclassified and proven to play a role in anaerobic beer spoilage, because of its production of acids, such as acetic and propionic acid, during fermentation
Vibrio aerogenes is a gram-negative organism that is rod-shaped and has a two-sheathed flagella that is found on one side of the cell that makes it motile. When it is grown on polypeptone-yeast (PY) plate medium, the colonies are usually round and flat. It is an organism that is mesophilic which means it likes temperatures that are between 20-45°C. In addition, it is facultatively anaerobic, which means it can survive with or without oxygen. This is a marine bacteria that is most commonly found in temperatures between 30°C and 35°C and pH 6-7. It requires Na+ to grow and this is what makes the marine environment a necessity for this organism. V. aerogenes can ferment glucose and a few other carbohydrates to yield organic acids.
Bacteroides caccae is a saccharolytic gram-negative bacterium from the genus Bacteroides. They are obligate anaerobes first isolated from human feces in the 1980s. Prior to their discovery, they were known as the 3452A DNA homology group. The type strain is now identified as ATCC 43185.
