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Bioluminescent Bacteria
Bioluminescent bacteria are Bioluminescence, light-producing bacteria that are predominantly present in sea water, marine sediments, the surface of decomposing fish and in the gut of marine animals. While not as common, bacterial bioluminescence is also found in terrestrial and freshwater bacteria. These bacteria may be free living (such as ''Vibrio harveyi'') or in symbiosis with animals such as the Hawaiian Bobtail Squid, Hawaiian Bobtail squid (''Aliivibrio fischeri'') or terrestrial nematodes (''Photorhabdus luminescens''). The host organisms provide these bacteria a safe home and sufficient nutrition. In exchange, the hosts use the light produced by the bacteria for camouflage, prey and/or mate attraction. Bioluminescent bacteria have evolved symbiotic relationships with other organisms in which both participants benefit close to equally. Another possible reason bacteria use luminescence reaction is for quorum sensing, an ability to regulate gene expression in response to bacter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliphatic Compound
In organic chemistry, hydrocarbons ( compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. ''aleiphar'', fat, oil). Aliphatic compounds can be saturated, like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds, whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic. Structure Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds ( alkynes). If other elements (heteroatoms) are bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine, it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. The least complex aliphatic compound is methane (CH4). Properties Most aliphatic compounds are flammable, allowing the use of hydrocarbons as fuel, such as methane in Bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammaproteobacteria
Gammaproteobacteria is a class of bacteria in the phylum Pseudomonadota (synonym Proteobacteria). It contains about 250 genera, which makes it the most genera-rich taxon of the Prokaryotes. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. It is composed by all Gram-negative microbes and is the most phylogenetically and physiologically diverse class of Proteobacteria. These microorganisms can live in several terrestrial and marine environments, in which they play various important roles, including ''extreme environments'' such as hydrothermal vents. They generally have different shapes - rods, curved rods, cocci, spirilla, and filaments and include free living bacteria, biofilm formers, commensals and symbionts, some also have the distinctive trait of being bioluminescent. Metabolisms found in the different genera are very different; there are both aerobic and anaerobic (obligate or facultative) species, chemolithoautotrophic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterobacteriaceae
Enterobacteriaceae is a large family (biology), family of Gram-negative bacteria. It was first proposed by Rahn in 1936, and now includes over 30 genera and more than 100 species. Its classification above the level of family is still a subject of debate, but one classification places it in the order Enterobacterales of the class Gammaproteobacteria in the phylum Pseudomonadota. In 2016, the description and members of this family were emended based on comparative genomic analyses by Adeolu et al. Enterobacteriaceae includes, along with many harmless Symbiosis, symbionts, many of the more familiar pathogenic bacteria, pathogens, such as ''Salmonella'', ''Escherichia coli'', ''Klebsiella'', and ''Shigella''. Other disease-causing bacteria in this family include ''Enterobacter'' and ''Citrobacter''. Members of the Enterobacteriaceae can be Bacterial taxonomy#Nomenclature, trivially referred to as enterobacteria or "enteric bacteria",as several members live in the intestines of anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shewanellaceae
''Shewanella'' is the sole genus included in the marine bacteria family Shewanellaceae. Some species within it were formerly classed as ''Alteromonas''. ''Shewanella'' consists of facultatively anaerobic Gram-negative rods, most of which are found in extreme aquatic habitats where the temperature is very low and the pressure is very high. ''Shewanella'' bacteria are a normal component of the surface flora of fish and are implicated in fish spoilage. ''Shewanella chilikensis'', a species of the genus ''Shewanella'' commonly found in the marine sponges of Saint Martin's Island of the Bay of Bengal, Bangladesh. ''Shewanella oneidensis'' MR-1 is a widely used laboratory model to study anaerobic respiration of metals and other anaerobic extracellular electron acceptors, and for teaching about microbial electrogenesis and microbial fuel cells. Biochemical characteristics of ''Shewanella'' species Colony, morphological, physiological, and biochemical characteristics of ''Shewanell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vibrionaceae
The Vibrionaceae are a family of Pseudomonadota given their own order, Vibrionales. Inhabitants of fresh or salt water, several species are pathogenic, including the type species ''Vibrio cholerae'', which is the agent responsible for cholera. Most bioluminescent bacteria belong to this family, and are typically found as symbionts of deep-sea animals. Vibrionaceae are Gram-negative organisms and facultative anaerobes, capable of fermentation. They contain oxidase and have one or more flagella, which are generally polar. Originally, these characteristics defined the family, which was divided into four genera. Two of these, ''Vibrio'' and ''Photobacterium'', correspond to the modern group, although several new genera have been defined. Genetic studies have shown the other two original members—''Aeromonas'' and '' Plesiomonas''—belong to separate families. The family Vibrionaceae currently comprises eight validly published genera: ''Aliivibrio'', ''Catenococcus'', ''Ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quorum Sensing
In biology, quorum sensing or quorum signalling (QS) is the ability to detect and respond to cell population density by gene regulation. As one example, QS enables bacteria to restrict the expression of specific genes to the high cell densities at which the resulting phenotypes will be most beneficial. Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In a similar fashion, some social insects use quorum sensing to determine where to nest. Quorum sensing in pathogenic bacteria activates host immune signaling and prolongs host survival, by limiting the bacterial intake of nutrients, such as tryptophan, which further is converted to serotonin. As such, quorum sensing allows a Commensalism, commensal interaction between host and pathogenic bacteria. Quorum sensing may also be useful for cancer cell communications. In addition to its function in biological systems, quorum sensing has several useful applications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioluminescence
Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus ''Vibrio''; in others, it is autogenic, produced by the animals themselves. In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin. In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavin Mononucleotide
Flavin mononucleotide (FMN), or riboflavin-5′-phosphate, is a biomolecule produced from riboflavin (vitamin B2) by the enzyme riboflavin kinase and functions as the prosthetic group of various oxidoreductases, including NADH dehydrogenase, as well as cofactor in biological blue-light photo receptors. During the catalytic cycle, a reversible interconversion of the oxidized (FMN), semiquinone (FMNH•), and reduced (FMNH2) forms occurs in the various oxidoreductases. FMN is a stronger oxidizing agent than NAD and is particularly useful because it can take part in both one- and two-electron transfers. In its role as blue-light photo receptor, (oxidized) FMN stands out from the 'conventional' photo receptors as the signaling state and not an E/Z isomerization. It is the principal form in which riboflavin is found in cells and tissues. It requires more energy to produce, but is more soluble than riboflavin. In cells, FMN occurs freely circulating but also in several covalently b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldehyde
In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are common and play important roles in the technology and biological spheres. Structure and bonding Aldehydes feature a carbon center that is connected by a double bond to oxygen and a single bond to hydrogen and single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen. The central carbon is often described as being sp2- hybridized. The aldehyde group is somewhat polar. The C=O bond length is about 120-122 picometers. Physical properties and characterization Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes are more soluble in water, formaldehyde and acetaldehyde completely so. The volatile aldehydes have pungent odors. Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shewanella Oneidensis
''Shewanella oneidensis'' is a bacterium notable for its ability to reduce metal ions and live in environments with or without oxygen. This proteobacterium was first isolated from Lake Oneida, NY in 1988, hence its name. ''S. oneidensis'' is a facultative bacterium, capable of surviving and proliferating in both aerobic and anaerobic conditions. The special interest in ''S. oneidensis'' MR-1 revolves around its behavior in an anaerobic environment contaminated by heavy metals such as iron, lead and uranium. Experiments suggest it may reduce ionic mercury to elemental mercury and ionic silver to elemental silver. Cellular respiration for these bacteria is not restricted to heavy metals though; the bacteria can also target sulfates, nitrates and chromates when grown anaerobically. Name This species is referred to as ''S. oneidensis'' MR-1, indicating "manganese reducing", a special feature of this organism. It is a common misconception to think that MR-1 refers to "metal-reduc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vibrio
''Vibrio'' is a genus of Gram-negative bacteria, possessing a curved-rod (comma) shape, several species of which can cause foodborne infection, usually associated with eating undercooked seafood. Being highly salt tolerant and unable to survive in fresh water, ''Vibrio'' spp. are commonly found in various salt water environments. ''Vibrio'' spp. are facultative anaerobes that test positive for oxidase and do not form spores. All members of the genus are motile. They are able to have polar or lateral flagellum with or without sheaths. ''Vibrio'' species typically possess two chromosomes, which is unusual for bacteria. Each chromosome has a distinct and independent origin of replication, and are conserved together over time in the genus. Recent phylogenies have been constructed based on a suite of genes (multilocus sequence analysis). O. F. Müller (1773, 1786) described eight species of the genus ''Vibrio'' (included in Infusoria), three of which were spirilliforms. Some of the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
