''Geobacter metallireducens'' is a

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 ...

proteobacterium Pseudomonadota (synonym Proteobacteria) is a major phylum of Gram-negative bacteria. The renaming of phyla in 2021 remains controversial among microbiologists, many of whom continue to use the earlier names of long standing in the literature. The ...

. It is a strict anaerobe that oxidizes several short-chain

fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, fr ...

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

s, and monoaromatic compounds with Fe(III) as the sole

electron acceptor An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process. Electron acceptors are sometimes mista ...

. It can also use

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

for its growth and convert U(VI) to U(IV). ''Geobacter metallireducens'' was discovered by Derek Lovley at

UMass Amherst The University of Massachusetts Amherst (UMass Amherst, UMass) is a public research university in Amherst, Massachusetts and the sole public land-grant university in Commonwealth of Massachusetts. Founded in 1863 as an agricultural college, it ...

in 1993. It is an iron-reducing bacteria and it has been thought that the microbe could be used to treat industrial sites where "cyanide-metal complexes" have formed to contaminate the site. ''Geobacter metallireducens'' becomes motile when necessary, producing a flagellum in order to relocate when environmental conditions become unfavorable. The genome of ''Geobacter metallireducens'' has a chromosome length of 3,997,420 bp. It has a

circular bacterial chromosome A circular chromosome is a chromosome in bacteria, archaea, mitochondria, and chloroplasts, in the form of a molecule of circular DNA, unlike the linear chromosome of most eukaryotes. Most prokaryote chromosomes contain a circular DNA molecu ...

, meaning there are no free ends of DNA. The shape is roughly like that of an egg. ''Geobacter metallireducens'' also has a

GC content In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out o ...

of 59.51%. The

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; how ...

has a lower

, of 52.48%, and is 13,762 bp in length. The plasmid encodes a stabilizing protein, RelE/ParE, which allows ''Geobacter metallireducens'' to adapt and thrive in different and new environmental conditions. ''G. metallireducens'' has been demonstrated to reduce

chloramphenicol Chloramphenicol is an antibiotic useful for the treatment of a number of bacterial infections. This includes use as an eye ointment to treat conjunctivitis. By mouth or by injection into a vein, it is used to treat meningitis, plague, cholera, a ...

(CAP) to complete dechlorination products under pure culture conditions. Research utilizing cyclic voltammograms and

chronoamperometry Chronoamperometry is an electrochemical technique in which the potential of the working electrode is stepped and the resulting current from faradaic processes occurring at the electrode (caused by the potential step) is monitored as a function of ...

revealed that the bacteria exhibited a negative correlation CAP removal efficiency with initial CAP dosages, displaying the organism's potential application of

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 ...

in environments polluted by antibiotics.Xu, H., Xiao, L., Zheng, S. et al. "Reductive degradation of chloramphenicol by Geobacter metallireducens". ''Sci. China Technol. Sci.'' 62, 1688–1694 (2019).

References

External links

''Geobacter''
at the

LPSN List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy of prokaryotes, following the taxonomy requirements and rulings of the International Code of Nomenclature ...

*
Type strain of ''Geobacter metallireducens'' at Bac''Dive'' – the Bacterial Diversity Metadatabase
{{DEFAULTSORT:Geobacter metallireducens Thermodesulfobacteriota Bacteria described in 1993

See also

References

Further reading

External links