Taxonomy Citation ID | Reference |
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9924 | Wieringa, K.T. "The formation of acetic acid from carbon dioxide and hydrogen by anaerobic spore-forming bacteria." Antonie van Leeuwenhoek J. Microbiol. Serol. (1940) 6:251-262. [No PubMed record available.] |
4082 | Gottschalk, G., and Braun, M. "Revival of the name Clostridium aceticum." Int. J. Syst. Bacteriol. (1981) 31:476. [No PubMed record available.] | 43545 |
Poehlein A,
Cebulla M,
Ilg MM,
Bengelsdorf FR,
Schiel-Bengelsdorf B,
Whited G,
Andreesen JR,
Gottschalk G,
Daniel R,
Dürre P,
( 2015 ) The Complete Genome Sequence of Clostridium aceticum: a Missing Link between Rnf- and Cytochrome-Containing Autotrophic Acetogens. PMID : 26350967 DOI : 10.1128/mBio.01168-15 PMC : PMC4600107 Abstract >>
Clostridium aceticum was the first isolated autotrophic acetogen, converting CO2 plus H2 or syngas to acetate. Its genome has now been completely sequenced and consists of a 4.2-Mbp chromosome and a small circular plasmid of 5.7 kbp. Sequence analysis revealed major differences from other autotrophic acetogens. C. aceticum contains an Rnf complex for energy conservation (via pumping protons or sodium ions). Such systems have also been found in C. ljungdahlii and Acetobacterium woodii. However, C. aceticum also contains a cytochrome, as does Moorella thermoacetica, which has been proposed to be involved in the generation of a proton gradient. Thus, C. aceticum seems to represent a link between Rnf- and cytochrome-containing autotrophic acetogens. In C. aceticum, however, the cytochrome is probably not involved in an electron transport chain that leads to proton translocation, as no genes for quinone biosynthesis are present in the genome. Autotrophic acetogenic bacteria are receiving more and more industrial focus, as CO2 plus H2 as well as syngas are interesting new substrates for biotechnological processes. They are both cheap and abundant, and their use, if it results in sustainable products, also leads to reduction of greenhouse gases. Clostridium aceticum can use both gas mixtures, is phylogenetically not closely related to the commonly used species, and may thus become an even more attractive workhorse. In addition, its energy metabolism, which is characterized here, and the ability to synthesize cytochromes might offer new targets for improving the ATP yield by metabolic engineering and thus allow use of C. aceticum for production of compounds by pathways that currently present challenges for energy-limited acetogens.
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