@article {3149, title = {The genome of Pelobacter carbinolicus reveals surprising metabolic capabilities and physiological features.}, journal = {BMC Genomics}, volume = {13}, year = {2012}, month = {2012 Dec 10}, pages = {690}, abstract = {

BACKGROUND: The bacterium Pelobacter carbinolicus is able to grow by fermentation, syntrophic hydrogen/formate transfer, or electron transfer to sulfur from short-chain alcohols, hydrogen or formate; it does not oxidize acetate and is not known to ferment any sugars or grow autotrophically. The genome of P. carbinolicus was sequenced in order to understand its metabolic capabilities and physiological features in comparison with its relatives, acetate-oxidizing Geobacter species.

RESULTS: Pathways were predicted for catabolism of known substrates: 2,3-butanediol, acetoin, glycerol, 1,2-ethanediol, ethanolamine, choline and ethanol. Multiple isozymes of 2,3-butanediol dehydrogenase, ATP synthase and [FeFe]-hydrogenase were differentiated and assigned roles according to their structural properties and genomic contexts. The absence of asparagine synthetase and the presence of a mutant tRNA for asparagine encoded among RNA-active enzymes suggest that P. carbinolicus may make asparaginyl-tRNA in a novel way. Catabolic glutamate dehydrogenases were discovered, implying that the tricarboxylic acid (TCA) cycle can function catabolically. A phosphotransferase system for uptake of sugars was discovered, along with enzymes that function in 2,3-butanediol production. Pyruvate:ferredoxin/flavodoxin oxidoreductase was identified as a potential bottleneck in both the supply of oxaloacetate for oxidation of acetate by the TCA cycle and the connection of glycolysis to production of ethanol. The P. carbinolicus genome was found to encode autotransporters and various appendages, including three proteins with similarity to the geopilin of electroconductive nanowires.

CONCLUSIONS: Several surprising metabolic capabilities and physiological features were predicted from the genome of P. carbinolicus, suggesting that it is more versatile than anticipated.

}, keywords = {Base Pairing, Base Sequence, Butylene Glycols, Choline, Deltaproteobacteria, Ethanolamine, Ethylene Glycol, Genome, Bacterial, Glycerol, Metabolic Networks and Pathways, Molecular Sequence Annotation, Molecular Sequence Data, Mutation, Oxidation-Reduction, Oxidoreductases, Propylene Glycols, RNA, Transfer, Asn, Sequence Analysis, DNA}, issn = {1471-2164}, doi = {10.1186/1471-2164-13-690}, author = {Aklujkar, Muktak and Haveman, Shelley A and DiDonato, Raymond and Chertkov, Olga and Han, Cliff S and Land, Miriam L and Brown, Peter and Lovley, Derek R} } @article {639, title = {Fe(III) and S0 reduction by Pelobacter carbinolicus.}, journal = {Appl Environ Microbiol}, volume = {61}, year = {1995}, month = {1995 Jun}, pages = {2132-8}, abstract = {There is a close phylogenetic relationship between Pelobacter species and members of the genera Desulfuromonas and Geobacter, and yet there has been a perplexing lack of physiological similarities. Pelobacter species have been considered to have a fermentative metabolism. In contrast, Desulfuromonas and Geobacter species have a respiratory metabolism with Fe(III) serving as the common terminal electron acceptor in all species. However, the ability of Pelobacter species to reduce Fe(III) had not been previously evaluated. When a culture of Pelobacter carbinolicus that had grown by fermentation of 2,3-butanediol was inoculated into the same medium supplemented with Fe(III), the Fe(III) was reduced. There was less accumulation of ethanol and more production of acetate in the presence of Fe(III). P. carbinolicus grew with ethanol as the sole electron donor and Fe(III) as the sole electron acceptor. Ethanol was metabolized to acetate. Growth was also possible on Fe(III) with the oxidation of propanol to propionate or butanol to butyrate if acetate was provided as a carbon source. P. carbinolicus appears capable of conserving energy to support growth from Fe(III) respiration as it also grew with H2 or formate as the electron donor and Fe(III) as the electron acceptor. Once adapted to Fe(III) reduction, P. carbinolicus could also grow on ethanol or H2 with S0 as the electron acceptor. P. carbinolicus did not contain detectable concentrations of the c-type cytochromes that previous studies have suggested are involved in electron transport to Fe(III) in other organisms that conserve energy to support growth from Fe(III) reduction.(ABSTRACT TRUNCATED AT 250 WORDS)}, keywords = {Bacteria, Anaerobic, Base Sequence, Butylene Glycols, Culture Media, Ethanol, Ferrous Compounds, Hydrogen, Molecular Sequence Data, Oxidation-Reduction, Phylogeny, RNA, Ribosomal, 16S, Sulfur}, issn = {0099-2240}, author = {Lovley, D R and Phillips, E J and Lonergan, D J and Widman, P K} }