Dataset Information

Unexpected specificity of interspecies cobamide transfer from Geobacter spp. to organohalide-respiring Dehalococcoides mccartyi strains.

ABSTRACT: Dehalococcoides mccartyi strains conserve energy from reductive dechlorination reactions catalyzed by corrinoid-dependent reductive dehalogenase enzyme systems. Dehalococcoides lacks the ability for de novo corrinoid synthesis, and pure cultures require the addition of cyanocobalamin (vitamin B(12)) for growth. In contrast, Geobacter lovleyi, which dechlorinates tetrachloroethene to cis-1,2-dichloroethene (cis-DCE), and the nondechlorinating species Geobacter sulfurreducens have complete sets of cobamide biosynthesis genes and produced 12.9 ± 2.4 and 24.2 ± 5.8 ng of extracellular cobamide per liter of culture suspension, respectively, during growth with acetate and fumarate in a completely synthetic medium. G. lovleyi-D. mccartyi strain BAV1 or strain FL2 cocultures provided evidence for interspecies corrinoid transfer, and cis-DCE was dechlorinated to vinyl chloride and ethene concomitant with Dehalococcoides growth. In contrast, negligible increase in Dehalococcoides 16S rRNA gene copies and insignificant dechlorination occurred in G. sulfurreducens-D. mccartyi strain BAV1 or strain FL2 cocultures. Apparently, G. lovleyi produces a cobamide that complements Dehalococcoides' nutritional requirements, whereas G. sulfurreducens does not. Interestingly, Dehalococcoides dechlorination activity and growth could be restored in G. sulfurreducens-Dehalococcoides cocultures by adding 10 ?M 5',6'-dimethylbenzimidazole. Observations made with the G. sulfurreducens-Dehalococcoides cocultures suggest that the exchange of the lower ligand generated a cobalamin, which supported Dehalococcoides activity. These findings have implications for in situ bioremediation and suggest that the corrinoid metabolism of Dehalococcoides must be understood to faithfully predict, and possibly enhance, reductive dechlorination activities.

SUBMITTER: Yan J

PROVIDER: S-EPMC3426716 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Unexpected specificity of interspecies cobamide transfer from Geobacter spp. to organohalide-respiring Dehalococcoides mccartyi strains.

Yan Jun J Ritalahti Kirsti M KM Wagner Darlene D DD Löffler Frank E FE

Applied and environmental microbiology 20120706 18

Dehalococcoides mccartyi strains conserve energy from reductive dechlorination reactions catalyzed by corrinoid-dependent reductive dehalogenase enzyme systems. Dehalococcoides lacks the ability for de novo corrinoid synthesis, and pure cultures require the addition of cyanocobalamin (vitamin B(12)) for growth. In contrast, Geobacter lovleyi, which dechlorinates tetrachloroethene to cis-1,2-dichloroethene (cis-DCE), and the nondechlorinating species Geobacter sulfurreducens have complete sets of ...[more]

PMID: 22773645

Similar Datasets

Project description:The strictly anaerobic bacterium Dehalococcoides mccartyi is obligatory dependent on organohalide respiration for energy conservation and growth. Due to its capability to reductively dehalogenate a multitude of toxic halogenated electron acceptors, it plays an important role in the attenuation of these compounds at respective contaminated sites. Here, D. mccartyi strain CBDB1, specialized on the dehalogenation of chloroaromatic compounds, was grown in a two-liquid phase system with 1,2,3-trichlorobenzene as electron acceptor, acetate plus CO2 as carbon source and hydrogen as electron donor. The proteome and Nε-lysine acetylome were analyzed in the lag, exponential and stationary phases. The high and almost invariable abundance of the membrane-localized organohalide respiration complex consisting of the reductive dehalogenases CbrA and CbdbA80, the uptake hydrogenase HupLS and the organohalide respiration molybdoenzyme OmeAB was shown throughout growth and also after a prolonged stationary phase. Quantification of transcripts of reductive dehalogenase genes revealed their major synthesis starting in the lag phase, which might be a prerequisite for balanced growth in the exponential phase. The analyses of the coverage of functional pathways as well as indicator analysis revealed the growth-phase specificity of the proteome, with regulatory proteins identified as important indicators for the stationary phase. The number of acetylated proteins increased from the lag to the stationary phase. We detected pronounced acetylation of key proteins of the acetate metabolism, i.e. the synthesis of acetyl-CoA and its processing via gluconeogenesis and the incomplete Wood-Ljungdahl pathway, as well as of proteins central for the biosynthesis of amino acids, co-factors and terpenoids. In addition, the partial acetylation of the reductive dehalogenases as well as of TatA, a component of the twin-arginine translocation machinery, suggests that acetylation might be directly involved in the maintenance of the organohalide respiration capacity of D. mccartyi over periods without access to halogenated electron acceptors.

Dataset Information

Unexpected specificity of interspecies cobamide transfer from Geobacter spp. to organohalide-respiring Dehalococcoides mccartyi strains.

Publications

Unexpected specificity of interspecies cobamide transfer from Geobacter spp. to organohalide-respiring Dehalococcoides mccartyi strains.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure