Vitamin B as a source of variability in isotope effects for chloroform biotransformation by Dehalobacter.

Carbon and chlorine isotope effects for biotransformation of chloroform by different microbes show significant variability. Reductive dehalogenases (RDase) enzymes contain different cobamides, affecting substrate preferences, growth yields, and dechlorination rates and extent. We investigate the role of cobamide type on carbon and chlorine isotopic signals observed during reductive dechlorination of chloroform by the RDase CfrA.

Characterization of anaerobic biotransformation of hexachlorocyclohexanes by novel microbial consortia enriched from channel and river sediments.

The microbial biotransformation of hexachlorocyclohexane (HCH) by novel anaerobic microbial consortia enriched from sediments of an industrial effluent channel and the river Ravi in Pakistan was examined. The anaerobic consortia were capable of biotransforming α-, β-, γ-, and δ-HCH through reductive dichloroelimination, resulting in the formation of benzene and monochlorobenzene. Concerning γ-HCH biotransformation by the channel and river cultures, isotopic fractionations for carbon (ε) were - 5.

Anaerobic biotransformation of hexachlorocyclohexane isomers in aqueous condition: Dual CCl isotope fractionation and impact on microbial community compositions.

Hexachlorocyclohexane (HCH) isomers are persistent organic pollutants (POPs) with high toxicity, lipid solubility, chemical stability. Despite the current ban on usage of Lindane, residual contamination cannot be ignored, and HCH are frequently detected in groundwater and threaten human health. Cultures capable of degrading α-HCH, β-HCH, γ-HCH, and δ-HCH individually have been enriched in anoxic aqueous conditions.

Characterization of Hexachlorocyclohexane Isomer Dehydrochlorination by LinA1 and LinA2 Using Multi-element Compound-Specific Stable Isotope Analysis.

Dehydrochlorination is one of the main (thus far discovered) processes for aerobic microbial transformation of hexachlorocyclohexane (HCH) which is mainly catalyzed by LinA enzymes. In order to gain a better understanding of the reaction mechanisms, multi-element compound-specific stable isotope analysis was applied for evaluating α- and γ-HCH transformations catalyzed by LinA1 and LinA2 enzymes. The isotopic fractionation (ε) values for particular elements of (+)α-HCH (ε = -10.