Anaerobic Bacteria Degrading Low Molecular Chlorinated Fatty Acids and Related Compounds

Two anaerobic rod-shaped bacteria, strains K-1 and ACR were isolated from mesophilic digester sludge acclimatized with 4-chlorobutyrate or acrylate as the main energy and carbon source. Both bacteria have tentatively been classified in the genus Clostridium because of their cell morphology and spore formation. Strain K-1 could utilize chlorinated compounds such as 4- and 3-chlorobutyrate and 3-chloropropionate, and the main products were butyrate and acetate, propionate and acetate, respectively. Crotonate and 3-hyflroxybutyrate could be also degraded by strain K-1 and the same products from the degradation of 4-chlorobutyrate were observed. Strain ACR could utilize acrylate to produce propionate and acetate. It could also utilize chlorinated fatty acids such as 4-chlorobutyrate and 3-chloropropionate. However, neither of the strains could utilize saturated fatty acids such as propionate and butyrate. Reductive dechlorination or saturation of unsaturated bond may thus possibly serve as a regeneration system for a reduced coenzyme, which may be formed in an oxidation pathway of such compounds to acetate.