Influence of Vitamin B 12 and Cocultures on the Growth of Dehalococcoides Isolates in Defined Medium

• DOI: 10.1128/aem.02574-06
• Publication Date: 2007-03-03T02:13:21Z
• Authors: Jianzhong He; Victor F. Holmes; Patrick K. H. Lee; Lisa Alvarez-Cohen
• Keywords: Dehalococcoides; Reductive Dechlorination; Strain (injury); Growth medium

Bacteria belonging to the genus Dehalococcoides play a key role in complete detoxification of chloroethenes as these organisms are only microbes known be capable dechlorination beyond dichloroethenes vinyl chloride (VC) and ethene. However, strains usually grow slowly with doubling time 1 2 days have complex nutritional requirements. Here we describe growth ethenogenes 195 defined mineral salts medium, improved strain when medium was amended high concentrations vitamin B(12), strategy for maintaining on lactate by growing them consortia. Although could spiked approximately 0.5 mM trichloroethene (TCE) 0.001 mg/liter TCE cellular rates doubled B(12) concentration increased 25-fold 0.025 mg/liter. In addition, final ratios ethene VC higher used, which reflected that cobalamin plays reactions. No further improvement or observed more than consortia containing along Desulfovibrio desulfuricans and/or Acetobacterium woodii electron donor, tetrachloroethene ( 0.4 mM) completely dechlorinated there concomitant cells. cultures also contained D. A. woodii, cells grew densities were 1.5 times greater obtained isolate grown alone. The ratio highest presence an organism generates de novo during metabolism. These findings demonstrate can optimized providing this cocultures fermenters convert generate required hydrogen acetate may enhance availability B(12).