Identification and characterization of coenzyme B12-dependent glycerol dehydratase- and diol dehydratase-encoding genes from metagenomic DNA libraries derived from enrichment cultures.

ABSTRACT: To isolate genes encoding coenzyme B(12)-dependent glycerol and diol dehydratases, metagenomic libraries from three different environmental samples were constructed after allowing growth of the dehydratase-containing microorganisms present for 48 h with glycerol under anaerobic conditions. The libraries were searched for the targeted genes by an activity screen, which was based on complementation of a constructed dehydratase-negative Escherichia coli strain. In this way, two positive E. coli clones out of 560,000 tested clones were obtained. In addition, screening was performed by colony hybridization with dehydratase-specific DNA fragments as probes. The screening of 158,000 E. coli clones by this method yielded five positive clones. Two of the plasmids (pAK6 and pAK8) recovered from the

SUBMITTER: Knietsch A 

PROVIDER: S-EPMC161467 | biostudies-literature | 2003 Jun

REPOSITORIES: biostudies-literature