Abstract
A genetic analysis of a 12-kb DNA fragment containing Pseudomonas denitrificans cob genes was performed by transposon-mediated insertional mutagenesis. The nucleotide sequence and genetic analysis have shown that a 4.8-kb DNA subfragment carried two cob genes (cobS and cobT). Biochemical data concerning the complemented cobS and cobT mutants suggested that the cobS product was involved in cobalt insertion-mediating reactions and that the cobT product was involved in the transformation of precorrin-3 into cobyrinic acid.