Clustering of genes necessary for hydrogen oxidation in Rhodobacter capsulatus

Three cosmids previously shown to contain information necessary for the expression of uptake of hydrogenase in Rhodobacter capsulatus were found to be present in a cluster on the chromosome. Earlier genetic experiments suggested the presence of at least six genes essential for hydrogenase activity that are now shown to be in a region of approximately 18 kb that includes the structural genes for the enzyme. A potential response regulator gene was sequenced as a part of the hup gene region.