Apparent cytochrome gene dose effects in F-lac and F-gal heterogenotes of Escherichia coli.
Abstract
The levels of b- and c-type cytochromes and cytochromes a1 and a2 are elevated in a partial diploid strain of E. coli carrying the F2-gal episome under a variety of different growth conditions. Only the levels of b- and c-type cytochromes were significantly increased in three F-lac partial diploids, and no increase was observed in an F3-gal partial diploid. The results suggest that a number of cytochrome genes are clustered in a 2-min long region of the chromosome between purEand the vicinity of supE.