Uroporphyrin- and Coproporphyrin I-accumulating Mutant of Escherichia coli K12

Abstract
A new type of heme-deficient mutant was isolated in E. coli K12 by neomycin selection. The mutant was deficient in uroporphyrinogen III cosynthase activity as indicated by the accumulation of uroporphyrin I and coproporphyrin I. The mapping of the corresponding hemD gene by [phage] P1-mediated transduction showed that the new gene was located between ilv and cya, at min 83 on the chromosomal map of E. coli K12.