Isolation of uroporphyrinogen III synthase from Escherichia coli

Biosynthesis of the pigments of life: mechanistic studies on the conversion of porphobilinogen to uroporphyrinogen III

“…Therefore, it is only recently that cosynthetase has been purified to a high degree, from rat liver,71 E. gracilis,72 and E. coli. 73 The gene for cosynthetase (hemD) in E. coli was found immediately following that of deaminase (hemC); in fact, the first base pair of the former is the last one of the latter. Both this gene49,74 and the corresponding aM« human one75 have recently been sequenced, and the E. coli enzyme has been overexpressed up to 1000-fold, which has allowed the isolation of milligram quantities for the first time.76 Following the genes for deaminase and cosynthetase on the genome of E. coli are two further genes that appear to be part of the same operon (i.e., their transcription is controlled by the same promoter).…”