Enzymatic synthesis of dihydrosirohydrochlorin (precorrin-2) and of a novel pyrrocorphin by uroporphyrinogen III methylase

• Published in: FEBS letters Vol. 261; no. 1; pp. 76 - 80
• Main Authors: Warren, Martin J., Stolowich, Neal J., Santander, Patricio J., Roessner, Charles A., Sowa, Blair A., Scott, A.Ian
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 12.02.1990; Elsevier
• Subjects: Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Chromatography, High Pressure Liquid; Dihydrosirohydrochlorin; Dipyrrocorphin; Escherichia coli - enzymology; Fundamental and applied biological sciences. Psychology; HPLC, high pressure liquid chromatography; Intermediary metabolites. Miscellaneous; Magnetic Resonance Spectroscopy; Methylation; Methyltransferases - metabolism; Molecular Sequence Data; Molecular Structure; NMR, 13C; NMR, nuclear magnetic resonance; Other biological molecules; pbg, porphobilinogen; Porphyrins - biosynthesis; Precorrin-2; Pyrrocorphin; SAM, S-adenosyl methionine; Spectrophotometry; SUMT, S-adenosyl methionine uroporphyrinogen methyl transferase; uro'gen, uroporphyrinogen; Uroporphyrinogen III methylase; Uroporphyrins - biosynthesis; Vitamin B 12 - biosynthesis; pbg, porphobilinogen; Dipyrrocorphin; SUMT, S-adenosyl methionine uroporphyrinogen methyl transferase; Pyrrocorphin; SAM, S-adenosyl methionine; NMR, nuclear magnetic resonance; Dihydrosirohydrochlorin; Uroporphyrinogen III methylase; uro'gen, uroporphyrinogen; HPLC, high pressure liquid chromatography; Precorrin-2; NMR, 13C; Enzyme; Escherichia coli; HPLC chromatography; Bacteria; Biosynthesis; NMR spectrometry; Enterobacteriaceae; Ultraviolet visible spectrometry
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(90)80640-5

Uroporphyrinogen III methylase was purified from a recombinant hemB − strain of E. coli harbouring a plasmid containing the cysG gene. N-terminal analysis of this purified protein gave an amino acid sequence corresponding to that predicted from the genetic code. From the u.v./visible spectrum of the reaction catalysed by this SAM dependent methylase it was possible to observe the sequential appearance of the chromophores of a dipyrrocorphin and subsequently of a pyrrocorphin. Confirmation of this transformation was obtained from 13C-NMR studies when it was demonstrated, for the first time directly, that uroporphyrinogen is initially converted into dihydrosirohydrochlorin (precorrin-2) and then, by further methylation, into a novel trimethylpyrrocorphin.