Enzymatic synthesis of dihydrosirohydrochlorin (precorrin-2) and of a novel pyrrocorphin by uroporphyrinogen III methylase.
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.
Department of Chemistry, Texas A & M University, College Station 77843.
M J
MJ
Warren
N J
NJ
Stolowich
P J
PJ
Santander
C A
CA
Roessner
B A
BA
Sowa
A I
AI
Scott
D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D004926:Escherichia coli / Q000201:enzymology*; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011166:Porphyrins / Q000096:biosynthesis*; D013053:Spectrophotometry; D014578:Uroporphyrins / Q000096:biosynthesis*; D014805:Vitamin B 12 / Q000096:biosynthesis
D011166:Porphyrins; D014578:Uroporphyrins; C063209:15,23-dihydrosirohydrochlorin; D008780:Methyltransferases; C060508:uroporphyrin-III C-methyltransferase; D014805:Vitamin B 12