Heme peroxidase-catalyzed iodination of human angiotensins and the effect of iodination on angiotensin converting enzyme activity.
The heme peroxidase-catalyzed iodination of human angiotensins I and II is described. It is observed that lactoperoxidase (LPO) can effectively and selectively iodinate the tyrosyl residues in angiotensin peptides. The thiourea/thiouracil-based peroxidase inhibitors effectively inhibit the iodination reactions, indicating that iodination is an enzymatic reaction and the mechanism of iodination is similar to that of peroxidase-catalyzed iodination of thyroglobulin. This study also shows that the monoiodo Ang I is a better substrate for the angiotensin converting enzyme than the native peptide.
Bhuyan
Bhaskar J
BJ
Department of Inorganic & Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India.
Mugesh
Govindasamy
G
D000363:Agaricales / Q000201:enzymology; D000803:Angiotensin I / Q000378:metabolism*; D000804:Angiotensin II / Q000378:metabolism*; D002384:Catalysis; D004791:Enzyme Inhibitors / Q000494:pharmacology; D054879:Halogenation; D006420:Hemeproteins / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D007784:Lactoperoxidase / Q000378:metabolism; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D009195:Peroxidase / Q000378:metabolism*
D004791:Enzyme Inhibitors; D006420:Hemeproteins; D000804:Angiotensin II; D000803:Angiotensin I; D007784:Lactoperoxidase; D009195:Peroxidase; D007703:Peptidyl-Dipeptidase A