Ethanolamine ammonia-lyase: Inactivation of the holoenzyme by N2O and the mechanism of action of coenzyme B12

✍ Scribed by G.N. Schrauzer; E.A. Stadlbauer

• Publisher: Elsevier Science
• Year: 1975
• Weight: 787 KB
• Volume: 4
• Category: Article
• ISSN: 0006-3061
• DOI: 10.1016/s0006-3061(00)80102-7

✦ Synopsis

Functional ethanolamine ammonia-lyase is inactivated by N1O as well as by 0 +, indicating that the active form of coenzyme B, Z is an enzyme-bound corrin derivative in which the Co-C bond of the coenzyme is broken and the cobalt ion is in the +l state of oxidation. The nucleoside fragment formed in the process of coenzyme activation is tentatively identified as 4',5'-didehydro-S-deoxyadenosine. A mechanism of action of ethanolamine ammonia-Iyase is formulated in analogy to that of DL-1,2-propanediol dehydrase and compared to proposed alternative reaction schemes.