Reactivity of peroxidase and other biopolymers. Pulse radiolysis study of biopolymers

✍ Scribed by Hayashi, Koichiro ;Kobayashi, Kazuo

• Publisher: Wiley (John Wiley & Sons)
• Year: 1985
• Weight: 296 KB
• Volume: 12
• Category: Article
• ISSN: 0025-116X
• DOI: 10.1002/macp.1985.020121985119

✦ Synopsis

By virtue of its ability to generate hydrated electron and various radicals as reductants, the pulse radiolysis technique has been employed for investigating the mechanism of action for biopolylners.

The reduction of cytochrome oxidase by l-methylnicotinamide radical was investigated. A decrease of the 830 nm band was detected due to the reduction of "visible" copper. The rate of this fast process d e e s on the enzyme concentration. After the first phase of the reduction of copper, the return on the 830 nm band corresponding to oxidation of copper was observed. Concomitantly, the absorption at 605 and 4 4 5 nm due to the reduction of heme 5 increased, and their rate constants didn't depend on the enzyme concentration (1.8 x 1 0 4 s -' 1. nicotinamide radical reacts with the "visible" copper and subsequently flows to heme 5 by intramolecular migration.