- 作者: 陳水田 ; 王光燦
- 作者服務機構: 中央研究院生物化學研究所
- 中文摘要: Internal electron transfer in bovine cytochrome c oxidase was initiated by CO photolysis of the CO-bound mixed-valence form of the enzyme. Transient absorption spectroscopy was used to monitor changes in the redox states of the metal centers in the enzyme brought about by electron re-equilibration. Upon CO photodissociation, reduced high spin cytochrome a/sub 3/ was generated in less than 0.1 .mu..sec, and a portion of the reduced cytochrome a/sub 3/ was reoxidized with biphasic rate constants of k/sub 1/=1.0 * 10/sup 6/ s/sup -1/ and k/sub 2/=7.8 * 10/sup 4/ s/sup -1/. Concomitant reduction of cytochrome a was also observed with biphasic rate constants of k/sub 1/ = 1.6 * 10/sup 6/ s /sup -1/and k/sub 2/ = 9 * 10/sup 4/ s/sup-1/. The stoichiometry of cytochrome a/sub 3/ oxidized to cytochrome a reduced was found to be close to 1:1. Contrary to similar studies in the literature, no reduction of Cu/sub A/ was observed. As a control, no transient absorption changes corresponding to electron transfer was observed in the CO- inhibited fully reduced form of the enzyme. These results indicate that there is significant electron reequilibration only between cytochrome a/sub 3/ and cytochrome a upon photolysis of the CO-bound mixed- valence enzyme.
- 英文摘要: --
- 中文關鍵字: Alcalase; Alkline Protease; Amino Acid; Peptide; Enzyme Production
- 英文關鍵字: 鹼蛋白酵素;鹼性蛋白;胺基酸;胜;生產