Terui Norifumi, Tachiiri Naoki, Matsuo Hitomi, Hasegawa Jun, Uchiyama Susumu, Kobayashi Yuji, Igarashi Yasuo, Sambongi Yoshihiro, Yamamoto Yasuhiko
Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan.
J Am Chem Soc. 2003 Nov 12;125(45):13650-1. doi: 10.1021/ja035682f.
Electrochemical, 1H NMR, and optical studies on mesophile Pseudomonas aeruginosa cytochrome c551, its single (F34Y) and quintuple (F7A/V13M/F34Y/E43Y/V78I) mutants, and thermophile Hydrogenobacter thermophilus cytochrome c552 at wide temperature range demonstrated that the stable protein exhibits the low redox potential predominantly due to the enthalpic contribution to the redox reaction. The overall stability of the oxidized form was shown to determine the stability of the Fe-methionine coordination bond, which then directly regulates the redox function.
对嗜温性铜绿假单胞菌细胞色素c551、其单突变体(F34Y)和五重突变体(F7A/V13M/F34Y/E43Y/V78I)以及嗜热性嗜氢栖热菌细胞色素c552在宽温度范围内进行的电化学、1H核磁共振和光学研究表明,这种稳定的蛋白质呈现低氧化还原电位主要归因于氧化还原反应的焓贡献。结果显示,氧化形式的整体稳定性决定了铁-甲硫氨酸配位键的稳定性,进而直接调节氧化还原功能。