Journal of Bioenergetics and Biomembranes

, Volume 41, Issue 3, pp 251–257

Evolutionary alkaline transition in human cytochrome c

  • Tianlei Ying
  • Fangfang Zhong
  • Jin Xie
  • Yanjiao Feng
  • Zhong-Hua Wang
  • Zhong-Xian Huang
  • Xiangshi Tan
Article

DOI: 10.1007/s10863-009-9223-9

Cite this article as:
Ying, T., Zhong, F., Xie, J. et al. J Bioenerg Biomembr (2009) 41: 251. doi:10.1007/s10863-009-9223-9

Abstract

Conformational transitions in cytochrome c (cyt c) are being realized to be responsible for its multi-functions. Among a number of conformational transitions in cyt c, the alkaline transition has attracted much attention. The cDNA of human cyt c is cloned by RT-PCR and a high-effective expression system for human cyt c has been developed in this study. The equilibrium and kinetics of the alkaline transition of human cyt c have been systematically investigated for the first time, and compared with those of yeast and horse cyt c from an evolutionary perspective. The pKa value for the alkaline transition of human cyt c is apparently higher than that of yeast and horse. Kinetic studies suggest that it is increasingly difficult for the alkaline transition of cyt c from yeast, horse and human. Molecular modeling of human cyt c shows that the omega loop where the lysine residue is located apparently further away from heme in human cyt c than in yeast iso-1 and horse heart cyt c. These results regarding alkaline conformational transition provide valuable information for understanding the molecular basis for the biological multi-functions of cyt c.

Keywords

Human cytochrome cAlkaline transitionpH-jump

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Tianlei Ying
    • 1
  • Fangfang Zhong
    • 1
  • Jin Xie
    • 1
  • Yanjiao Feng
    • 1
  • Zhong-Hua Wang
    • 1
  • Zhong-Xian Huang
    • 1
  • Xiangshi Tan
    • 1
  1. 1.Department of Chemistry & Institutes of Biomedical SciencesFudan UniversityShanghaiChina