Wuhan University Journal of Natural Sciences

, Volume 12, Issue 6, pp 1029–1033 | Cite as

Effect of residue mutation on the electrostatic potential in EcCIC

  • Zou Xianwu 
  • Dong Shuxiang 
  • Wang Xiaoqing 
  • Huang Shengyou 


The effect of mutation of strongly conserved porelining residues in the chloride channel EcClC on the electrostatic potential and binding free energy of the chloride ion was studied using explicit protein-membrane structures. Electrostatic potential distribution and binding free energy of the chloride ion at different binding sites in the wild-type and mutated EcClC were calculated with APBS. The potential data reveal that the electrostatic potential around the selectivity filter, especially around the site S ext and S cen becomes more negative as the residue R147 was mutated to C147. The electrostatic binding free energy shows that the binding free energy of the chloride ion at all binding sites becomes more positive as R147 was mutated. It follows that mutation of R147 decreases ion stabilization at binding sites and affects channel’s gating.

Key words

chloride channel electrostatic potential binding free energy mutation 

CLC number

O 469 Q 615 


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Copyright information

© Wuhan University 2007

Authors and Affiliations

  • Zou Xianwu 
    • 1
  • Dong Shuxiang 
    • 1
  • Wang Xiaoqing 
    • 1
  • Huang Shengyou 
    • 1
  1. 1.School of Physics and TechnologyWuhan UniversityWuhanChina

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