Estimation of Partition Coefficients of Fe-S Protein Models： Se Substitutions in Fe4S4Cysn

作     者：Francisco Torrens Gloria Castellano 

作者机构：Institute for Molecular Science University of Valencia Valencia 46071 Spain Faculty of Veterinary and Experimental Sciences Catholic University of Valencia Saint Vincent-Martyr Valencia 46001 Spain 

出 版 物：《Journal of Chemistry and Chemical Engineering》 (化学与化工（英文版）)

年 卷 期：2012年第6卷第10期

页      面：867-877页

学科分类：083001[工学-环境科学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 070301[理学-无机化学] 

主　　题：Solvation parameter model partition coefficient hydrophobic moment iron-sulphur protein mixed-valence non-integeroxidation number. 

摘      要：The SCAP method allows a semiquantitative estimation of the partitioning of many solutes between numerous pairs of solvents. The organic solvent-water partition coefficients P are calculated. For FeaS4Cysn, the organic solvent-water partition coefficients for l-octanol Po, cyclohexane Pch and chloroform Pcf decay 4.46, 6.25 and 4.60 log units per Cys, respectively. The Po is of the same order of magnitude as CDHI （conformationally dependent hydrophobic index） calculations and Pch-cf as computations performed with a method by Leo and Hansch. The logPo-ch-cf mean relative errors are 17%, 25% and-17%, which represent mean and unsigned relative errors of -3% and 20%. On varying the number of Cys, the structures show hydrophobic moments indicative of amphipathic compounds. For Se substitutions in Fe4SeaCys,, Po-ch-cf drop 4.52, 6.30 and 4.66 exponents per Cys. With the reference calculations, Po-ch-cf decay 4.03, 4.80 and 5.76 exponents per Cys. For FeaS4 mSemCys4, the calculated similar partition coefficients and hydrophobic moments, and lower distance in dendrogram suggest a role of Fe-Se clusters in physiological processes. The analysis is extended to lysozyme and its secondary structures.