摘要
Site-directed mutagenesis was used to obtain seven variants of tryptic fragment of bovine liver cytochrome bs (cyt bs), in which the negatively charged residues around the heme exposed edge of cyt bs were replaced by hydropho-bic amino acid alanine. Double-site mutants, triple-site mutants and even quadruple-site mutants were obtained. DNA sequencing and molecular weight measurements of the mutant proteins both confirmed that these site-directed muta-genesises were successfully performed. Spectroelectrochem-istry of these mutant proteins revealed that the apparent redox potentials of these mutant proteins caused a positive shift of 2-10 mV. The global structure of these mutant proteins did not show much difference from that of the wild type cyt bs, providing a solid base for the further study on the roles of the proteins’ surface charges.
Site-directed mutagenesis was used to obtain seven variants of tryptic fragment of bovine liver cytochrome bs (cyt bs), in which the negatively charged residues around the heme exposed edge of cyt bs were replaced by hydropho-bic amino acid alanine. Double-site mutants, triple-site mutants and even quadruple-site mutants were obtained. DNA sequencing and molecular weight measurements of the mutant proteins both confirmed that these site-directed muta-genesises were successfully performed. Spectroelectrochem-istry of these mutant proteins revealed that the apparent redox potentials of these mutant proteins caused a positive shift of 2-10 mV. The global structure of these mutant proteins did not show much difference from that of the wild type cyt bs, providing a solid base for the further study on the roles of the proteins' surface charges.
作者
WANG Yunhua, WANG Wenhu, LU Junxia, REN Yi, GU Shaohua, XIE Yi & HUANG Zhongxian1. Chemical Biology Lab, Department of Chemistry, Fudan University, Shanghai 200433, China
2. Genetic Institute, School of Life, Fudan University, Shanghai 200433, China
基金
the National Natural Science Foundation of China (Grant No. 29731030).