title: Kinetic studies on the oxidation of cytochrome b(5) Phe35 mutants with cytochrome c, plastocyanin and inorganic complexes.
abstract: To illustrate the functions of the aromatic residue Phe35 of cytochrome b(5) and to give further insight into the roles of the Phe35-containing hydrophobic patch and/or aromatic channel of cytochrome b(5), we studied electron transfer reactions of cytochrome b(5) and its Phe35Tyr and Phe35Leu variants with cytochrome c, with the wild-type and Tyr83Phe and Tyr83Leu variants of plastocyanin, and with the inorganic complexes [Fe(EDTA)](-), [Fe(CDTA)](-) and [Ru(NH(3))(6)](3+). The changes at Phe35 of cytochrome b(5) and Tyr83 of plastocyanin do not affect the second-order rate constants for the electron transfer reactions. These results show that the invariant aromatic residues and aromatic patch/channel are not essential for electron transfer in these systems.
authors.affiliation: Chemical Biology Laboratory, Department of Chemistry, Fudan University, Shanghai 200433, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yao
authors.forename: Yun-Hua
authors.initials: YH
authors.lastname: Wang
authors.forename: Bing-Yun
authors.initials: BY
authors.lastname: Sun
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
authors.forename: Shun
authors.initials: S
authors.lastname: Hirota
authors.forename: Osamu
authors.initials: O
authors.lastname: Yamauchi
authors.forename: Zhong-Xian
authors.initials: ZX
authors.lastname: Huang
mesh_terms: D003574:Cytochrome c Group / Q000378:metabolism*; D015786:Cytochromes b5 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004492:Edetic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D004579:Electron Transport; D007287:Inorganic Chemicals / Q000737:chemistry / Q000378:metabolism; D007501:Iron / Q000737:chemistry; D007700:Kinetics; D007930:Leucine / Q000235:genetics; D009154:Mutation; D010084:Oxidation-Reduction; D010649:Phenylalanine / Q000235:genetics; D010970:Plastocyanin / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D014443:Tyrosine / Q000235:genetics
chemical_list: D003574:Cytochrome c Group; D007287:Inorganic Chemicals; D014443:Tyrosine; D010649:Phenylalanine; C005390:CDTA; D010970:Plastocyanin; D015786:Cytochromes b5; D004492:Edetic Acid; D007501:Iron; D007930:Leucine