Importance of a conserved phenylalanine-35 of cytochrome b5 to the protein's stability and redox potential.


Phenylalanine-35, which is a residue of the hydrophobic patch on the surface of cytochrome b5, has been mutated into Tyr35, His35 and Leu35 to elucidate the functions of the Phe35 and give further insight into the roles of the hydrophobic patch and/or aromatic network. The effects of these mutations on the heme environment, denaturation towards heating and the denaturant urea, redox potential and stability of protein were studied. The relative stability of cytochrome b5 and its mutants towards heating has the order Phe35Tyr > wild type > Phe35Leu > Phe35His in the oxidized state and wild type > Phe35Tyr > Phe35Leu > Phe35His in the reduced state. All the mutants exhibit decreased reduction potentials: Phe35Tyr -66 mV, Phe35His -51 mV and Phe35Leu -28 mV, which are more negative than that of the wild type. The order of redox potential reflects the relative stability in the oxidized and reduced states. A method of producing multiple mutants at a single site of a gene is also described for the first time. Study holds ProTherm entries: 3107, 3108, 3109, 3110, 3111, 3112, 3113, 14154, 14155, 14156 Extra Details: Ru(NH3)6Cl3 (0.01 mM) was added in the experiment cytochrome b5; phenylalanine; hydrophobic patch;,protein stability; redox potential

Submission Details

ID: 9Qn6RgsW

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:21 p.m.

Version: 1

Publication Details
Yao P;Xie Y;Wang YH;Sun YL;Huang ZX;Xiao GT;Wang SD,Protein Eng. (1997) Importance of a conserved phenylalanine-35 of cytochrome b5 to the protein's stability and redox potential. PMID:9215576
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Cytochrome b5 P00171 CYB5_BOVIN
96.7 Cytochrome b5 P00172 CYB5_PIG
91.3 Cytochrome b5 P00170 CYB5_HORSE
91.3 Cytochrome b5 P00169 CYB5_RABIT
90.2 Cytochrome b5 P00167 CYB5_HUMAN
91.3 Cytochrome b5 P00173 CYB5_RAT
90.2 Cytochrome b5 P56395 CYB5_MOUSE
92.9 Cytochrome b5 P00168 CYB5_ALOSE