Effects of salts of alkali earth metals and calcium chloride on the stability of cytochrome c and myoglobin.


Abstract

This study suggests a procedure by which binding of denaturants could be detected without any additional information other than that provided in the denaturation profiles of proteins. Two predominantly alpha-proteins, namely ferricytochrome c and metmyoglobin were denatured by guanidine hydrochloride (GdnHCl) in the presence of low fixed concentrations of salts at 25 degrees C and transition between native and denatured states was followed by absorbance measurements in the visible region (500-350 nm). The raw data were converted into transition curves from which Cm, the midpoint of GdnHCl-induced transition, and deltaGapp, the free energy changes on denaturation, were calculated assuming a two-state mechanism, and values of deltaGapp at zero concentration of the denaturant were estimated. It has been observed (1) that chlorides of Na, K, Cs, and Rb do not affect the native conformation of proteins, (2) that GdnHCl-induced denaturations of proteins in presence and absence of sodium bromide, sodium perchlorate and salts of lithium and calcium are reversible, (3) that optical properties of the GdnHCl-denatured state of proteins remain unchanged in presence of the second denaturant, (4) Cm decreases with an increase in the denaturant concentration, and (5) that except for GdnHCl there exist one or more binding sites on the native proteins for the denaturants. Study holds ProTherm entries: 10028, 10029 Extra Details: binding of denaturants;free changes on denaturation;,two-state mechanism;binding sites

Submission Details

ID: f3iFd2QK3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:39 p.m.

Version: 1

Publication Details
Ahmad Z;Yadav S;Ahmad F;Khan NZ,Biochim. Biophys. Acta (1996) Effects of salts of alkali earth metals and calcium chloride on the stability of cytochrome c and myoglobin. PMID:8639715
Additional Information

Sequence Assay Result Units