Study of the biological significance of cytochrome methylation I. Thermal, acid and guanidinium hydrochloride denaturations of baker's yeast ferricytochromes c

Probing Stability and Dynamics of Proteins by Protease Digestion I: Comparison of Protease Susceptibility and Thermal Stability of Cytochromes c

“…We found only a weak correlation of the protease susceptibility with another type of overall stability reflected in the GuHCl denaturation whose stability order for cytochromes c has been reported (25)(26)(27); for example, tuna cytochrome c was more stable than mammalian (27). The denaturation state of cytochrome c in 6 M GuHCl, where CD 222 is near zero (18), is different from that of thermal denaturation where the value of CD 222 is half that in the native state.…”

Evidence that trimethylation of iso‐I‐cytochrome c from Saccharomyces cerevisiae affects interaction with the mitochondrion

“…In investigations comparing the methylated and Address correspondence to: E. T. Polastro unmethylated forms of iso-Icytochrome c from baker's yeast, we have shown that methylation of lysine 72 does not affect the conformation [7] or the stability towards denaturation by different agents [8]. The two forms showed the same redox potentials, autooxidation parameters and capacity to serve as substrates to cytochrome c oxidase, cytochrome c peroxidase and succinate cytochrome c oxidoreductase [9].…”

Refolding a disulfide dimer of cytochrome c

“…Analysis of the pH dependence of these absorbance changes as illustrated in Figure 2 indicates that the acid spin-state transition of each form of the protein involves 1.1 ± 0.1 protons having a pK value of 3.2 ± 0.1. Polastro et al (1976) have previously reported a pK value of 3.3 for the monomeric protein.…”