Biomaterial Database

Folding of yeast iso-1-AM cytochrome c. 1983

E H Zuniga, and B T Nall

We describe a specific modification of iso-1 cytochrome c which results in blocking a single free sulfhydryl group. The derivative differs from the unmodified protein by the introduction of a small, uncharged group, thus maintaining the same charge balance as the native protein. The modified protein, obtained by treatment of iso-1 cytochrome c with iodoacetamide, has an activity indistinguishable from that of the unmodified protein in the lactate dehydrogenase-cytochrome c reductase system from yeast and has the same stability toward denaturation by guanidine hydrochloride. The kinetics of fluorescence changes associated with the guanidine hydrochloride induced folding-unfolding transition for modified iso-1 cytochrome c (iso-1-AM) have been investigated throughout the transition zone by using stopped-flow mixing. The results are compared to those for the yeast isozyme, iso-2 cytochrome c. The main features of the fluorescence-detected folding kinetics are similar, as might be expected for homologous proteins; however, the limiting value of the fraction of fast refolding protein (alpha 2) below the transition zone is smaller for iso-1-AM (approximately 0.7) than for iso-2 (approximately 0.9).

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D002621	Chemistry	A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
D003574	Cytochrome c Group	A group of cytochromes with covalent thioether linkages between either or both of the vinyl side chains of protoheme and the protein. (Enzyme Nomenclature, 1992, p539)	Cytochromes Type c,Group, Cytochrome c,Type c, Cytochromes
D006146	Guanidines	A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D001345	Autoradiography	The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)	Radioautography
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013053	Spectrophotometry	The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.