Substitutions of proline 76 in yeast iso-1-cytochrome c: analysis of residues compatible and incompatible with folding requirements

Journal Article · Fri Oct 25 04:00:00 EDT 1985 · J. Biol. Chem.; (United States)

OSTI ID:6297561

Ernst, J F; Hampsey, D M; Stewart, J W; Rackovsky, S; Goldstein, D; Sherman, F

Fine-structure genetic mapping previously revealed numerous nonfunctional cyc1 mutations having alterations at or near the site corresponding to amino acid position 76 of iso-1-cytochrome c from the yeast Saccharomyces cerevisiae. DNA sequencing of the alterations in four of these cyc1 mutations indicated that the normal Pro-76 was replaced by Leu-76. Revertants containing at least partially functional iso-1-cytochromes c were isolated, and the alterations were analyzed by DNA sequencing and protein analysis. Specific activities of the altered iso-1-cytochromes c were estimated in vivo by growth of the strains in lactate medium; compared to normal iso-1-cytochrome c with Pro-76, the following activities were associated with the following replacements: approx.90% for Val-76, approx.60% for Thr-76, approx.30% for Ser-76, approx.20% for Ile-76, and 0% for Leu-76. In order to develop an understanding of the factors that determine whether or not an altered iso-1-cytochrome c will function, the authors undertook a theoretical analysis which led to the conclusion that the activity of the proteins was dependent on both short- and long-range interactions. Short-range interactions were estimated from studies on known protein structures which gave the likelihood that various amino acids would be found in a local backbone configuration similar to the native protein; long-range interaction with the rest of the molecule were analyzed by considering the size of the side chain. The authors believe this approach can be used to analyze a wide variety of mutant proteins. 43 references, 9 figures, 4 tables.

• Research Organization: Univ. of Rochester, NY
• DOE Contract Number: AC02-76EV03490
• OSTI ID: 6297561
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 260:24; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550400* -- Genetics
59 BASIC BIOLOGICAL SCIENCES
AMINES
AMINO ACIDS
AZOLES
CARBOXYLIC ACIDS
CYTOCHROMES
DATA
DNA SEQUENCING
EXPERIMENTAL DATA
FUNGI
GENETIC MAPPING
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INFORMATION
MAPPING
MICROORGANISMS
MUTANTS
MUTATIONS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PIGMENTS
PLANTS
PROLINE
PROTEINS
PYRROLES
PYRROLIDINES
RESIDUES
REVERTANTS
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
STRUCTURAL CHEMICAL ANALYSIS
STRUCTURE-ACTIVITY RELATIONSHIPS
YEASTS