RESUMO
A 30 kd hydrophobic protein is extracted from yeast mitochondrial inner membrane. It is present in wild yeast strains but absent in mitochondrial DNA lacking mutants. The isoelectric point of the protein and its solubility in various organic solvents are determined. The fluorescence of a tryptophan residue near the surface of the 30 kd protein dissolved in butanol-1, can be quenched by phospholipids containing unsaturated fatty acids. Results are in accordance with the 30 kd protein being an integral protein of the yeast mitochondrial inner membrane.
Assuntos
Membranas Intracelulares/análise , Proteínas de Membrana/isolamento & purificação , Mitocôndrias/análise , Fosfolipídeos/farmacologia , Saccharomyces cerevisiae/análise , Eletroforese em Gel de Poliacrilamida , Proteínas de Membrana/metabolismo , Peso Molecular , Solubilidade , Relação Estrutura-AtividadeRESUMO
A yeast mitochondrial inner membrane hydrophobic protein 30K has been isolated and compared to subunit 32K of the yeast cytochrome bc 1 complex. Both proteins are translated on mitochondrial ribosomes, have nearly the same molecular weight and similar aminoacid compositions. Comparison was carried out by immunological techniques with specific antibodies, and by studying 3 yeast strains having mutations in the COB region of the mitochondrial DNA. Results show that the two proteins are not identical.