A membrane-bound pyrophosphatase from respiratory membranes of Rhodospirillum rubrum

Autor: Heliodoro Celis, Alberto Gómez-Priego, Irma Romero
Rok vydání: 1991
Předmět:
Zdroj: Journal of General Microbiology. 137:2611-2616
ISSN: 0022-1287
DOI: 10.1099/00221287-137-11-2611
Popis: Summary: A pyrophosphatase activity was found in respiratory membranes of Rhodospirillum rubrum. This activity was specific for pyrophosphate and was inhibited by dicyclohexylcarbodiimide, NaF and pyrophosphate analogues, but not by oligomycin or LiCl. The divalent cation selectivity was Zn2+ > Mg2+ > Co2+ > Ca2+, and the pH dependence was the same as that of the membrane-bound pyrophosphatase of chromatophores (optimum pH 6·5). The pyrophosphate hydrolysis activity of respiratory membranes was inhibited by 1-butanol. The enzyme was solubilized by Triton X-100, and the activity of the solubilized enzyme was stimulated by phospholipids. The respiratory-membrane enzyme ran in native electrophoresis with the same R F as the membrane-bound pyrophosphatase of chromatophores. Antibodies raised against both enzymes cross-reacted with each other. These findings show that a membrane-bound pyrophosphatase is present in respiratory membranes of R. rubrum and is similar to the enzyme of photosynthetic membranes.
Databáze: OpenAIRE