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PubMed · 41533

[5'-methylthioadenosine phosphorylase from Caldariella acidophila. 1. Purification and partial characterization].

A Oliva·M Cartenì-Farina·G Napolitano·G Romeo·V Zappia·M De Rosa·A Gambacorta
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Abstract

5'-Methylthioadenosine phosphorylase has been isolated from C.acidophila, a thermophilic bacterium living in acid hot springs at temperatures ranging from 63 to 89 degrees C. The enzyme has been purified to homogeneity in 32% yield. The enzyme shows a high degree of thermophilicity, its temperature optimum being 93 degrees C in the in vitro assay. The enzyme is exceptionally stable; no loss of activity was observable after exposure for 1 h at 100 degrees C. The optimum pH is about 7,2, with one-half of the maximal activity occurring at pH 6 and 9. The apparent Km for the substrates are: 8,3 x 10(-5) M for MTA and 4,3 x 10(-4) M for phosphate ions.

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AdenosineBacteriaChemical PrecipitationHot TemperatureHydrogen-Ion ConcentrationIndicators and ReagentsKineticsPentosyltransferasesPurine-Nucleoside PhosphorylaseThionucleosidesJournal Article

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A Oliva, M Cartenì-Farina, G Napolitano, G Romeo, V Zappia, M De Rosa, A Gambacorta. 1978-12-15. [5'-methylthioadenosine phosphorylase from Caldariella acidophila. 1. Purification and partial characterization].. https://pubmed.ncbi.nlm.nih.gov/41533/

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