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PubMed · 2855978

Comparative study of two trehalases from Candida utilis.

J C Argüelles·M Gacto
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Abstract

Candida utilis ATCC 60459 contains two intracellular trehalase enzymes clearly distinguishable by molecular weight, behaviour in ion-exchange chromatography and kinetic properties. The high molecular weight trehalase (500 kDa trehalase) is specifically inhibited by acetate and accounts for less than 30% of the total trehalase activity found in cell extracts. The smaller trehalase (280 kDa trehalase) exists mostly as a cryptic enzyme whose activity can be postranslationally activated by cAMP-dependent phosphorylation. The enzyme activity of the 280 kDa trehalase is strongly inhibited by Zn2+ and markedly enhanced in the presence of Ca2+ and Mn2+. The activation by these cations, contrariwise to that induced by ATP and cAMP, does not imply a covalent modification of the 280 kDa enzyme. Several parameters have been determined for both enzymes. The 280 kDa enzyme has the properties shown by the so-called regulatory trehalases whereas the 500 kDa enzyme presents characteristics of a nonregulatory type of trehalase.

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Adenosine TriphosphateCandidaCationsChromatography, Ion ExchangeCyclic AMPEnzyme ActivationFungal ProteinsIsoenzymesKineticsMolecular WeightPhosphorylationProtein KinasesProtein Processing, Post-TranslationalTrehalaseComparative StudyJournal Article

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J C Argüelles, M Gacto. 1986. Comparative study of two trehalases from Candida utilis.. https://pubmed.ncbi.nlm.nih.gov/2855978/

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