Properties of catalase activities have been examined in the intact cells of early stationary phase and cells 3 hr after transfer to sporulation medium in Saccharomyces cerevisiae. The catalase activities of the two cells had a broad optimal pH from 6 to 8. Catalase activity in the intact cells incre
Trehalases from spores and vegetative cells of yeast Saccharomyces cerevisiae
β Scribed by Dr. Barbara Wolska-Mitaszko
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 636 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0233-111X
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β¦ Synopsis
Abstract
Trehalase (THA) activity from S. cerevisiae spores and vegetative cells could be differentiated in cellβfree extracts. THA from the vegetative cells has an optimal activity at neutral pH whereas biphase pH optimum in the spores was observed. The enzyme from the spores exhibited higher thermostability than that from the vegetative cells. The presence of magnesium ions was necessary mainly for THA activity from the vegetative cells. The effect of the other metal ions studied: Hg^2+^, Ag^2+^, Cu^2+^, Fe^3+^, Ni^2+^, Cd^2+^ etc. (Table II), on THA from both sources was almost the same, however, the spores THA was resistant to Pb^2+^ and especially to Zn^2+^. Moreover, the influence of inorganic polyphosphates and polyamines was also quite dissimilar. Polyphosphates inhibited THA from the vegetative cells and to a smaller extent from the spores. On the other hand, polyamines stimulated highly THA activity from vegetative yeast cells in contrast to spores one. The effect of these ions modulators would facilitate differentiating of THA activity in the cellβfree extracts from both sources. These data could be interpreted as phenotypic reflections of trehalase genes expression in the S. cerevisiae cells.
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