In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium
Our objective was to characterize the modulation of the activity of Saccharomyces cerevisiae alkaline phosphatases (ALPs) by classic inhibitors of ALP activity, cholesterol and steroid hormones, in order to identify catalytic similarities between yeast and mammalian ALPs. S. cerevisiae expresses two...
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| Format: | Article |
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Associação Brasileira de Divulgação Científica
2008-01-01
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| Series: | Brazilian Journal of Medical and Biological Research |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008000100007 |
| _version_ | 1819199305986080768 |
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| author | J Fernandes R Amorim I Azevedo M.J Martins |
| author_facet | J Fernandes R Amorim I Azevedo M.J Martins |
| author_sort | J Fernandes |
| collection | DOAJ |
| description | Our objective was to characterize the modulation of the activity of Saccharomyces cerevisiae alkaline phosphatases (ALPs) by classic inhibitors of ALP activity, cholesterol and steroid hormones, in order to identify catalytic similarities between yeast and mammalian ALPs. S. cerevisiae expresses two ALPs, coded for by the PHO8 and PHO13 genes. The product of the PHO8 gene is repressible by Pi in the medium. ALP activity from yeast (grown in low or high phosphate medium) homogenates was determined with p-nitrophenylphosphate as substrate, pH 10.4 (lPiALP or hPiALP, respectively). Activation of hPiALP was observed with 5 mM L-amino acids (L-homoarginine _ 186%, L-leucine _ 155% and L-phenylalanine - 168%) and with 1 mM levamisole (122%; percentage values, in comparison to control, of recovered activity). EDTA (5 mM) and vanadate (1 mM) distinctly inhibited hPiALP (2 and 20%, respectively). L-homoarginine (5 mM) had a lower activating effect on lPiALP (166%) and was the strongest hPiALP activator. Corticosterone (5 mM) inhibited hPiALP to 90%, but no effect was observed in low phosphate medium. Cholesterol, ß-estradiol and progesterone also had different effects on lPiALP and hPiALP. A concentration-dependent activation of lPiALP minus hPiALP was evident with all three compounds, most especially with ß-estradiol and cholesterol. These results do not allow us to identify similarities of the behavior of S. cerevisiae ALPs and any of the mammalian ALPs but allow us to raise the hypothesis of differential regulation of S. cerevisiae ALPs by L-homoarginine, ß-estradiol and cholesterol and of using these compounds to discriminate between S. cerevisiae lPiALP and hPiALP. |
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| institution | Directory Open Access Journal |
| issn | 0100-879X 1414-431X |
| language | English |
| last_indexed | 2024-12-23T03:14:14Z |
| publishDate | 2008-01-01 |
| publisher | Associação Brasileira de Divulgação Científica |
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| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-ea01a12d4dfc4bbcae7879b2af04429a2022-12-21T18:02:12ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research0100-879X1414-431X2008-01-014114146In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate mediumJ FernandesR AmorimI AzevedoM.J MartinsOur objective was to characterize the modulation of the activity of Saccharomyces cerevisiae alkaline phosphatases (ALPs) by classic inhibitors of ALP activity, cholesterol and steroid hormones, in order to identify catalytic similarities between yeast and mammalian ALPs. S. cerevisiae expresses two ALPs, coded for by the PHO8 and PHO13 genes. The product of the PHO8 gene is repressible by Pi in the medium. ALP activity from yeast (grown in low or high phosphate medium) homogenates was determined with p-nitrophenylphosphate as substrate, pH 10.4 (lPiALP or hPiALP, respectively). Activation of hPiALP was observed with 5 mM L-amino acids (L-homoarginine _ 186%, L-leucine _ 155% and L-phenylalanine - 168%) and with 1 mM levamisole (122%; percentage values, in comparison to control, of recovered activity). EDTA (5 mM) and vanadate (1 mM) distinctly inhibited hPiALP (2 and 20%, respectively). L-homoarginine (5 mM) had a lower activating effect on lPiALP (166%) and was the strongest hPiALP activator. Corticosterone (5 mM) inhibited hPiALP to 90%, but no effect was observed in low phosphate medium. Cholesterol, ß-estradiol and progesterone also had different effects on lPiALP and hPiALP. A concentration-dependent activation of lPiALP minus hPiALP was evident with all three compounds, most especially with ß-estradiol and cholesterol. These results do not allow us to identify similarities of the behavior of S. cerevisiae ALPs and any of the mammalian ALPs but allow us to raise the hypothesis of differential regulation of S. cerevisiae ALPs by L-homoarginine, ß-estradiol and cholesterol and of using these compounds to discriminate between S. cerevisiae lPiALP and hPiALP.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008000100007Saccharomyces cerevisiaeAlkaline phosphatase inhibitorsPHO8 and PHO13CholesterolSteroid hormones |
| spellingShingle | J Fernandes R Amorim I Azevedo M.J Martins In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium Brazilian Journal of Medical and Biological Research Saccharomyces cerevisiae Alkaline phosphatase inhibitors PHO8 and PHO13 Cholesterol Steroid hormones |
| title | In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium |
| title_full | In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium |
| title_fullStr | In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium |
| title_full_unstemmed | In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium |
| title_short | In vitro modulation of alkaline phosphatase activity of Saccharomyces cerevisiae grown in low or high phosphate medium |
| title_sort | in vitro modulation of alkaline phosphatase activity of saccharomyces cerevisiae grown in low or high phosphate medium |
| topic | Saccharomyces cerevisiae Alkaline phosphatase inhibitors PHO8 and PHO13 Cholesterol Steroid hormones |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008000100007 |
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