Partial characterization of the steroidsulfatases in Peptococcus niger H4
Partial characterization of the steroidsulfatases in Peptococcus niger H4
复制标题
黑消化球菌 H4 中类固醇硫酸酯酶的部分表征
DOI：
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发表时间：
1991
影响因子：
4.4
通讯作者：
H. Eyssen
中科院分区：
文献类型：
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作者：
J. van Eldere;G. Parmentier;S. Asselberghs;H. Eyssen
严格厌氧的肠道黑消化尼日尔H4合成三种不同的类固醇硫酸酯酶：一种组成型芳基硫酸酯酶和两种诱导型烷基类固醇硫酸酯酶。芳基硫酸酯酶使雌激素-3-硫酸酯和苯硫酸酯水解。这两种烷基类固醇硫酸酯酶分别对δ 5、5 α和5 β雄甾烷、孕烷和胆汁酸的3 α-硫酸酯和3 β-硫酸酯进行酯化。胆固醇-3 β-硫酸酯不被烷基类固醇硫酸酯酶所取代，在3位以外的位置被硫酸化的类固醇或胆汁酸也不被烷基类固醇硫酸酯酶所取代。烷基类固醇硫酸酯酶由其底物诱导;然而，胆汁酸硫酸酯是3 β-硫酸酯酶的不良诱导剂，并且不诱导3 α-硫酸酯酶活性。在完整的细菌细胞中，牛磺酸和亚硫酸盐抑制烷基类固醇硫酸酯酶的诱导，并抑制芳基硫酸酯酶和烷基类固醇硫酸酯酶的活性。在细胞匀浆中，芳基硫酸酯酶和烷基类固醇硫酸酯酶的活性被抑制亚硫酸盐和硫酸盐，但不被牛磺酸。我们的研究结果支持这一假设，即在尼日尔H4的类固醇硫酸酯酶的主要功能是提供硫的细菌异化的目的。
The strictly anaerobic intestinal Peptococcus niger H4 synthesizes three different steroidsulfatase enzymes: a constitutive arylsulfatase and two inducible alkylsteroidsulfatases. The arylsulfatase desulfates estrogen-3-sulfates and phenylsulfates. The two alkylsteroidsulfatases desulfate, respectively, 3 alpha-sulfates and 3 beta-sulfates of delta 5, 5 alpha, and 5 beta androstanes, pregnanes, and bile acids. Cholesterol-3 beta-sulfate was not desulfated by the alkylsteroidsulfatases nor were steroids or bile acids that were sulfated in positions other than the 3 position. The alkylsteroidsulfatases were induced by their substrates; bile acid sulfates, however, were poor inducers of the 3 beta-sulfatase and did not induce the 3 alpha-sulfatase activity. In intact bacterial cells, taurine and sulfite suppressed the induction of the alkylsteroidsulfatases and inhibited the activity of the arylsulfatase and alkylsteroidsulfatases. In cell homogenates, the arylsulfatase and alkylsteroidsulfatases activities were inhibited by sulfite and sulfate but not by taurine. Our results support the hypothesis that the main function of the steroidsulfatases in P. niger H4 is to provide the bacteria with sulfur for dissimilatory purposes.