耐盐类固醇激素降解菌交替赤杆菌MH-B5的降解特性、降解途径及其固定化 |
摘要点击 3329 全文点击 2005 投稿时间:2015-06-19 修订日期:2015-07-20 |
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中文关键词 类固醇激素 睾酮 耐盐 代谢产物 固定化微生物 |
英文关键词 steroid hormone testosterone salt-tolerant metabolites immobilized bacteria |
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中文摘要 |
从咸水湖中分离得到1株具有类固醇激素降解能力的耐盐菌株,利用16S rRNA基因序列同源性分析确定菌株MH-B5属于交替赤杆菌属(Altererythrobacter),其可生长pH范围为5.5~9.0,可耐受盐度生长范围为0~7%,单碳降解实验表明该菌可以利用雌酮、雌二醇、雌三醇和睾酮. 应用超高压液相色谱串联四级杆飞行时间质谱分析得出菌株降解睾酮的过程中主要中间代谢产物为4-雄烯二酮、宝丹酮和雄二烯二酮. 应用单一载体和复合载体两种方法分别制备的菌株MH-B5固定化颗粒均可降解雌二醇, 批次降解实验表明菌株MH-B5固定化颗粒可有效降解 2 mg ·L-1雌二醇及其初级代谢产物雌酮. 上述研究结果表明菌株MH-B5可在海水中生长良好,其能降解典型雌激素及雄激素睾酮,且经过微生物固定化过程后依然具有类固醇激素的降解特性,因此对类固醇激素污染的咸水环境修复,具有潜在应用前景. |
英文摘要 |
A steroidal hormone degrading bacterium, named MH-B5, was isolated from saline lagoon. Several steroidal hormones including estrone, 17-β-estradiol, estriol and testosterone could be utilized as sole carbon source by strain MH-B5. Analysis of 16S rRNA gene sequence showed that it belonged to genus Altererythrobacter. Growth of strain MH-B5 was observed at salinities of 0-7% and at pH of 5.5-9.0. The main degradation metabolites of testosterone by strain MH-B5 were identified as 4-androstenedione, 1-dehydrotestosterone and androstadienedione using ultra performance liquid chromatography (UPLC) coupled to quadrupole time-of-flight mass spectrometry (Q-TOF MS). Mono-carrier and multi-carrier cell immobilization techniques were successfully applied to this steroid-degrading bacterium. Batch estrogen degradation study showed that immobilized strain MH-B5 could effectively degrade 2 mg ·L-1of 17β-estradiol and its metabolite estrone. The results mentioned above demonstrated the capability of MH-B5 to degrade both estrogens and testosterone and the potential application of using immobilized MH-B5 cells in bioremediation of steroidal hormone pollution in saline environment. |
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