鞘氨醇杆菌_Sphingobac_省略_降解17_乙炔基雌二醇的代谢途径_任海燕

鞘氨醇杆菌(Sphingobacteriumsp.)JCR5降解17α-乙炔基雌二醇的代谢途径任海燕,纪淑兰＊,崔成武,王道(北京工业大学环境与能源工程学院,北京100022)摘要:从北京某避孕药厂污水处理站曝气池的活性污泥中分离得到1株能够以17α-乙炔基雌二醇(17α-ethinylestradiol,EE2)为唯一碳源和能源生长的菌株JCR5.通过对其形态特征、生理生化以及16SrDNA序列分析,鉴定该菌株为鞘氨醇杆菌属(Sphingobacteriumsp.).菌株JCR5在10d内对初始底物浓度为30mg·L-1EE2的降解率可达87%.该菌株能够利用甾体雌激素(甾酮、17β-雌二醇、雌三醇以及炔雌醇甲醚)、避孕药生产中间体以及一些芳烃化合物为唯一碳源生长.对EE2降解中间产物进行质谱分析推测,EE2在降解过程中首先被氧化为雌酮(estrone,E1),后经过一系列生物催化作用生成2-羟基-2,4-二烯-戊酸和2-羟基-2,4-二烯-1,6-己二酸2种中间代谢产物.前者是与ComamonastestosteroniTA441代谢睾甾酮的途径类似的产物,而后者是3-羟基-4,5-9,10-二断雌甾烷-1(10),2-二烯-5,9,17-三酮基-4-酸不同于前者断键位置的另一产物.关键词:17α-乙炔基雌二醇;鞘氨醇杆菌属;代谢途径;生物降解中图分类号:X172文献标识码:A文章编号:0250-3301(2006)09-1835-06收稿日期:2005-10-31修订日期:2005-12-17基金项目:北京市自然科学基金项目(8042007)作者简介:任海燕(1977～),女,博士研究生,主要研究方向为环境微生物及水污染控制,E-mail:r-h-y@126.com＊通讯联系人,E-mail:jshl@bjut.edu.cnDegradationpathwayof17α-EthynylestradiolbySphingobacteriumsp.JCR5RENHai-yan,JIShu-lan,CUICheng-wu,WANGDao(CollegeofEnvironmentandEnergyEngineering,BeijingUniversityofTechnology,Beijing100022,China)Abstract:Abacterialstrain,JCR5,whichdegrades17α-ethynylestradiol(EE2),wasisolatedfromactivatedsludgeofwastewatertreatmentplanttreatingwastewaterfrompharmacyfactorymainlyproducingcontraceptivemedicineinBeijing,China.Basedonitsmorphology,physiologybiochemicalpropertiesand16SrDNAsequenceanalysis,thisstrainwasidentifiedasSphingobacteriumsp.JCR5.StrainJCR5cangrowonEE2assolecarbonandenergysource.ThedegradationprocessforEE2withinitialconcentrationof30mg·L-1wasstudied,andtheresultindicatedthatthedegradationrateofEE2within10dayswas87%.ExperimentsofdifferentsubstratesshowedthatstrainJCR5cangrowonmanysubstratesotherthanEE2suchasseveralsteroidalestrogens(estrone,17β-estradiol,estriolandmestranol),theintermediatesincontraceptivemedicineprocessingandsomearomaticcompounds.MassspectrumanalysisdemonstratedthatEE2wasoxygenizedtoestrone(E1)firstly,and2-hydroxy-2,4-dienevalericacidand2-hydroxy-2,4-diene-1,6-dioicacidwerethemaincatabolicintermediatesduringEE2degradation.Theformeradoptedapathwaythatwasanalogicaltothepathwayofthepre