养虾池好氧反硝化细菌新菌株的分离鉴定及特征

第26卷第11期2OO6年l1月生态学报ACTAECOLOGICASINICAVo1．26．No．11]Nov．，2006养虾池好氧反硝化细菌新菌株的分离鉴定及特征廖绍安，郑桂丽，王安利，黄洪辉，孙儒泳(1．华南师范大学生命科学学院，广州510631；2．农业部渔业生态环境重点开放实验室，广州510300；3．广J州市疾病预防控制中心，广州510080)摘要：利用间歇曝气选择性富集并对所获菌株的好氧反硝化活性进行检测。筛选到一株亚硝酸盐去除活性较高的好氧反硝化细菌。在溶懈氧(D0)为3_8O一5．21mg／L的培养条件下。该菌株10h内将亚硝态氮由26．18mg／L降至0；在盐度为0—25之间20h内均可达到同样的去除效果。通过形态学特征、生理生化反应及部分长度16SrDNA序列分析对筛选菌株进行鉴定，初步判定它为嗜麦芽寡养单胞菌Stertotrophomonasmaltophilia。亚硝酸盐还原酶基因分析结果表明。该菌株只含亚硝酸盐还原酶nits基因，其序列与AlcaligenesfaecalisA15(后来被重新鉴定为Pseudomonasstutzeri)的nirS基因序列相似。关键词：好氧反硝化细菌；嗜麦芽寡养单胞菌；16SrDNA；亚硝酸盐还原酶nirS基因文章编号：100o．0933(2006)11-3718．07中圈分类号：Q93文献标识码：AIsolationandcharacterizationofanovelaerobicdenitrifierfromshrimppondLIAOShao．An，ZHENGGui．Li，WANGAn．Li’，HUANGHong．Hui，SUNRu-Yong(1．c02＆拓。SouthChinaNormalUniversity，Guangzhou510631，China；2．研LaboratoryofFisheryEcologyEnvironment，MinistryofAgriculture，Guangzhou510300，China；3．GuangzhouCenterforDiseaseControlandPrevention，Guangzhou510080。China)．AetaEeoiogieaSinica。2O06，26(11)：3718—3724．Abstract：Denitrifyingactivityofmosttypicaldenitrifiersisusuallycompletelysuppressedwhenanaerobiosisisinsufficient，aerobicdenitrifyingbacteriahasamajoradvantageinreducingnitrateand／ornitritetoN2underaerobicconditions，whichisc,-iticalfornitriteandnitrateremovalfromaerobicenvironment，suchasaquaculturewater．Aims：Toisolateaerobicdenitrifyingbacteriatoenhancenitrateandnitriteremovalfromaquaculturesystem．MethodsandResults：Selectiveenrichmentculturemethodunderalternatingoxic．anoxicconditionswasusedforscreeningbacteriathathavehighcapabilityofaerobicdenitrificationfromashrimppond．AnoveldenitrifierX0412wasisolatedandpurifiedafter2monthsofincubation．It，identifiedasStenotmphomonasmahophilia(formerlyreferredtoasXanthomonasmaltophilia)basedonitsbiochemicalandmorphologicalcharacters，isgroupedintothe7subclassoftheclassProteobacteria．Phylogeneticanalysisof16SrDNAsequencesindicatedthatstrainX0412wasmostcloselyrelatedtoS．mahophiliaAB021406．AnalysisofthebothnitritereductasegenesnirSandnirKshowedthatitcontainednirSgene，whichishighlyho