ESCHERICHIACOLITODECOMPOSEPOLLUTEDWATERANDSLUDGEBy刘琰,肖琦,邱思,金鑫2008.3.2BACKGROUND:污水生物处理技术——活性污泥法剩余污泥的处理问题筛选能特异性降解的微生物提高微生物的降解效率氧化磷酸化解偶联:解偶联是指将呼吸链的氧化作用与磷酸化作用分开的现象。在代谢物的氧化过程中ATP不产生或产生量减少,剩余能量以热能的形式放出。在解偶联的情况下,微生物为了获得满足生长需求的能量,势必会增大对营养物质的代谢消耗。chemicaluncouplingVSbiologicaluncouplingBIOLOGICALUNCOUPLING:1)ChangecomponentsoftherespiratorychainofE.coli2)Changeprotongradient3)MutatetheF1F0ATPsynthase1)RESPIRATORYCHAINOFE.COLIDifferentdehydrogenases(NADHdehydrogenasesⅠ,Ⅱ)Differentteminaloxidasesorreductases(Quinoloxidasesbo3-type&bd-type)Linkedbyquinones(Ubiquinone)NADHNDH1(nuo)2H+/e-NDH2(ndh)0H+/e-Quinonebo-typeoxidase(cyo)2H+/e-bd-typeoxidase(cyd)1H+/e-O2Fig1.AschematicrepresentationofseveralmajorcomponentsoftheaerobicrespiratorychainofE.coli2)CHANGEPROTONGRADIENTUncouplingprotein(UCP)主要存在于动物及一些高等植物中。当质子从UCP返回膜内而不经过ATPsynthase时,就发生解偶联。HOWTOEXPRESSUCP1INE.COLI?SignalpeptideAvoidofaggregationActivator:freefattyacid?Cofactor:CoQ?3)MUTATEATPSYNTHASEUncoupletheATPsynthesisandprotontransportTargetsites:β,δetcβS174L:decreaseenzymeactivitybutremainthecouplingtoprotontranslocation.cangrowbyoxidativephosphorylationSUMMARY1、敲除NDH1,bo-typeoxidase以减少protonpumping2、表达UCP,改变膜对氢离子的通透性3、突变ATPsynthase,降低ATP的合成