生物柴油原料资源高油脂微藻的开发利用

生物工程学报ChinJBiotech2008,March25;24(3):341-3[e-mail]©2008InstituteofMicrobiology,CAS&CSM,AllrightsreservedReceived:July23,2007;Accepted:September5,2007Supportedby:theNationalScienceFoundationofChina(No.30670493),TianjinKeyProjectsofScienceandTechnology(No.04318271),TianjinScienceandTechnologyDevelopmentalFundsofUniversitiesandColleges(No.20060724)andExceptionalTalentedPersonsInitialFundsofTUST(No.20060411)Correspondingauthor:DingjiShi.Tel:[phone];Fax:[phone];E-mail:[e-mail],[e-mail]国家自然科学基金(No.30670493),天津市科技攻关重点项目(No.04318271),天津市高等学校科技发展基金计划项目(No.20060724)和天津科技大学人才引进启动基金(No.20060411)资助。综述宋东辉1,侯李君1,施定基1,21,3004572,100093:生物柴油作为化石能源的替代燃料已在国际上得到广泛应用。至今生物柴油的原料主要来自油料植物,但与农作物争地的情况以及较高的原料成本限制了生物柴油的进一步推广。微藻作为高光合生物有其特殊的原料成本优势,微藻的脂类含量最高可达细胞干重的80%。利用生物技术改良微藻,获得的高油脂基因工程微藻经规模养殖,可大大降低生物柴油原料成本。介绍了国内外生物柴油的应用现状,阐述了微藻作为生物柴油原料的优势,对基因工程技术调控微藻脂类代谢途径的研究进展,以及在构建工程微藻中面临的问题和应采取的对策进行了综述和展望。:基因工程,微藻,油料植物,生物柴油ExploitationandUtilizationofRichLipids-microalgae,asNewLipidsFeedstockforBiodieselProduction–areviewDonghuiSong1,LijunHou1,andDingjiShi1,21LaboratoryofCyanobacterialandAlgalBiotechnology,CollegeofMarineScience&Engineering,TianjinUniversityofScience&Technology,Tianjin300457,China2InstituteofBotany,ChineseAcademyofSciences,Beijing100093,ChinaAbstract:Asarenewableenergysourcestoreplaceconventionalfossilfuels,biodieselfuelshavebeenbecomingincreasinglyre-quirementstoglobalfuelsmarket.Biodieselderivedfromoilcropscannotrealisticallysatisfyevenmorefractionoftherawmaterialexistingcostsandsoilcompetitivedemandforitsgrowth.Microalgaeappeartobetheadvantageofcoststhatiscapableofhigherphotosyntheticefficiency,largerbiomass,fastergrowthcomparedtothoseofoilcrops.Lipidcontentofmanymicroalgaeisusually80%ofitsdryweight.Geneticmicroalgaewithhigh-oilproductivitybygeneticmanipulationsarecapableofmakingmicroalgalbiodieseleconomicallycompetitivewithpetrodieselthroughlarge-scaleproductionofgeneticmicroalgalbiomass.Asdemonstratedhere,theuseofbiodieselfuelsinhomeandabroadarecurrentlyintroduced,andthecostadvantageofmicroalgaeastherawmaterialisanalyzed;Andmoreover,theprogressofmicroalgalgeneticengineeringinregulationoflipidmetabolismandtheproblemsintheconstructofgeneticmicroalgaestrainsaswellasapproachesformakingmicroalgalbiodieselappeartobeanimportantsourceofrenewablefuelthathasthepotentialtocompletelydisplacefossildieselarediscussedinthisreview.Keywords:geneticengineering,microalgae,oilcrops,biodiesel342ISSN1000-3061CN11-1998/QChinJBiotechMarch25,2008Vol.24No.3Journals.im.ac.cn,,,,,1生物柴油的优越性,,()()(),,:,,,;,;,SO2NO,,2/3,,[1],,2生物柴油原料的研发进展2.1世界各国制备生物柴油的原料,,50%~85%[2],,,,,2.2中国制备生物柴油的主要原料,,2003250t,20041~11625t,239t,56%;32t,1.18;216t,1.2[3]2005653t,433t,169.4t,50.6t,20101350t,72%[4],,,,,,,,?20031,,,20061112“”:,,[5],20%:343Journals.im.ac.cn:500t/,200t[6],2090,,,8000ha,,,,,,,,,3微藻成为制备生物柴油新型原料的优势,,,3.1已有油料植物作为生物柴油原料的成本劣势,,,,,,,,,3.2用藻类作为生物柴油原料与其他原料的比较,,,,,()(,1mm),,24h,3.5h[7],,(),CN,,50gm−2d−1,,C16C18[8]15%~20%,80%[9,10]18000km,,,,,4高油脂微藻的研究进展4.1高油脂微藻的筛选与生理生化调控研究1978,3000,300,50gm−2d−1,80%[9,10],,,,4.2应用基因工程技术构建高油脂工程微藻,,,,4.2.1与脂类合成有关的乙酰辅酶A羧化酶(acetyl-coenzymeAcarboxylase,ACCase)研究344ISSN1000-3061CN11-1998/QChinJBiotechMarch25,2008Vol.24No.3Journals.im.ac.cnA,A(acetyl-coenzymeAcarboxylase,ACCase),ACCase(1)图1大肠杆菌中ACCase的作用机制Fig.1ThereactionmechanismofE.coliacetyl-CoAcarboxylase(1)ThebiotinbondedwithACCaseiscarboxylatedbybiotincar-boxylase.(2)Thecarboxylgroupistransferredfromcarboxybiotintoacetyl-CoAtoformmalonyl-CoA(ExcerptfromDavisetal2000)ACCase,,ACCase2[11]ACCOhlroggenapinACCase,,T1ACCase12~19,6%[12]ACCase,ACCase,[13]ACCaseACCaseDavisACCase,ACCACCase,6[14]ACCaseACCase(NationalRenewableEnergyLaboratory,NREL)1991,;,1995ACCase,[15,16],,,ACCGenBank(1)ACCACCase,ACC4.2.2与脂类代谢有关的磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvatecarboxylase,PEPC)研究PEPC,,[17],ACCasePEPC,:,ACCaseA;APEPC,(2)PEPCACCasePEPC2050,1980,PEPC[18]1999,RNAPEPC,6.4%~18%,50%[19,20]2005,PEPC,[21],PEPC,20,[22](Anacystisnidulans)[23]7120(Anabaenasp.PCC7120,NostocPCC7120)[24](Synechococcusvulcanus)[25]PEPC,PEPC:345Journals.im.ac.cn表1GenBank中大肠杆菌及部分蓝藻的ACC基因(含推测的同源基因)*Fig.1TheACCgeneofEscherichiacoliandpartialcyanobacteria(includingdeductivehomologicalgenes)ACCgeneMicrobespeciesmRNA(nt)AminoacidnumberMolecularweight(kD)GenBankaccessnumberEscherichiacoli96032035.3D83536NostocpunctiformePCC7310298132635.9NZ_AAAY02000034Nostocsp.PCC712098132635.7NC_003272SynechococcuselongatusPCC630198432735.7AP008231SynechococcusPCC794298432735.7U59236accASynechocystissp.PCC680398132636.0NC_000911Escherichiacoli47115616.7M80458NostocpunctiformePCC7310255818519.7NZ_AAAY02000072Nostocsp.PCC712054918219.2NC_003272SynechococcuselongatusPCC630147715816.9AP008231SynechococcusPCC794247715816.9U59235accBSynechocystissp.PCC680346515416.3BA000022Escherichiacoli135044949.3M80458NostocpunctiformePCC73102134444749.3NZ_AAAY02000007Nostocsp.PCC7120134444749.1NC_003272SynechococcuselongatusPCC6301136245349.7AP008231SynechococcusPCC7942136240944.7U59234ac