《普通微生物学》第9章 微生物生态-教学课件（非AI生成）.ppt

Tuberculosis（肺结核）isleadingkilleramonginfectiousdiseasesworldwide.Patientwithlymphnodenecrosis（淋巴结坏疽）.AfricanAIDSpatientwithslimdiseaseSource:TropicalMedicineandParasitology,1997EndemicKaposi’sSarcoma（地方性Kaposi’s恶性毒瘤）,nodularforminanAIDSpatient.Source:AIDS,1997.微生物的分布教学片*Morethan20yearsago,researchersnoticedthatafuelcellcontainingmicroorganismscouldgenerateelectricity(31),buthowitoccurredwasamystery.Severalyearslater,researchersstarteddiscoveringthatcertainbacteriacouldtransferelectronstosolid-phaseacceptors,suchasironoxides(32).Iftheycouldreduceasolid-phaseacceptor,couldtheyalsotransferelectronstoasolid-phaseelectrodeactingasananodeinafuelcell?Theanswerwasaresounding“yes”(33,34).Thus,therevolutionaryconceptofamicrobialfuelcell(MFC)wasborn.Asshowninthediagram,anMFCoperatesinthesamemannerasdoesaconventionalfuelcell,exceptthatbacterialivingasabiofilmontheanodecatalyzetheoxidationofthefuel.TheMFCisstillatanearlyresearchstage,butitcanbearevolutionarybreakthroughforcapturingrenewableenergysources.Thebacterialcatalysisattheanodemakesitpossible,forthefirsttime,touserenewableorganicmaterial(biomass)asafuelforfuelcells.Incontrast,conventionalfuelscellsuseanexpensiveplatinumcatalystontheanodeandstillcanuseonlyhigh-gradeH2,whichisobtainedbyreformingpetroleum,anonrenewableenergyresource.Byoperatingatambienttemperatureandwithoutcombustion,anMFCcanmorethandoubleenergy-captureefficiencywhileeliminatingairpollution.RecentworkshowsthatspecializedbacteriaarenotnecessarytogenerateelectricityfromorganicsinanMFC(35),butinspirationcomesfromthefundamentalstudiesonphysiology,ecology,andgenomicsofparticularmetal-reducingbacteria.(2)氨化作用(anmlonification)氨化作用是含氮有机物经微生物的分解转化成氨(铵)的过程。微生物可以在好氧和厌氧环境中、发生