绪论细菌基本性状

MedicalMicrobiologyWestChinaSchoolofPreclinicalandForensicMedicine

Dept.ofmedicalMicrobiologyLIWanyi（李婉宜）IntroductionMicroorganisms(Microbes)MicrobiologyMedicalMicrobiologyI.MicroorganismsMicroorganismsaredistributedallovertheworld.Toosmalltobeseenbythenakedeye,itisnecessarytousemicroscopetoexaminethem.1.1definition

1.2Characteristics

（1）Verysmallbodiesandsimplystructure.（2）Tomultiplerapidlyandmutanteasily.（3）MultiTypeandwidespread

acellularMicrobe

ProkaryoticMicrobe

EukaryoticMicrobe

1.3Classificationvirusbacteria，actinomyces，rickettsia，chlamydia，mycoplasma，spirochete

fungi

2.DistributionofmicroorganismsAirSoilWaterAnimalsHumanbody3.MicroorganismsandHumanBeingsMostmicrobesareofbenefittohumanbeings,somearenecessaryThecycleofmaterials2.Industrialproduction3.Agricultureproduction4.Medicalindustry.5.Geneticengineering.CycleofnitrogenCycleofcarbonGeneticengineeringAportionofmicrobescausediseasesandarepoisonoustohuman4.MicrobiologyItisabioscienceforthestudyoftheevolution,Classification,morphology,physiology,genetics,ecology,thelawoftheirlifeactivities,andtheirinteractionwithhumanbeing,animalsorplantsaswellaswithnaturalenvironment.5.MedicalMicrobiologyThemedicalmicrobiologyisoneoftheessentialbasicsciencesformedicine.ItisthestudyofBiologicalcharacteristicsofmicrobe,Pathogenicmechanism,ImmunologicmechanismandDiagnosis,Prevent,andTreatmentofinfectiousdisease.HistoryofMedicalMicrobiologyExperiencephaseExperimentalphaseModernphaseExperiencephaseExperimentalphaseLeeuwenhoekPasturKochListerIsolationFromthepatientsbutnothealthypeopleGrowthObtainpurecultureInducedisease

InfectsusceptibleanimalsRe-isolationFromthesusceptibleanimalsKoch'spostulates

ModernphaseEmergingandRe-emergingpathogenicmicroorganismBacterialgenomesequencing

Vaccinestudy

DevelopmentofMedicalMicrobiology新现及再现病原微生物的研究病原微生物致病机制的研究建立标准化的微生物学诊断方法及技术抗感染免疫的理论及应用研究（研制新疫苗）抗感染药物的研究与开发关注极端环境中的微生物，开发利用微生物资源Chapter1BasicCharactersofbacteriaBacterialShapeandStructure

1.

SizeofbacteriaUnitformeasurement:

Micronor

micrometer(μm)

Size:

Varieswithkindsofbacteria,andalsorelatedtotheirageandexternalenvironment.2.BasicshapeofbacteriacoccusbacillusSpiralbacteriumDiplococcusStreptococcusTetradSarcinaStaphylococcusBacillushemorrhagicE.coliBacillusanthracisCoccobacilliclostridumc.diphtheriaeSpiralbacteriumVibrioSpirillumVibriocholerae干酪螺菌鼠咬热螺菌

Basicshapesandarrangementofthebacteria细菌的异常形态▬衰退型MycobacteriumtuberculosisGramstainX1000

3.

StructureofthebacteriacellBasicstructureCellwallCellmembraneCytoplasmNucleoid

SpecialstructureCapsuleFlagellumPiliSpore3.1Basicstructure3.1.1cellwall

back-bone:

N-acetylmuramicacid

N-acetylglucosamine

β-1.4glycosidic

sidechain(tetra-peptide)

peptidecross-bridgePeptidoglycanofG+Nacetylglucosamine

N-acetylmuramicacidAsegmentofthepeptidoglycanAsegmentofthepeptidoglycanPeptidoglycanofG-

back-bone:

N-acetylmuramicacid;

N-acetylglucosamine

β-1.4glycosidic

sidechain(tetra-peptide)peptidoglycanteichoicacid

specialcomponentofG+cellwall

Therearetwotypesofteichoicacid:Wallteichoicacidandmembraneteichoicacid

FunctionofteichoicacidHelppeptidoglycantostrengthencellwallMainantigenofG+Relatedwithpathogenicityofbacterium

specialcomponentofG-cellwall脂多糖脂蛋白肽聚糖脂质双层lipopolysaccharide,LPSTargetforpencillinTargetforlysozyme

ComparisonofcellwallforG+

and

G_

componentG+G-peptidoglycanthickerthinnerTeichoicacidyesnolipopolysaccharidenoyesPNC+_antigenicitytechoicacidLPS

FunctionofcellwallMaintaintheshapeofbacteriaProtectfromlowosmoticpressurePermeabilitySurfaceantigenicdeterminates.Relatewithbacterialpathogenicity1、微生物分为哪几类？各类微生物具有那些特点？2、比较革兰阳性菌与革兰阴性菌细胞壁结构的异同。细胞壁有哪些重要功能？3.结合细胞壁结构及抗生素作用靶点，分析溶菌酶及青霉素对阴阳性菌的作用效果。预习：细菌的其它基本结构及特殊结构思考题李婉宜:联系电话：85501258E-mail:hxliwanyi@126.com

Reference

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