微生物球菌专业知识讲解

Chapter9CoccusGramstainStaphylococcus(gram-positive)E.coli(gram-negative)CategoriesofcocciStaphylococcus（葡萄球菌属）Streptococcus（链球菌属）Neisseria（奈瑟菌属）Section1Staphylococcus（球菌属）

★Staphylococcusaureus（金黄色葡萄球菌）BiologicalcharacterizationPathogenesisandsymptomatology

★LaboratorydiagnosisEpidemiology,treatmentandcontrolStaphylococcusepidermidis（表皮葡萄球菌）Staphylococcussaprophyticus（腐生葡萄球菌）BiologicalcharacterizationMorphology:Gram-positivesphericalcellsarrangedingrape-likeclusters.LacksporeandflagellaCulturecharacteristics:Colonies:round,smooth,raised,glisteningPigments:fatsoluble;goldenyellow(pathogenic),whiteorlemonBloodagarplate:β-hemolysis(pathogenic)BiochemicalreactionsCatalase（触酶）test:+AntigensSPA★CapsularpolysaccharideOtherpolysaccharidesClassificationStaphylococcusaureus（金黄色葡萄球菌）

Staphylococcusepidermidis（表皮葡萄球菌）Staphylococcussaprophyticus（腐生葡萄球菌）Resistance:

relativelystrong,resistanttomanyantibioticsS.aureusmorphologyS.aureusmorphologyStaphylococcuscoloniesoncommonagarplatePigmentsS.aureus(goldenyellow)S.epidermidis(white)S.saprophyticus(lemon)Bloodagarplate,S.aureus

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βhemolysisCatalasetest★SPA葡萄球菌A蛋白StaphylococcalProteinADefinition:AcellwallcomponentofmanyS.aureusstrainsthatbindstotheFcportionofIgGmoleculesexceptIgG3.Invitro,SPAhasbecomeanimportantreagentinimmunologyanddiagnosticlaboratorytechnology.Invivo,SPAcaneffectivelydiminishopsonization.IgGFcSPAStaphylococcusIgGFcreceptormacrophageAnti-phagocytosis（抗吞噬）

Coagglutinationtest（协同凝集试验）FabSPAbindtoIgGFcAntigenStaphylococcusaggregation

PathogenesisandsymptomatologyPathogenicsubstances★EnzymesToxinsSurfacestructureproteinsAdhesin（黏附素）Capsule（荚膜）Peptidoglycan（肽聚糖）SPAEnzymesCoagulase（凝固酶）OtherenzymesFibrinolysin（纤维蛋白溶酶）Hyaluronidase（透明质酸酶）Heat-stablenuclease（耐热核酸酶）Lipase（脂酶）ToxinsStaphylolysin（葡萄球菌溶素）Leukocidin（杀白细胞素）Enterotoxin（肠毒素）Exfoliativetoxin（表皮剥脱毒素）TSST-1（毒性休克综合征毒素-1）Coagulase（凝固酶）Anenzyme-likeproteinproducedbyS.aureusthatclotsoxalatedorcitratedplasma.Itsproductionisconsideredasinvasivepathogenicpotential.Twotypes:Freecoagulase（游离凝固酶）Boundcoagulase（结合凝固酶）S.aureuscoagulasetestPositiveNegative凝固酶旳作用保护作用：抗吞噬，抗杀菌物质感染病灶旳病理特征：局限化、脓汁粘稠和形成血栓具有免疫原性Staphylolysin（葡萄球菌溶素）α,β,γ,δ-toxinsCytotoxin.Itisapotenthemolysin(溶血素).Actsonabroadspectrumofeukaryoticcellmembranes.(RBCs,WBCs,platelets,hepatocytes,etc.)Leukocidin（杀白细胞素）Cytotoxin.Damagethecellmembranesofneutrophilsandmacrophages.Inhibitphagocytosisandaggravatetissuedamage.Enterotoxin（肠毒素）Itis

agroupofsolubleandheat-stableproteins.Resistanttotheactionofgutenzymes.Animportantcauseoffoodpoisoning(食物中毒).Ingestionofenerotoxinresultsinvomiting(呕吐)anddiarrhea.Itisansuperantigen.食物中毒呕吐为主要症状Exfoliativetoxin（表皮剥脱毒素）Epidermolytictoxins(表皮溶解毒素)Theepidermolytictoxinsyieldthegeneralizeddesquamationofthestraphylococcalscaldedskinsyndrome（烫伤样皮肤综合征，SSSS）.Toxicshocksyndrometoxin-1毒性休克综合征毒素-1Ansuperantigen.Causestoxicshocksyndrome（TSS，毒性休克综合征）Associatedwithfever,shock,andmultisysteminvolvement.★ClinicalfindingsInvasivediseases(pyogenicinfection)Skinlesions:furuncle(疖),carbuncle(痈),impetigo(脓疮)Deeplesions:infectionsofbones,joints,deeporgans,andsofttissues.Systemicinfections:septicemiaandpyemiaToxin-mediateddiseasesStaphylococcalfoodpoisoning（食物中毒）Scaldedskinsyndrome(SSS)（烫伤样皮肤综合征）Toxicshocksyndrome(TSS)（毒性休克综合征）CutaneouslesionsofS.aureusBoil（疖）LaboratoryDiagnosisGramstain:Gram-positivecocciinclustersGoldenyellowpigmentCatalasetestsCoagulasetestsAntibioticsusceptibilitytestsBloodculturesIdentificationofthepathogenicstaphylococcus金黄色色素（+）溶血性（+）凝固酶（+）耐热核酸酶（+）发酵甘露醇（+）AntibioticsusceptibilitytestsSection2StreptococcusClassificationofStreptococciBasedonthecellwallantigensA~H.K~V20groups90%pathogenicstrainsbelongtogroupABasedonthehemolysisreactionsα–hemolysis–S.pneumoniae

andothersβ-hemolysis–

group

A,B,C,GandsomeDstrainsγ-hemolysisHemolysisClassificationbasedonhemolysis细菌类别别名溶血环溶血类型致病性甲型溶血性链球菌草绿色链球菌1～2mm草绿色甲型溶血/α溶血机会性致病菌乙型溶血性链球菌溶血性链球菌2～4mm全透明无色乙型溶血/β溶血致病力强丙型溶血性链球菌不溶血性链球菌无不溶血一般不致病GroupAstreptococcus（A群链球菌）BiologicalcharacterizationPathogenesisandsymptomatologyLaboratorydiagnosisEpidemiology,treatmentandcontrolBiologicalcharacterizationMorphology:Gram-positivespherical/ovoidcocciarrangedinlongchains.Non-spore-forming,nonmotileCanformcapsulesandpiliCulturecharacteristics:Facultativeanaerobes(兼性厌氧)Mostarefastidiousandrequireenrichedmedia(营养要求较高).Colonies:small,round,smooth,nonpigmentedBloodagarplate:β-hemolysis(pathogenic)BiochemicalreactionsCatalase（触酶）test:-AntigensPolysaccharideantigen(AntigenC)Groupspecificantigen（群特异性抗原）.MajorityofhumanpathogenicstreptococciaregroupA.ProteinantigenTypespecificantigen（型特异性抗原）ProteinMisamajorvirulencefactor.Nucleoproteinantigen(AntigenP):nonspecificResistance:

Sensitivetodrying,heat,anddisinfectantsStreptococcusStreptococcusHemolysispatterns

αhemolysisβhemolysisnohemolysisβhemolysisStreptococcus分20个群，A群致病（溶血性链球菌或化脓性链球菌）根据蛋白抗原进一步分型（M蛋白）多糖肽聚糖细胞膜细胞质荚膜蛋白质Pathogenesisandsymptomatology★

PathogenicsubstancesCellwallcomponentsAdhesin（黏附素）:LTA&proteinFProteinMPeptidoglycan（肽聚糖）ExotoxinsPyrogenicexotoxin（致热外毒素）Streptolysin（链球菌溶素）InvasiveenzymesHyaluronidase（透明质酸酶）Streptokinase（链激酶）Streptodonase（链道酶）Adhesin（黏附素）Lipoteichoicacid(LTA,脂磷壁酸)ProteinF(F蛋白)Bindtothecorrespondingreceptorsonhostcellsandfacilitatetheadherence.ProteinM（M蛋白）AmajorvirulencefactorofgroupAstreptococci.Facilitatestheadherence.Inhibitsphagocytosisandkillingofimmunecells.Acommonantigen(共同抗原).Contributestosomehypersensitivitydiseases.ViewofgroupAStreptococcus56Peptidoglycan（肽聚糖）PyrogenicDamagesplateletsIncreasesvascularpermeabilityInducesexperimentalarthritisPyrogenicexotoxin致热外毒素、红疹毒素、猩红热毒素Isassociatedwithstreptococcaltoxicshocksyndrome（链球菌毒性休克综合征）andscarletfever（猩红热）.PyrogenicHighlyantigenic.Actsasansuperantigen.Streptolysin（链球菌溶素）StreptolysinO(SLO,链球菌溶素O)Oxygen-labile(–SHgroups)RapidlyinactivatedinthepresenceofoxygenHighlyantigenicAntistreptolysinOtest(ASOtest)StreptolysinS(SLS,链球菌溶素S)Oxygen-stableNotantigenic.β-hemolysisonbloodagarplates.bothcausecellandtissueinjuryDamageRBCs,WBCsandplatelets.Hyaluronidase（透明质酸酶）Splitshyaluronicacid（透明质酸）,animportantcomponentofthegroundsubstanceofconnectivetissue.Aidsinspreadinginfectingmicroorganisms.Spreadingfactor（扩散因子）.Streptokinase（SK）链激酶Streptococalfibrinolysase（链球菌溶纤维蛋白酶）Ittransformstheplasminogen(纤维蛋白酶原)ofhumanplasmaintoplasmin(纤维蛋白酶),anactiveproteolyticenzymethatdigestsfibrin(纤维蛋白)andotherproteins.Spreadingfactor（扩散因子）Streptodonase（SD）链道酶Streptococaldeoxyribonuclease（链球菌DNA酶）DepolymerizesDNA.Spreadingfactor（扩散因子）链球菌感染病灶特点：脓汁稀薄，病灶扩散，边界不清★ClinicalfindingsPyogenicinfectionsInfectionsofskinandsubcutaneoustissues

Infectionsofothertissues:tonsillitis,pharyngitis,tympanitis,etc.

Toxin-mediateddiseasesScarletfever（猩红热）Streptococcaltoxicshocksyndrome（链球菌毒性休克综合征）AllergicdiseasesAcuterheumaticfever(ARF)（风湿热）Acuteglomerulonephritis（急性肾小球肾炎）StreptococcalskininfectionsPharyngitis（咽炎）andtonsillitis（扁桃体炎）Streptococcalsorethroat（咽炎）ScarletfeverLaboratorydiagnosisLaboratorydiagnosisSpecimens（标本采集）:Tobeobtaineddependuponthenatureofthestraptococcalinfection.Smears（涂片）:G+,spherical/ovoidcocci,arrangedinlongchains.Culture:bloodagarplates(hemolysis)Serologicaltests:ASOtest★ASOtest抗链球菌溶素O试验AntistreptolysinOtestisameasureofthebloodplasmalevelsofantistreptolysinO

antibodies

usedintestsforthediagnosisofa

streptococcalinfection

orindicateapastexposuretostreptococci.Itisusedtohelpdiagnosepost-streptococcalsequelaeofrheumaticfever(风湿热)andglomerulonephritis(肾小球肾炎).Streptococcusphenumoniae（肺炎链球菌）BiologicalcharacterizationPathogenesisandsymptomatologyLaboratorydiagnosisEpidemiology,treatmentandcontrolBiologicalcharacterizationMorphology:Gram-positive,lancet-shapeddiplococciNon-spore-forming,nonmotileCanformcapsulesCulturecharacteristics:Facultativeanaerobes(兼性厌氧)MostarefastidiousandrequireenrichedmediaColonies:small,round,smoothBloodagarplate:α-hemolysisAutolysis(自溶现象)BiochemicalreactionsBilebacteriolysistest:+Resistance:

Sensitivetodrying,heat,anddisinfectantsleft：αhemolyticstreptococcusnegative（turbidity）right：S.Pneumoniaepositive（clear、transparent）CapsuleS.PneumoniaeS.PneumoniaeCapsuleS.Pneumoniae

S.Pneumoniaeinsputum（Gramstain,×1000）S.Pneumoniae,bloodagarplate（αhemolysis）PathogenicityPathogenicsubstancesCapsulePneumolysinOLipoteichoicacidNeuraminidaseClinicalfindingsPneumococcalpneumoniaPneumococcalmeningitisOthercomplicationsLaboratorydiagnosisSmearsCultivationDistinguishedfromviridans(草绿色)streptococciα-hemolyticBilesolubilityOptochinsensitivityInulin(菊糖)fermentationQuellingreactionAnimaltoxicexperimentNeisseria（奈瑟菌属）Gram-negativecocciPairsPathogenicforhumans:

Neisseriameningitidis（脑膜炎奈瑟菌）Neisseriagonorrhoeae（淋病奈瑟菌）NeisseriaMeningitidis

(脑膜炎奈瑟菌)BiologicalcharacterizationMorphology:Gram-negative,kidney-shapeddiplococciCanformcapsulesandpiliCulturecharacteristics:Enrichedmedia:modifiedThayer-MartinmediumColonies:convex,glistening,elevated,mucoidAutolysis(自溶现象)Resistance:

weak露滴状菌落PathogenicityPathogenicsubstancesCapsuleAdhesivefimbriaeIgAproteaseLipooligosaccharide(LOS)Epidemicmeningitis流行性脑脊髓膜炎Naturehosts:humans(only)Portalofentry:thenasopharynx一般型暴发型