版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請(qǐng)進(jìn)行舉報(bào)或認(rèn)領(lǐng)
文檔簡介
Faculty:Dr.AlvinFoxSuggestedreading:Murray,Thirdedition Chapter2,16-18and21.TOPIC:CLASSIFICATION&IDENTIFICATIONOFINFECTIOUSAGENTS.Faculty:Dr.AlvinFoxSuggest1KeyTermsIsolation(culture)Agarplate/coloniesLiquidmediatesttube-bulkIdentification&taxonomyFamilyGenusSpeciesTypeStrainBiochemical(physiological)testsMoleculartestsDNA-DNAhomology16SrRNAsequencingChemicalprofiling NonculturebaseddetectionPolymerasechainreaction-(PCR)Agglutination(antigendetection)StainSerology(antibodydetection).KeyTermsIsolation(culture)Id2Bacterialidentificationinthediagnosticlaboratory1.Isolation&identificationaidstreatmentsinceinfectiousdiseases causedbydifferentbacteriahaveavarietyofclinicalcoursesandconsequences.Susceptibilitytestingofisolateshelpsinselectionofantibiotics fortherapy.Theidentificationisbasedontaxonomicprinciplesappliedto theclinicalmicrobiologicalsituation.4.Testsmustbeeasilylearned,lowincostandrapidlyperformed..Bacterialidentification1.3ClassificationFamily:agroupofrelatedgenera.Genus:agroupofrelatedspecies.Species:agroupofrelatedstrains.Type:setsofstrainwithinaspecies(e.g.biotypes,serotypes).Strain:onelineorasingleisolateofaparticularspecies..ClassificationFamily:agroup4StepsindiagnosticisolationandidentificationofbacteriaStep1.Samplesofbodyfluidsarestreakedoncultureplatesandisolatedcoloniesofbacteriaappearafterincubation.Observationofthesecoloniesforsize,texture,color,and(ifgrownonbloodagar)hemolysisreactions,ishighlyimportantasafirststepinbacterialidentification.Whethertheorganismrequiresoxygenforgrowthisanotherimportantdifferentiatingcharacteristic..Stepsindiagnosticisolation5BloodAgarPlate.BloodAgarPlate.6Step2.ColoniesareGramstainedandindividualbacterialcellsobservedunderthemicroscope..Step2.ColoniesareGramstai7Asinglecolonyisplacedonaslideanddried.Stage1.Stainingwithcrystalviolet.Stage2.Fixationwithiodinestabilizescrystalvioletstaining.Allbacteriaremainpurpleorblue.Stage3.Extractionwithalcohol.Decolorizessomebacteria (Gramnegative)andnotothers(Grampositive).Stage4.Counterstainingwithsafranin.Grampositive bacteriaarestainedwithcrystalvioletandremain purple.Gramnegativebacteriaarestainedpink.GramStain.Asinglecolonyisplacedona8..9GramstainmorphologyShapecocci(round)bacilli(rods)spiralorcurved(e.g.spirochetes)Singleormultiplecellsclusters(e.g.streptococci)chains(e.g.streptococci)Grampositiveornegative.GramstainmorphologyShape.10..11..12Step3.Thebacteriaarespeciatedusingtheseisolatedcolonies.
.Step3.Thebacteriaarespeci13TypicalCultureLaboratoryBench.TypicalCultureLaboratoryBen14Step4.Antibioticsusceptibilitytestingisperformed..Step4.Antibioticsusceptibil15TaxonomiccharacterizationofbacteriaComparisonsofspeciesinvolvecomparisonsof multiplestrainsforeachspecies.Comparisonsareprimarilybasedonchemicalor molecularanalysis..Taxonomiccharacterizationof16MolecularanalysisItwouldbeidealtocomparesequencesofentirebacterialchromosomalDNA.Alternatively,genomicsimilarityhasbeenassessedbytheguanine(G)+cytosine(C)content(%GC).Thishasbeenreplacedbytwoalternatives:HybridizationSequencingspecificgenes.MolecularanalysisItwouldbe17DNA-DNAhomology1.HowwelltwostrandsofDNAfromdifferent bacteriabind(hybridize)together. Thistechniqueisemployedtocomparethe geneticrelatednessofbacterialstrains/species.IftheDNAfromtwobacterialstrainsdisplaya highdegreeofhomology(i.e.theybindwell)the strainsareconsideredtobemembersofthesame species..DNA-DNAhomology1.Howwellt18“Goldstandard"inbacterialtaxonomySequencingof16SribosomalRNAmolecules(16SrRNA)The16SrRNAisapproximately1600nucleotidesinlength.The16SrRNAprovidesgenomicsimilarityabovethe specieslevelallowingcomparisonsofrelatednessacross theentirebacterialkingdom.CloselyrelatedbacterialspeciesoftenhaveidenticalrRNA sequences.5. Thetechniqueprovidescomplementaryinformationto DNA-DNAhybridization.
Thedevelopmentofprobesbasedon16Sdatahaveimproved identificationofsomebacterialpathogens..“Goldstandard"inbacterialt19ChemicalanalysisSophisticatedtoolsareavailableforstudyingthestructuralcompositionofbacteria(mostcommonlyfattyacid,carbohydrateorubiquinoneprofiling)ofbacteria.Characterizationofsecretedmetabolic
products(e.g.volatilealcoholsandshortchainfattyacids)isalsohelpful..ChemicalanalysisSophisticate20Approachestorapiddiagnosiswithoutpriorculture
Certainhumanpathogenseithercannotbeisolatedinthelaboratorygrowextremelypoorly.Successfulisolationcanbeslowandinsome instancesimpossible.3.Directdetectionofbacteriawithoutcultureis possibleforsomeorganisms..Approachestorapiddiagnosis21AsimpleapproachtorapiddiagnosisAntigendetection Usedinmanydoctor'sofficesforthegroupAstreptococcus.Thepatient'sthroatisswabbedandstreptococcalantigenextracteddirectlyfromtheswab(withoutpriorbacteriologicalculture).Thebacterialantigenisdetectedbyaggregation(agglutination)ofantibodycoatedlatexbeads..Asimpleapproachtorapiddia22BacterialDNAsequencesamplifieddirectlyfromhumanbodyfluidsThepolymerasechainreaction(PCR)canbeusedtoamplifylargeamountsofspecificgenesorportionsofgenes.Greatsuccesshasbeenachievedinrapiddiagnosisoftuberculosis..BacterialDNAsequencesamplif23DirectmicroscopicobservationCertainclinicalsamplessuchassputumcanbedirectlyassessedforthepresenceofbacteriacanbehelpful(e.g.detectionofM.tuberculosis
insputum)..Directmicroscopicobservation24SerologicidentificationSerologicidentificationofanantibodyresponse(inpatient'sserum)totheinfectingagentcanonlybesuccessfulseveralweeksafteraninfectionhasoccurred..SerologicidentificationSerolo25Faculty:Dr.AlvinFoxSuggestedreading:Murray,Thirdedition Chapter2,16-18and21.TOPIC:CLASSIFICATION&IDENTIFICATIONOFINFECTIOUSAGENTS.Faculty:Dr.AlvinFoxSuggest26KeyTermsIsolation(culture)Agarplate/coloniesLiquidmediatesttube-bulkIdentification&taxonomyFamilyGenusSpeciesTypeStrainBiochemical(physiological)testsMoleculartestsDNA-DNAhomology16SrRNAsequencingChemicalprofiling NonculturebaseddetectionPolymerasechainreaction-(PCR)Agglutination(antigendetection)StainSerology(antibodydetection).KeyTermsIsolation(culture)Id27Bacterialidentificationinthediagnosticlaboratory1.Isolation&identificationaidstreatmentsinceinfectiousdiseases causedbydifferentbacteriahaveavarietyofclinicalcoursesandconsequences.Susceptibilitytestingofisolateshelpsinselectionofantibiotics fortherapy.Theidentificationisbasedontaxonomicprinciplesappliedto theclinicalmicrobiologicalsituation.4.Testsmustbeeasilylearned,lowincostandrapidlyperformed..Bacterialidentification1.28ClassificationFamily:agroupofrelatedgenera.Genus:agroupofrelatedspecies.Species:agroupofrelatedstrains.Type:setsofstrainwithinaspecies(e.g.biotypes,serotypes).Strain:onelineorasingleisolateofaparticularspecies..ClassificationFamily:agroup29StepsindiagnosticisolationandidentificationofbacteriaStep1.Samplesofbodyfluidsarestreakedoncultureplatesandisolatedcoloniesofbacteriaappearafterincubation.Observationofthesecoloniesforsize,texture,color,and(ifgrownonbloodagar)hemolysisreactions,ishighlyimportantasafirststepinbacterialidentification.Whethertheorganismrequiresoxygenforgrowthisanotherimportantdifferentiatingcharacteristic..Stepsindiagnosticisolation30BloodAgarPlate.BloodAgarPlate.31Step2.ColoniesareGramstainedandindividualbacterialcellsobservedunderthemicroscope..Step2.ColoniesareGramstai32Asinglecolonyisplacedonaslideanddried.Stage1.Stainingwithcrystalviolet.Stage2.Fixationwithiodinestabilizescrystalvioletstaining.Allbacteriaremainpurpleorblue.Stage3.Extractionwithalcohol.Decolorizessomebacteria (Gramnegative)andnotothers(Grampositive).Stage4.Counterstainingwithsafranin.Grampositive bacteriaarestainedwithcrystalvioletandremain purple.Gramnegativebacteriaarestainedpink.GramStain.Asinglecolonyisplacedona33..34GramstainmorphologyShapecocci(round)bacilli(rods)spiralorcurved(e.g.spirochetes)Singleormultiplecellsclusters(e.g.streptococci)chains(e.g.streptococci)Grampositiveornegative.GramstainmorphologyShape.35..36..37Step3.Thebacteriaarespeciatedusingtheseisolatedcolonies.
.Step3.Thebacteriaarespeci38TypicalCultureLaboratoryBench.TypicalCultureLaboratoryBen39Step4.Antibioticsusceptibilitytestingisperformed..Step4.Antibioticsusceptibil40TaxonomiccharacterizationofbacteriaComparisonsofspeciesinvolvecomparisonsof multiplestrainsforeachspecies.Comparisonsareprimarilybasedonchemicalor molecularanalysis..Taxonomiccharacterizationof41MolecularanalysisItwouldbeidealtocomparesequencesofentirebacterialchromosomalDNA.Alternatively,genomicsimilarityhasbeenassessedbytheguanine(G)+cytosine(C)content(%GC).Thishasbeenreplacedbytwoalternatives:HybridizationSequencingspecificgenes.MolecularanalysisItwouldbe42DNA-DNAhomology1.HowwelltwostrandsofDNAfromdifferent bacteriabind(hybridize)together. Thistechniqueisemployedtocomparethe geneticrelatednessofbacterialstrains/species.IftheDNAfromtwobacterialstrainsdisplaya highdegreeofhomology(i.e.theybindwell)the strainsareconsideredtobemembersofthesame species..DNA-DNAhomology1.Howwellt43“Goldstandard"inbacterialtaxonomySequencingof16SribosomalRNAmolecules(16SrRNA)The16SrRNAisapproximately1600nucleotidesinlength.The16SrRNAprovidesgenomicsimilarityabovethe specieslevelallowingcomparisonsofrelatednessacross theentirebacterialkingdom.CloselyrelatedbacterialspeciesoftenhaveidenticalrRNA sequences.5. Thetechniqueprovidescomplementaryinformationto DNA-DNAhybridization.
Thedevelopmentofprobesbasedon16Sdatahaveimproved identificationofsomebacterialpathogens..“Goldstandard"inbacterialt44ChemicalanalysisSophisticatedtoolsareavailableforstudyingthestructuralcompositionofbacteria(mostcommonlyfattyacid,carbohydrateorubiquinoneprofiling)ofbacteria.Characterizationofsecretedmetabolic
products(e.g.volatilealcoholsandshortchainfattyacids)isalsohelpful..ChemicalanalysisSophisticate45Approachestorapiddiagnosiswithoutpriorculture
Certainhumanpathogenseithercannotbeisolatedinthelaboratorygrowextremelypoorly.Successfulisolati
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請(qǐng)下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請(qǐng)聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會(huì)有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 人人文庫網(wǎng)僅提供信息存儲(chǔ)空間,僅對(duì)用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對(duì)用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對(duì)任何下載內(nèi)容負(fù)責(zé)。
- 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請(qǐng)與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對(duì)自己和他人造成任何形式的傷害或損失。
最新文檔
- 2011年公務(wù)員國考《申論》真題卷及答案(副省級(jí))
- 獨(dú)生子女證辦理委托書(33篇)
- 工程管理心得體會(huì)
- 教學(xué)研討心得
- 幼兒園小班元宵節(jié)活動(dòng)總結(jié)
- 母親生日宴上的致辭
- 數(shù)字1~10教案模板5篇
- 山西省2017年中考數(shù)學(xué)真題試卷(含答案)
- 智慧學(xué)校智能化校園系統(tǒng)建設(shè)方案
- 5.2 生活中的透鏡課件八年級(jí)物理上冊(cè)(人教版2024)
- 2024年醫(yī)院醫(yī)療質(zhì)量管理與考核細(xì)則范文(三篇)
- 《國家的兒子》教案 2023-2024學(xué)年高教版(2023)中職語文基礎(chǔ)模塊上冊(cè)
- 【新生代】2024H1休閑零食品牌健康追蹤分析
- 2024年產(chǎn)品代理合同范本(二篇)
- 2024年秋新滬教牛津版英語三年級(jí)上冊(cè) Unit 4 第3課時(shí) 教學(xué)課件
- 2024年全國統(tǒng)一高考數(shù)學(xué)試卷(新高考Ⅱ)含答案
- 2023河南鄭州熱力集團(tuán)限公司招聘歷年高頻難易度、易錯(cuò)點(diǎn)模擬試題(共500題)附帶答案詳解
- 2023-2024學(xué)年天津市和平區(qū)七年級(jí)上學(xué)期期中質(zhì)量調(diào)查數(shù)學(xué)試題(含答案)
- YY/T 1610-2018麻醉和呼吸設(shè)備醫(yī)用氧氣濕化器
- 《詩經(jīng)-魏風(fēng)-伐檀》PPT優(yōu)秀課件
- 全國頭孢生產(chǎn)廠家
評(píng)論
0/150
提交評(píng)論