microbiology

Definition

Researchonthelawsoflifeactivitiessuchasmicrobialmorphology,physiologyandbiochemistry,geneticvariation,ecologicaldistributionandclassificationevolution,andapplythemtoindustrialfermentation,medicalhygiene,bioengineeringandenvironmentProtectionandotherpracticalfieldsofscience.

Subjects

Microbiologyisanimportantbasiccourseorprofessionalbasiccourserequiredforbiologymajorsincollegesanduniversities,anditisalsothetheoreticalandtechnicalbasisofmodernhigh-techbiotechnology.Geneticengineering,cellengineering,enzymeengineeringandfermentationengineeringareformedanddevelopedonthebasisofmicrobiologyprinciplesandtechnology;microbiologyisalsooneoftheimportantcornerstonesforthedevelopmentofbiologicalmajorsandmodernizationofagricultureandforestryinhigheragriculturalandforestrycolleges.Withthewidespreadapplicationofbiotechnology,microbiologywillhaveahugeimpactonmodernandfuturehumanproductionactivitiesandlives.

Historicalorigin

Experiencestage

Sinceancienttimes,humanshavebeenawareofthelifeactivitiesofmicroorganismsandtheireffectsindailylifeandproductionpractices.ThehistoryofChina'suseofmicroorganismsforwinemakingcanbetracedbacktotheLongshanCultureperiodmorethan4,000yearsago.Thesaucemakingtechnologywasinvented2600yearsago.Theword"wine"isengravedintheoracleboneinscriptionsoftheYinandShangera.IntheQiMinYaoShu(533~544)byJiaSixieoftheNorthernWeiDynasty,methodsofmakingkojifromgrains,makingwine,makingsauce,makingvinegar,andpicklingvegetablesarelisted.

InthestonecarvingsleftbehindinancientGreece,thereisarecordoftheoperationprocessofwinemaking.DuringtheSpringandAutumnandWarringStatesPeriod,Chinausedthefunctionofmicroorganismstodecomposeorganicmattertodecontaminatemanureandaccumulatemanure.The"BookofPanSheng"inthefirstcenturyADproposedasystemofripemanurefieldsandintercroppingofmelonsandadzukibeans.Inthe2ndcentury"ShenNong'sMateriaMedica",thereisarecordofwhitebasssilkwormcuringdiseases.Inthe"ZuoZhuan"ofthe6thcentury,thereisarecordofthetreatmentofdiarrheawithwheatqu.Inthe10thcentury"YiZongJinJian",thereisarecordaboutthemethodofvaccination.In1796,theBritishJennerinventedthevacciniavaccine,whichlaidthefoundationforthedevelopmentofimmunology.

Morphologicalstage

Inthe17thcentury,theDutchmanLeeuwenhoekusedahomemadesimplemicroscope(whichcanbemagnified160to260times)toobservetartar,rainwater,wellwaterandplantinfusionLater,itwasdiscoveredthatthereweremany"tinyanimals"inmotion,andusedtextandpicturestoscientificallyrecordthedifferentformsofbacteria(spherical,rod-shaped,spiral,etc.)thathumanssawtheearliest"tinyanimals".Soonafter,theItalianbotanistP.AmiKellyalsousedasimplemicroscopetoobservethemorphologyofthefungus.In1838,GermanzoologistC.G.Inthebook"CiliatesareRealOrganisms",Ehrenbergdividedtheclassofciliatesinto22families,including3familiesofbacteria(heregardedbacteriaasanimals),andcreatedabacteria(bacteria)oneword.In1854,GermanbotanistF.J.Cosidiscoveredthesporesofrod-shapedbacteria.Heattributedthebacteriatotheplantkingdomanddeterminedthetaxonomicstatusofbacteriainthenexthundredyears.

Physiologicalstage

Theresearchofmicrobiologyhasenteredthephysiologicalstagesincethe1860s.FrenchscientistL.Pasteur'sresearchonmicrobialphysiologylaidthefoundationformodernmicrobiology.Pasteur,achemist,setfootinmicroorganismstotreat"winedisease"and"silkwormdisease."Hearguedthatthebrewingofwineandvinegarandthecorruptionofsomesubstancesarefermentationprocessescausedbycertaintypesofmicroorganisms,notfermentationorcorruptionthatproducesmicroorganisms.Thefamousretortexperimenthasindisputablyconfirmedthis;hebelievesthatfermentationItistherespirationofmicroorganismsinanenvironmentwithoutair,andthedeteriorationofwineistheresultofthegrowthofharmfulmicroorganisms;hefurtherprovesthatdifferentmicroorganismshaveuniquemetabolicfunctions,whichrequiredifferentlivingconditionsandcausedifferenteffects;heAheatsterilizationmethodtopreventdeteriorationofwinewasproposed,whichwaslatercalledPasteursterilizationmethod.Usingthismethod,thenewlyproducedwineandbeercanbestoredforalongtime.Kochhasmadegreatcontributionstotheemergingmedicalmicrobiology.KochfirstarguedthatBacillusanthracisisthecausativebacteriumofanthracnose,andthenhediscoveredthecausativebacteriaoftuberculosisandcholera,andadvocatedtheuseofdisinfectionandsterilizationmethodstopreventthespreadofthesediseases;hisstudentsalsodiscovereddiphtheria,pneumonia,tetanus,andplague.Suchpathogenicbacterialedpeopletoattachgreatimportancetobacteriaatthattimeandinthefollowingdecades;hepioneeredthestainingmethodofbacteria,usingagarasasolidificationmediumtocultivatebacteriaandseparatesinglecoloniestoobtainpureculture;HestipulatedthemethodsandproceduresforidentifyingpathogenicbacteriaandputforwardthefamousKoch'slaw.In1860,theBritishsurgeonJ.Listerapplieddrugstosterilizeandcreatedasterilesurgicaloperationmethod.In1901,thefamousbacteriologistandzoologistИ.И.Mechnikovdiscoveredtheeffectofwhitebloodcellsonphagocytosisofbacteriaandcontributedtothedevelopmentofimmunology.

Russian-bornFrenchmicrobiologistC.H.Basedonthediscoveryofsulfurbacteriain1887andthediscoveryofnitrifyingbacteriain1890,Vinogradzdemonstratedthemicrobiologicalprocessofsulfidationandnitrificationinsoilandthechemicalenergyandnutritioncharacteristicsofthesebacteria.Hewasthefirsttodiscovertheanaerobicautogenousnitrogen-fixingbacteria,andusedtheprinciplesandmethodsofinorganicculturemedium,selectiveculturemediumandenrichmentculturetostudythelifeactivitiesofvariousphysiologicalgroupsofsoilbacteria,andrevealedthatsoilmicroorganismsparticipateinthetransformationofsoilmaterials.Thisrolehaslaidthecornerstoneforthedevelopmentofsoilmicrobiology.

In1892,RussianplantphysiologistД.И.Ivanovskydiscoveredthattobaccomosaicpathogensareorganismsthataresmallerthanbacteria,canpassthroughbacterialfilters,andcannotbedetectedbyopticalmicroscopes.Theyarecalledfilterviruses.From1915to1917,F.W.TwaterandF.H.DeHerrelobservedtheappearanceofplaquesonthebacterialcoloniesandthelysisphenomenonintheculturesolution,andfoundbacterialviruses-phages.Thediscoveryofviruseshasexpandedpeople'sconceptofbiologyfromcellulartonon-cellular.

Inthisstage,theestablishmentofmicrobialmanipulationtechnologyandresearchmethodsisauniquesymbolofthedevelopmentofmicrobiology.

Biochemistrystage

Sincethe20thcentury,thepenetrationofbiochemistryandbiophysicsintomicrobiology,coupledwiththeinventionofelectronmicroscopeandtheapplicationofisotopetraceratoms,haspromotedmicroorganismsThedevelopmentoflearningtothestageofbiochemistry.In1897,theGermanscholarE.Bischnerdiscoveredthatthecell-freeextractofyeastcanfermentsugarliquidtoproduceethanollikeyeast,andthusunderstandtheenzymaticprocessofyeastalcoholfermentation,combiningmicrobiallifeactivitieswithenzymechemistry.G.Neubergetal.'sresearchonyeastphysiologyandtheanalysisofalcoholfermentationintermediateproducts,A.J.Kleivo’sresearchonmicrobialmetabolismandthecomparativebiochemicalresearchdirectionshepioneered,aswellasaseriesofbasicphysiologicalandmetabolicpathwaystudiesconductedbymanyotherpeopleusingEscherichiacoliasmaterials,haveclarifiedthelawsandregulationsofmetabolismoforganisms.Thebasicprincipleofcontrollingitsmetabolism,andexpandingtheuseofmicroorganismsonthebasisofcontrollingmicrobialmetabolism,developingenzymology,andpromotingthedevelopmentofbiochemistry.Sincethe1930s,peoplehaveusedmicroorganismsfortheindustrialproductionofethanol,acetone,butanol,glycerol,variousorganicacids,aminoacids,proteins,oils,etc.

In1929,A.FlemingdiscoveredthatPenicilliumcaninhibitthegrowthofStaphylococcus,revealedtheantagonisticrelationshipbetweenmicroorganismsanddiscoveredpenicillin.In1949,S.AWaxmandiscoveredstreptomycinbasedonthedataaccumulatedinhisyearsofstudyingsoilmicroorganisms.Sincethen,moreandmorenewantibioticshavebeendiscovered.Inadditiontomedicaluse,theseantibioticsarealsousedtocontrolanimalandplantdiseasesandfoodpreservation.

MolecularBiology

In1941,G.W.BiddleandE.L.TatumusedX-raysandultravioletraystoirradiateAlternaria,causingittomutateandobtainauxotrophs.Theirresearchonauxotrophscannotonlyfurtherunderstandtheroleandnatureofgenes,butalsolaythefoundationformoleculargenetics.In1944,O.T.Averyconfirmedforthefirsttimethatdeoxyribonucleicacid(DNA)isthesubstancethatcausesthegenetictransformationofpneumococcalcapsuleformation.In1953,J.D.WatsonandF.H.C.CrickproposedthedoublehelixstructuremodelofDNAmoleculesandthetheoryofhalf-reservednucleicacidreplication.H.Frankel-Conradandothersprovedthatribonucleicacid(RNA)isacarrierofgeneticinformationthroughtobaccomosaicvirusrecombinationexperiments,whichplayedanimportantroleinlayingthefoundationofmolecularbiology.Later,hediscoveredthemechanismoftransferribonucleicacid(tRNA),thetheoryofgenetripletcodes,themicrostructureofviruses,theprocessofinfectionandproliferation,andthemechanismofbiologicalnitrogenfixation,andotherimportanttheoriesinmicrobiology,demonstratingthebroadapplicationprospectsofmicrobiology..In1957,A.KornbergandotherssuccessfullycarriedouttheinvitrocombinationandmanipulationofDNA.Theresearchofprokaryoticmicrobialgenerecombinationhasmadecontinuousprogress.Insulinhasbeenfermentedwithgene-transferredEscherichiacoli,andinterferonhasalsobeenproducedbybacteria.Theresearchofmodernmicrobiologywillcontinuetodeepentothemolecularlevelanddeveloptothedepthandbreadthofproduction.Branches

Microbiologyhasexperiencedmorethanacenturyofdevelopment,andalargenumberofbrancheshavebeendifferentiated.Accordingtoincompletestatistics(1990),therehavebeenasmanyas181subjects.Accordingtoitsnature,itcanbesimplysummarizedintothefollowing6categories:

⑴Accordingtothepurposeofstudyingthebasiclawsoflifeactivitiesofmicroorganisms,thegeneralsubjectiscalledGeneralMicrobiology,anditisdividedintosubjects.Suchasmicrobialtaxonomy,microbialphysiology,microbialgenetics,microbialecologyandmolecularmicrobiology.

⑵Accordingtothemicrobialresearchobjects,suchasbacteriology,mycology(mycology),virology,prokaryoticbiology,autotrophicbacteriabiologyandanaerobicbacteriabiology,etc.

⑶Accordingtotheecologicalenvironmentwherethemicroorganismsarelocated,suchassoilmicrobiology,microecology,marinemicrobiology,environmentalmicrobiology,watermicrobiologyandcosmicmicrobiology.

⑷Accordingtothefieldofmicrobiology,itisdividedintogeneraldisciplinescalledAppliedMicrobiology,sub-disciplinessuchasindustrialmicrobiology,agriculturalmicrobiology,medicalmicrobiology,medicinalmicrobiology,DiagnosticMicrobiology,Antibiotics,FoodMicrobiology,etc.

⑸Accordingtotheintersectionandintegrationofdisciplines,suchaschemicalmicrobiology,analyticalmicrobiology,microbialbioengineering,microbialchemicaltaxonomy,microbialnumericaltaxonomy,microbialgeochemistryandmicrobialinformatics,etc.

⑹Accordingtoexperimentalmethodsandtechniques,suchasexperimentalmicrobiology,microbiologicalresearchmethods,etc.

Species

Overview

Themeaningofmicroorganisms:non-taxonomicnouns,derivedfromtheFrenchword"Microbe".Itisageneraltermforsmall,single-celledormulti-celledcellswithsimpleindividualstructure,andevenlowerorganismswithnocellstructure.

Type:Thegroupofmicroorganismsisverycomplex,including:viruseswithoutcellstructure,viroids,virus-like,etc.,

Prokaryotes,actinomycetes,rickettsiaeYeastsandmoldsbelongingtoeukaryotes,single-celledalgae,protozoa,etc.

Two-worldsystem

Animalia:Ithasnocellwall,canmove,anddoesnotperformphotosynthesis.

Plantaeoftheplantkingdom:hasacellwall,doesnotmove,andcancarryoutphotosynthesis.

ThreeRealms:Protista:(EHHaeckel,proposedin1866)

FiveRealmsSystem

ProkaryoteMonera:bacteria,actinomycetes,etc.

Protista:Algae,protozoa,slimemold,etc.

Fungi:Yeast,mold

Animalia:

Plantae:

TheFiveRealmsSystemisbasedonthelevelofcellstructuredifferentiationandthetissuetypesrelatedtothethreemainnutritionalmethodsofphotosynthesis,absorptionandfeeding.Sixrealms:plusthevirusrealm.

ThreeRealms(Domains)System

AfterWoesecomparedthe16SrRNAsequencesofmorethan60strainsofbacteriawiththeoligonucleotidesequencecataloginganalysismethod,hewassurprisedtofindthattherewerenomethanogenicbacteriaatall.Thosesequencesthatarecharacteristicofbacteria,soproposedthethirdformoflife-archaebacteria(archaebacteria).Subsequently,heperformed16SrRNA(18SrRNA)sequenceanalysisandcomparisonofalargenumberofstrains,includingsomeeukaryotes,andfoundthatextremehalophilesandextremeacidophilicbacteriaarealsothesameasmethanogenicbacteria,withdifferentandothercharacteristics.Bacteriaarealsodifferentfromthesequencefeaturesoftheirnuclearorganisms,andtheyhavemanycommonsequencefeatures.Soitwasproposedtodivideorganismsintothreekingdoms(Kingdom)(laterrenamedasthreedomains):Archaea,EubacteriaandEukaryotes.In1990,inordertoavoidseeingarchaeaasatypeofbacteria,herenamedthethreerealms(domains):Bacteria,ArchaeaandEukarya,andconstructedThephylogenetictreeofthethreerealms(domains).

Features

1.Smallsizeandlargespecificsurfacearea

Thesizeofmicroorganismsismeasuredinμm,butthespecificsurfacearea(surfacearea/volume)islarge,whichmusthaveahugenutrientabsorption,metabolicwasteexcretionandenvironmentalinformationacceptance.Thisfeatureisalsothekeytothedifferencebetweenmicroorganismsandalllargeorganisms.

Example:Lactobacillus:120,000;Eggs:1.5;People(200pounds):0.3

2.Highabsorptionandfasttransformation

Thischaracteristicprovidesasufficientmaterialbasisforhigh-speedgrowthandreproductionandtheproductionofalargenumberofmetabolites.

Forexample:3gramsofhamstersconsumefoodequaltotheirbodyweighteveryday;1gramofflashgreenhummingbirdconsumestwicetheirbodyweighteveryday;Escherichiacoliconsumes2000timesthebodyweightofsugarperhour;fermentedlactoseThebacteriacandecomposelactose1,000to10,000timesitsownweightwithin1hourtoproducelacticacid;1kilogramofyeastcellscanfermentthousandsofkilogramsofsugarinonedaytoproducealcohol

3.Prosperousgrowthandfastreproduction

Extremelyhighgrowthandreproductionspeed,suchasE.colisplitsevery20-30minutes.Ifitdoesnotstopdividing,thebacterialcountof2.2×10^43willincreasein48hours,nutrientconsumption,metabolicaccumulation,Limitgrowthrate.Thisfeaturecanconvertalargenumberofsubstratesintousefulproductsinashorttime,shorteningthescientificresearchcycle.Therearealsodownsides,suchasdiseaseandfoodmildew.Forexample:Escherichiacoli(E.coli)cellscandivideevery12.5-20minutesunderoptimalgrowthconditions;inliquidmedium,theconcentrationofbacterialcellsisgenerally108-109cells/ml;Brevibacteriumglutamicum:Shakebottleseed→50tonsfermenter:thenumberofcellscanincrease3.2billiontimesin52hours.Usingthisfeatureofmicroorganismscanrealizeshort-periodandhigh-efficiencyproductioninthefermentationindustry.Forexample,whenproducingfreshyeast,itcanbeharvestedonceinalmost12hours,anditcanbeharvestedhundredsoftimesayear.

Tablethegenerationtimeanddailyproliferationrateofseveralmicroorganisms

*istheoldnameofthegenusCandida(Nostoc),whichisthesameprokaryoteasthebacteria.

4.Strongadaptabilityandeasymutation

Extremelyflexibleandadaptable,withamazingadaptabilitytoextremeenvironments,andgeneticmaterialiseasytomutate.Moreimportantly,therearemanytypesofphysiologicalmetabolismandmetabolitesofmicroorganisms.Example:Microbeshavebeenfoundinsedimentaryrocksof10,000metersdeepsea,85kilometersabovethesky,128metersand427metersbelowtheformation.Thenumberofmicroorganisms,accordingto1972:

5.Widedistributionandmanytypes

Widedistributionareaandwidedistributionenvironment.Therearemanytypesofphysiologicalmetabolism,andtherearemanykindsofmetabolites.Moreimportantly,therearemanytypesofphysiologicalmetabolismandmetabolitesofmicroorganisms.Microorganismscanbefoundinanyenvironmentwhereotherorganismslive,andtherearealsomicroorganismsinextremeenvironmentswhereotherorganismscannotsurvive.

Forexample:Penicilliumchrysogenum(Penicilliumchrysogenum)produced20unitsofpenicillinpermilliliteroffermentationbrothin1943.Formorethan40years,throughtheunremittingeffortsofmicrobialgeneticbreedingworkersaroundtheworld,Thevariabilityofthebacteria'syieldhasgraduallyaccumulated,coupledwiththeimprovementoffermentationconditions,thefermentationlevelofadvancedcountriesintheworldhasexceeded50,000unitspermilliliter,orevencloseto100,000units.Thevariationofthequantitativetraitsofmicroorganismsandtheextentthatthebreedingcanincreasetheyieldisabsolutelyimpossibleintheworkofanimalandplantbreeding.Becauseofthis,almostallmicrobialfermentationfactoriesattachgreatimportancetostrainselectionandbreeding.

⒍Itiseasytomutateandproducemutations

Thesmallmicrobesandthelargespecificsurfaceareamakethemicrobeseasilyaffectedbyenvironmentalconditions.Certainnutritionalfactorschange,individualmicrobesconsciouslyandforcedtoproducegeneticstructuralchanges,resultinginvariants.Accordingtostatistics,theprobabilityofindividualmicrobialvariationisoneinamillionundernaturalconditions.Becausemicroorganismsarepronetoproducemutants,peopletakeadvantageofthecharacteristicsofmicroorganismstocarryoutmicrobialmutagenesis,andthenscreenformicroorganismstrainswithcertainpurposecharacteristics,suchasincreasedyield,auxotrophs,andsoon.

Role

1.Roleinmaterialcirculationinnature

2.Airandwaterpurification,sewagetreatment

3.Industrialandagriculturalproduction:bacteria,metabolites,metabolicactivities

4.Contributionstolifesciences

Researchdirections

Microbiologydisciplines:Chinaisoneofthecountrieswiththerichestmicrobialresourcesintheworld.Researchonmicrobialresourcesreflectsthelevelofbasicmicrobiologyresearch,isthebasisfornationalinvestigations,resourceprotection,developmentandsustainableuse,andisthebasisforbiodiversityresearchandendangeredspeciesprotection.Italsoincludesmicrobialmolecularbiologyandbiotechnology.Thefoundationofthevariousbranchesofmicrobiology.Researchinthisfieldwillacceleratetheinvestigation,collection,andsystematicclassificationofmicrobiologicalresources,expandthecollectionofmicrobialstrainsandspecimens,andestablishamicrobialspeciesresourcebankinChina,makingitthelargestmicrobialstraincollectioncenterinAsiaandthelargestinAsiaHerbariumofFungi.Insystematicclassificationstudies,newmethods,newtechnologies,andnewideasaregenerallyintroduced,andbiologicaldiversity,systemevolution,andmicrobialecologyresearcharecarriedouttoprovidematerialsforlarge-scalescreeningoffunctionalsubstances.Amongthem,extremophilesandmicroorganismsthatareharmfulorbeneficialtocropsTheresearchhasgraduallybecomethecurrenthotresearchfield.

Themajorresearchdirectionsofmicrobiologyinclude:fungiandlichenology,microbialresources,taxonomy,systematics,diversity,populationgeneticsandevolution,molecularmechanismofcooperativemetabolism,environmentalmicrobiology,industrialmicrobiology,systemsBiotechnology,microbialphysiology,microbialphysiology,microbialmetabolism,microbialecology,microbialbiochemicalengineering,molecularvirology,molecularimmunology.

Specificapplication

Modernclinicalmicrobiologyisacross-disciplinethatcombinesclinicalmedicine,basicmedicineandpreventivemedicine.Itisalsooneoftheimportantandmaturespecialtiesinlaboratorymedicine..Thisemergingdisciplinerequiresmicrobiologistsandlaboratorytechnicianstoworktogether.Therearefourspecifictasks:(1)Makerapidandaccurateinspectionreportsonmicrobialspecimenstomeetclinicalneedsinatimelymanner;(2)conductrelevantantimicrobialdrugresistanceVarioustrialsondrugproperties,acceptconsultationsontherationalapplicationofantibacterialdrugs;(3)Closelyintegrateclinicalpractice,discuss,researchanddealwithissuesrelatedtoinfectiousdiseaseswithclinicians;(4)participateinthemanagementandrationalapplicationofantibacterialdrugsHospitalinfectionmonitoring,controlandmanagement.Thisrequiresclinicalmicrobiologiststonotonlycompletelaboratorywork,butalsocompleterelatedclinicalwork,andbecomestaffandconsultantsforinfectioncontrolandclinicalapplicationofantibacterialdrugs.

Pathogenicdiagnosis

1.Ensurethereliabilityofclinicalspecimens:Properspecimencollectionisthemostimportantstepinthediagnosisofinfectiousdiseases.Cliniciansarerequiredtocorrectlycollectclinicalspecimensthatcanrepresentthesiteofinfection,andwidelyuseprotectiveswabs,qualifiedcontainers,andtransportmediatopreventthemicrobesinthespecimensfromdyingduetotoxicsubstances.

2.Comprehensiveunderstandingofthenormalfloraofthebody:Understandingthenormalfloraofthehumanbodyisanecessaryprerequisiteforbacterialtesting.Itisnecessarytounderstandtheconcept,distributionandtypesofnormalflora,conditionalpathogensandendogenousinfections,dysbacteriosisanddualityIntheconceptofinfection,neithershouldthebacteriaisolatedfromallspecimensberegardedaspathogenicbacteria,norcantheendogenousinfectioncausedbynormalcolonizingbacteriabeeasilyletgo.

3.Threesetsandonecombination:Qualitative,quantitativeandlocalizationanalysisshouldbedoneduringseparationandidentification,andcombinedwiththeconditionofthedisease.Itisrequiredtodeterminetheinspectionprocedure,selecttheculturemediumandtheappropriateidentificationtestaccordingtothespecificconditionsoftheclinicalandspecimens.Itisnecessarytodeterminewhethertheisolatedbacteriaarepathogenicbacteria,conditionalpathogenicbacteria,ornon-pathogenicbacteria(qualitative).Atthesametime,theremustbearoughestimateofthenumberofbacteria,andsemi-quantitativeandquantitativecultureshouldbecarriedoutifnecessary.Thesignificanceofthebacteriaisolatedinthehumanbodypartshouldbejudgedbyreferringtothequalitativeandquantitativeanalysisofthemicroorganism;ifthebacteriaareisolatedinthesterilepart(suchasblood,cerebrospinalfluid),nomatterwhatkindofmicroorganismandthequantity,itisimportantMeaning(positioninganalysis).Whenperformingthe"threedeterminations"analysis,wemustcombinetheconditionandobservewhetheritisconsistentwiththecondition.

4.Providefastandaccuratepathogenicdiagnosis:Whencliniciansprovidepatientswithclinicaldiagnosisinformationandappropriateclinicalspecimens,andobtainepidemiologicaldataasmuchaspossible,conductmicrobiologicalexaminationsandantimicrobialdrugsusceptibilitytests,requiringtimely,Comprehensivelyanalyzethetestresults,provideclinicallyaccuratepathogenicdiagnosis,sothatthepatientcanbetreatedappropriately.Althoughtheisolationandidentificationofmicroorganismsisstillregardedasthegoldstandardforpathogenicdetection,thetraditionalbacteriologicalidentificationmethodbasedonthe"growthoflivingbacteria"isslowandcannotadapttoclinicalneeds.Itisrequiredtobebasedondirectinspectionofspecimens.,Suchasmorphology,staining,antigendetectionandnucleicaciddetection(nucleicacidhybridization,PCRand16SrRNAanalysis),detectionofpathogenicgenes(pathogenicislands,virulenceislands)anddrugresistancegenes.Trytomakeaquickdiagnosisasmuchaspossible.

5.Timelyreporting:Inordertoeffectivelytransformlaboratorydataintoclinicallyusefulinformation,pathogenicmicroorganismdiagnosisreportsshouldimplementathree-stagereportingsystem,thatis,whenasmearorculturepositiveresultappears,whenasensitivetestresultcomesout,andafterthefinalresultcomesoutReportinatimelymanner.

6.Strengthenqualitycontrolandincreaseinspectionitems:Theclinicalmicrobiologyroommuststrengthenqualitycontroltoensuretheinspectionqualityofvariousspecimens,provideareliablebasisfortheclinic,andmeetthevariousinspectionitemsrequiredbytheclinic.Thecurrentclinicalmicrobiologyroomshouldaddtestitemsbasedontheactualsituationoftheunit.Someitemsthattheclinicalrequirementspayattentiontoare:1)bacteriologicalscreeningandsemi-quantitativeculturemethodsofrespiratoryspecimens;2)detectionofatypicalpathogensoftherespiratorytract,includingchlamydiaandmycoplasmaAndLegionella;3)non-tuberculousmycobacteriacultureanddrugsusceptibility;4)detectionofspecialpathogensinimmunosuppressedororgantransplantpatients,suchascytomegalovirus,pneumocystiscarinii,etc.;5)pathogensofantibiotic-relateddiarrhea(MainlythedetectionofClostridiumdifficile);6)therapiddetectionanddrugsensitivitytestofinvasivefungi.

Participateinclinicalconsultation

(1)Obtainclinicalinformationandmaketimelyandaccuratemicrobiologicalreports

ClinicalinfectiousdiseasesManypathogensareofteninvolved,andnosingletestcandetectallpotentialpathogens.Therefore,clinicalinformationisanimportantreferenceforselectingtestmethods.Theclinicianshouldwritedownthespeculativediagnosisofthepatientwhenissuingthelaboratorytestform,sothatthelaboratorystaffcanchooseareasonabletestprocedureandtestmethodbasedonthis,andcanguidetheclinictocollectappropriatespecimenscorrectly;whenthelaboratorybeginstohaveexperimentalresults,Cliniciansmustbenotifiedintimesothattheycanre-evaluatethediagnosisandtreatmentplan.

(2)Interpretationandconsultationofdifficultmicrobialreports

Manyinfectiousdiseases,especiallyhospitalinfections,havealargepathogenicspectrumanddrugsensitivityspectrum.Variety.Inthepast,raremicroorganismsfrequentlyappearedontheinspectionreport,andthemethodofdrugsusceptibilitytest,thetestedspecies,andtheinterpretationoftheresultshavealsochangedalot.Itisoftendifficultforclinicianstocorrectlyunderstandanduseclinicalmicrobiologicalexaminationdata.Inthefaceofthissituation,theclinicalmicrobiologydepartmentshouldactivelycommunicatewithclinicianstohelpsolvethedifficultiesofcliniciansininterpretingmicrobiologicaltestsanddrugsusceptibilityresultsreports.Pointouttheidentificationandjudgmentofnormalflora,contaminatedbacteriaandinfectiousbacteria;themeaningofrareorrarebacteria;possiblereasonswhencultureisnegative;judgmentcriteriaandlimitationsofdrugsusceptibilitytestresults;drugresistancecharacteristicsofspecialdrug-resistantbacteria,etc.,Andaddnotestothereportwhennecessary.

(3)Setupamicrobiologistasabridgebetweenclinicalandmicrobiologydepartment

Manyforeignhospitalshaveconsultationswithclinicalmicrobiologistsorlaboratoryphysicians,Consultationsystem.Ifthereisaproblemwiththesmearatthebeginningofthetest,theexaminershouldcontactthecliniciantodiscussthemeaningofthesmear.Physiciansandtechniciansinthemicrobiologydepartmentlookattheresultsofcultureanddrugsensitivitytogethereveryday,especiallytheresultsofsputumcultureshouldbecheckedwithdirectsmears,andcontactthewardintimeifproblemsarefound.

Itisrecommendedthataphysicianintheclinicalmicrobiologydepartmentparticipateinthemorningmeetingoftheinfectiondepartment,respiratorydepartmentorICUofourhospitaleveryday,andreturntoreportthesituationoftheinfectedpatienttothephysician.Orsenddoctorsregularlytobringrelevanttestresultsandparticipateininfectionseminarsinsomeclinicaldepartmentstospecificallysolvetheinfectiontreatmentproblems.Forexample,toparticipateinseminarsintheICU,transplantationdepartment,oncologydepartment,neurosurgery,pediatrics,etc.,forpatientswithpositivebloodculture,positivecerebrospinalfluidtest,orsevereburninfection,themicrobiologistshouldtaketheinitiativetovisitthewardandparticipateinthediscussionoftreatmentoptions.Forpatientswithbacteremiaorsepsis,assistinfindingtheprimaryfocus.Clinicalmicrobiologistsshouldrecordtheiropinionsinthemedicalrecordsafterpatrollingpatients,anddiscusswiththeclinicalphysiciananddirectorifnecessary.Ifeachclinicaldepartmenthasinfectionproblems,youcancontacttheclinicalmicrobiologydepartmenttoinquireaboutthesignificanceofthetestreportorrequestaconsultation.TheDepartmentofMicrobiologyholdsaseminaroninfectioncasesonceaweektodiscussthesituationofinfectedpatients,exchangefindings,andexchangeopinionsfromtheDepartmentofClinicalMicrobiologywiththeclinicaldepartment.Microbiologistsshouldalsoparticipateindailyinspectionsandreceiveclinicalconsultationsonmicrobiologicalissues.

Participateinantibacterialdrugs

Therationalapplicationofantibacterialdrugstoreduceoravoidtheproductionofdrug-resistantstrainsisamajorprobleminthecurrentanti-infectionfield.Theclinicalmicrobiologyroomplaysanimportantroleintherationaluseofantibiotics.effect.

Firstofall,wemustpayattentiontothepathogenicdiagnosisofinfection.Beforeusingantibacterialdrugs,cliniciansshouldcollectmultiplemicrobiologyspecimensforbacterialcultureanddrugsusceptibilitytesting.Themicrobiologydepartmentprovidesrapidandaccuratebacterialtestinganddrugsusceptibilityresultsfortheclinic.Inaddition,closecontactbetweenmicrobiologistsandcliniciansandparticipationinthetreatmentofpatientsisalsoanimportantmethodtocontrolthedosageofantibiotics.Microbiologistsshouldparticipateinthehospitalpharmacycommittee,participateintheformulationofguidelinesfortheuseofantibiotics,educationandtraining,supervisionandinspections,etc.Inthisregard,thepracticeofHongKongQueenMaryHospitalisthattheinfectionmonitoringnurseisresponsibleforvisitingtheinfectedcases.Whenthemisuseorunreasonableapplicationofantibacterialdrugsisfound,thedirectorofthemicrobiologydepartmentwillgivefeedbacktothedean,thedirectoroftherelevantdepartmentandtheparties,andachievebetterresults.

Participateinthemonitoring,controlandmanagementofnosocomialinfections

China’s"NosocomialInfectionManagementRegulations"clearlystatesthatthelaboratoryshouldperformthefollowingdutiesinthemanagementofnosocomialinfections:ResponsibleforroutinemicrobiologyofnosocomialinfectionsTocarryoutthecultivation,isolationandidentificationofpathogenicmicroorganismsofhospitalinfection,drugsusceptibilitytestinganddrugresistancemonitoringofspecialpathogens,regularsummaryandanalysis,feedbacktorelevantdepartments,andannouncementtothewholehospital;whennosocomialinfectionsareprevalentoroutbreaks,relevantInspectionwork.

Theroleofclinicalmicrobiologylaboratoryinthemonitoring,controlandmanagementofnosocomialinfectionsincludes:(1)strengtheningpathogenicmonitoringasthebasisfordeterminingnosocomialinfection;(2)strengtheningmonitoringofdrugresistancetoGuidetherationaluseofantibiotics;(3)Strengthenmicrobiologicalinvestigationsoftheenvironmentandequipmenttomeettherequirementsofhygieneindicators;(4)Ensurethequalityofdisinfectionandsterilizationinthehospital;(5)PassepidemiologicalinvestigationsandbacteriologicaltypingExperiment,tracethesourceofinfectionandcontrolit.

(1)Strengtheningsurveillance

Theclinicalmicrobiologydepartmentisaninevitablememberofthehospitalinfectioncontrolcommittee,andmicrobiologicaltestingplaysanimportantroleinthemonitoringofhospitalinfections.Ifahospitalinfectionproblemisfoundintheclinicalmicrobiologicalexamination,itisnecessarytocontactthehospitalinfectioncontroldepartment,thewarddoctorandtheheadnurseintime,andpayattentiontothedevelopmenttrend.Somespecialdrug-resistantbacteriainhospitalinfections,suchasGRE,MRSA,ESBL-producingenterobacteriaceae,etc.,areoftenspreadthroughcross-infection.AspergillusandLegionellaareoftenpresentinairconditioners,watersupplysystems,andatomizationdevicesandcauseinfections.Routinemonitoringofthesourceofthesepathogenicbacteriaandremindingclinicalattentioncanusuallyeffectivelypreventthespreadandsavealotofanti-infectioncosts.

(2)NosocomialinfectionEducationandtraining

TheclinicalmicrobiologydepartmentshouldparticipateinRelevantpersonnelcarryouteducationandtrainingofnosocomialinfections.Forexample,explaintherequirementsandprecautionsforthecollection,storage,andtransportationofclinicalmicrobialspecimens,whatpreparationsshouldbemadebypatientsbeforespecimencollection,whattimeandlocationshouldbeselectedforspecimencollection,howmanytimesaday,howmuchtocollect,andsamplinglocationExplainaseriesofissuessuchashowtodisinfect;trainthecommonhumanbody'snormalflora,colonizingbacteria,contaminatingbacteriaandinfectiousbacteria;thedetectionofvariousbacterialdrug-resistantenzymesanditsmeaningandthesignificanceintheselectionofantibioticsRegularcommunicationwiththeclinicandsoon.Variousmethodscanbeused,suchaslectures,seminars,briefings,posters,andevenparticipationinwardrounds.Itcanalsobeintegratedintocontinuingeducationandtrainingprogramsforhospitalinfectionmanagement.

(3)Participateinthemanagementofdisinfectionandisolation

Thecorrectandscientificimplementationofdisinfectionandisolationtechnologyisveryimportantforthepreventionandcontrolofnosocomialinfections.Correctguidance,Supervision,disinfectionandisolationisalsooneofthetasksoftheclinicalmicrobiologydepartment.Whenanoutbreakofnosocomialinfectionoraspecialdrug-resistantbacterialinfectionoccurs,clinicalmicrobiologyprofessionalsshouldparticipateintheformulationofdisinfectionandisolationmeasures,andprovideprofessionalmicrobiologicalopinionsonrelatedpersonnelmanagementandwastedisposal.

(4)RegularreleaseBacterialresistanceMonitoringresults

FormanyinfectionsThechoiceofantibacterialdrugsfordiseaseisempirical.However,empiricalmedicationalsoneedsthesupportofevidence-basedmedicineandepidemiologicaldata.ItisrecommendedtosaveallpathogenicbacteriaisolationanddrugsusceptibilitydatawithWHONETsoftware,regularlypublishbacterialdrugresistancemonitoringresults,statisticallyanalyzethedistributionanddrugresistancestatusofcommonpathogensinkeydepartmentssuchasICUatanytime,andchooseantibioticsforclinicalexperiencetoimprovesevereinfectionsThesuccessrateoftreatmentisveryhelpful.

(5)ControllingbymoleculartypingtechnologyNosocomialinfection

CommonlyusedmoleculartypingtechnologiesincludePFGE,RAPD,etc..Microbiologylaboratoriessetupmoleculartypinglaboratoriestoroutinelytypedrug-resistantbacteriathataremoreharmfulandeasytospread,whichisofgreatsignificancefortimelydetectionandcontrolofpathogenicbacteria.Thepracticeofsomeforeignhospitalsistocarryoutmoleculartypingofuncommondrug-resistantbacteriasuchasVREassoonastheyarediscovered.Accordingtothegenotyping,thepossibilityandscopeoftheepidemicwillbejudgedandcorrespondingmeasureswillbetakentocontroltheinfection.Forexample,ahospitalclassified19VREstrainsisolatedfrom16patientswithin2months,andtheresultsshowedthat14ofthemwereofonetypeandtheotherswereofonetype,whichhighlysuggestedtheprevalenceofVRE.Afterinvestigationandanalysis,itwasfoundthat1411ofthepatientshaddirectcontact.Basedontheseanalyses,targetedcontrolmeasuresweretakentostoptheinfection.Inotherhospitals,Klebsiellapneumoniae,Staphylococcusepidermidis,Staphylococcushemolyticus,Serratiamarcescensandotherinfectionepidemicshavebeencontrolledthroughmoleculartyping.Accordingtostatistics,thecostofestablishingamoleculartypinglaboratory(equipmentandpersonnel)inthemicrobiologylaboratoryis$180,050,andtheannualmoleculartyping-relatedexpenditureis$400,000.Assumingthatallhospitals(theUnitedStates)routinelyperformmoleculartyping,theexperiment-relatedcostsamounttoUS$2billion.,Butthesavedcostoftreatinghospitalinfectionswillbemorethan5times(10billionyuan).

Naming

Classificationunitsofmicroorganisms:world,phylum,class,order,family,genus,species

Speciesarethemostbasictaxonomicunits,eachAfterthetaxonomy,therecanbesubphylums,subclasses,suborders,subfamilies...

TakeS.cerevisiaeasanexample,itstaxonomicpositionis:

Kindom:Fungalkingdom

Phyllum:Fungus

Class:Ascomycete

Order:Endospora

Family:Endomyces

Genus:Saccharomyces

Species:Saccharomycescerevisiae

Species:Itisabasictaxonomicunit;itisthegeneraltermforalargegroupofstrainsthatarehighlysimilarinphenotypiccharacteristics,closelyrelatedtoeachother,andaresignificantlydifferentfromotherspeciesinthesamegenus.①Strainreferstoanypurebredpopulationandallitsdescendants(agroupofpurebreddescendantsthatoriginatedfromacommonancestorandmaintainthecharacteristicsoftheancestor)fromanindependentsinglecellmultiplication.Therefore,apurecultureofamicroorganismfromdifferentsourcescanbecalledastrainofthestrain.Thestrainemphasizesageneticallypurelineage.Forexample:TwostrainsofEscherichiacoli:EscherichiacoliBandEscherichiacoliK12

Strainnotation:Ifthespeciesisthebasicunitoftaxonomy,thenthestrainisactuallythebasicunitofapplication,becausethesameDifferentstrainsofstrainswillhavegreatdifferencesanddifferencesinthetypesofenzymesortheyieldsofmetabolites!②Subspeciesorvarieties:reclassificationwithinspecies.

Whendifferentstrainswithinacertainspecieshaveafewobviousandstablevariationcharacteristicsorgenetictraits,buttheyarenotenoughtodifferentiateintonewspecies,thesestrainscanbesubdividedintotwoormoreSmalltaxa-subspecies.

Varietyissynonymouswithsubspecies.Becausetheword"variety"caneasilycauseconfusioninthemeaningoftheword,theterm"variety"hasnotbeenusedsince1976.Themutantstrainsobtainedinthelaboratoryareusuallycalledsubspecies.

Forexample:E.colik12(wildtype)doesnotrequirespecialaa,andafterlaboratorymutation,adefectivetypeofaacanbeobtainedfromk12,whichiscalledasubspeciesofE.colik12.③Form:oftenreferstothesubdivisionbelowsubspecies.Whenthetraitdifferencesbetweendifferentstrainswithinthesamespeciesorthesamesubspeciesarenotenoughtobeclassifiedintonewsubspecies,theycanbesubdividedintodifferenttypes.Forexample:Accordingtothedifferenceofantigeniccharacteristics,itisdividedintodifferentserotypes.

Nomenclatureofmicroorganisms:Therearetwokindsofnamesofmicroorganisms:commonnamesandscientificnames.Suchas:redbreadmold-Neurosporacrassa;Pseudomonasaeruginosa-Pseudomonasaeruginosa.Scientificname-thescientificnameofmicroorganisms,itisnamedinaccordancewiththerulesdrawnupbytheInternationalCommitteeonClassificationofMicroorganisms.ThescientificnameiscomposedofLatinwordsorLatinizedforeignwords.Therearetwomethodsfornamingscientificnames,thedouble-namemethodandthetriple-namemethod.①Doublenamemethod:scientificname=genusname+speciesname+(firstnamedcelebrity)+currentcelebrity+namedyearGenericname:Latinnounsoradjectivesusedasnouns,singular,capitalizedfirstletter,indicatingthemaincharacteristicsofmicroorganisms,Constructedbymicroorganisms,shapesornamedbyscientists.Speciesname:Latinadjectiveswithlowercaseinitials,whicharesecondarycharacteristicsofmicroorganisms,suchasmicrobialpigment,shape,source,orscientist'sname,etc.Example:Escherichiacoli(Migula)CastellanietChalmers1919

StaphylococcusaureusRosenbach1884Whenreferringtoacertaingenusofmicroorganisms,butnotspecificallyreferringtoacertainspecies(orunspecifiedname)ofthegenus,Youcanaddsp.orssp.(representingthesingularandpluralformsofspeciesabbreviations)afterthegenusname.

Forexample:Saccharomycessp.RepresentsaspeciesinthegenusSaccharomyces.Strainname:Addnumbers,placenamesorsymbolsafterthespeciesname.Forexample:BacillussubtilisAS1.389AS=AcademiaSinica

BacillussubtilisBF7658BF=Beifang

ClostridiumacetobutylicumATCC824ClostridiumacetobutylicumATCC824>

ATCC=AmericanTypeCultureCollectionAmericanTypeCultureCollection

Whenascientificnamehasappearedbeforeinthearticle,thegenusnamecanbeabbreviatedinto1~3lettersintheback.

Forexample:EscherichiacolicanbeabbreviatedtoE.coli

StaphylococcusaureuscanbeabbreviatedtoS.aureus②Threenamingmethods:usedtonamesubspecies,atthistimeinthegenusandspeciesnameAddasubsp.afterit,andthenaddthesubspeciesname(italics).Forexample:Bacillusthuringiensissubsp.galleriaBacillusthuringiensissubsp.Grifola