页数：127页文件大小：25.18 MB来源： 微生物学ppt课件
本课件为英文版原核微生物章节，介绍细菌的形态与大小，逐层解析细胞壁、细胞膜、核区、糖被、鞭毛、菌毛与芽孢等结构，比较革兰氏阳性与阴性菌细胞壁成分，并介绍放线菌、支原体、立克次氏体、衣原体、螺旋体与蓝细菌。
Chapter 2 Prokaryotic Microorganisms
PurposePredominatebasic concepts of theprokaryotic microorganism.Study the basic form, cell structure,reproduction method and culturalcharacteristics of primary prokaryoticmicroorganisms.Comprehendthe close relation between eachkind of prokaryotic microorganism andhumanity production and our life.
What is the prokaryotic microorganism?It isan single-celled organismwhich doesn’t have anuclear membraneoutside the cell nucleus and only has the bare DNA called as the nuclear area. It is entitled the generalized bacterium.Main sorts of the prokaryotic microorganism ：According to shape characteristic: bacteria (narrow sense),actinomycete ,cyanobacteria ,mycoplasma ,rickettsia ,chlamydia and spirochete.According to physiological and biochemical Indices and molecular biological characteristics :true bacteria and Archaeum
Section 1 BacteriaBacteria (narrow sense) is a kind of procaryote. Its special characters are that thin and short cell, simple structure, tough cell wall, fissiparity of two parts and stronger hydrophily trait.
Bactericlocations:aerosphere、water、soil、inthebodyofpropagationBactericbreedandquantity:variouskinds,highnumbersTheinfluenceofbacteriatohumansociety:1. harmful influence: it’s a kind of propagation pathogens which cause the putrescence of food and goods.2.wholesome effect: the manufacture of bacteria zymolytic products,agro-biological pesticide ,the product of bacterial manure, bacterial leaching , microbial preparation, sewage management and so on.
I. Modality and bulk of bacteria（1）Modality of bacteriaBasic form of bacteria unit:globularity、rod shapeand twist
(a) monococcus (b) diplococcus (c) tetracoccus (d) sarcina (e) staphylococcus (f) streptococcus Different shapes coccusDifferent shapes bacilus(a) coccobacillus (b) single bacilus(c) diplobacillus (d) streptobacillusDifferent shapes spirochete(a) spirillum (b) leptospira (c) vibrio
cocci
bacillispirillum
Special types of bacteria
（2）bacterialsizeMostofthebacterialcelldiameterisabout0.5mm,andthelengthisabout0.5~5mm.However,reportedthediameterofthesmallestnanobacteriaislessthan0.05mm.ThelargestcoccusisThiomargaritanamibia，whosediametersizeisupto100-750μm.
model construction of bacterial cell2. Cell structure
Structure of cell wall about gram-positive bacteria and gram-negative bacteria Types of cell wall：cell wall of gram-positive bacteriacell wall of gram-negative bacteria
1.Cell wall structure of gram-positive bacteriacharacteristic：thickness of cell wall is bigbetween 20~80 nm.Chemical composition is simple, which contains 90 percentpeptidoglycanand 10 percent Lipoteichoic acid.
(1)TitaniumPolysacchari:PeptidePolysaccharidiscomposedofnetworkmoleculesformedbytheshortpeptidesthatonePassinganother.Itistheownelementofcellularwall,anditconstructsthehardframeworkofthecellularwall.短肽交联Polysaccharid chain
n（M）（G）the monomerillustrateof Gram bacteria (+)cellular wall peptidePolysaccharideleft: the connection among simplified monomermolecules；Right：the constuctionof simplified monomer arrowhead stands for the pot of bacteriolysis enzymehydrolyze
The main 4 types ofpeptidebridge in peptidePolysaccharid moleculestype the connecting point of the end ofA peptidepeptide bridgethe connecting point of B peptideeg.I 4thamino acid-CO.NH-connected directly 3th amino acidE. coli(G-)II 4th amino acid-(Gly)53th amino acidS. aureus (G+)III 4th amino acid-(the end of pepitide)1~2-3th amino acidM. luteus(G+)IV 4th amino acid-D-Lys-2th amino acidC. poinsettiae(G+)
（2）Teichoicacidteichoicacidisakindofacidpolysaccharide,whichcombineswithbacteriacellularwallofGrambacteria(+).It’soneoftheGrambacteria(+)bacteriasownelements.The structure pattern of glycerinteichoic acid（left）and monomer(right)
The type of teichoic acid：Acrording to the elements ofPolysaccharid：glycerinteichoic acidribose methyl teichoic acidAcrording to the type of conbining molecules with the wall and the distribution:Wall teichoic acidLipoteichoic acid
2.ThecellwallstructureofG-:Characteristic：thelayerofpeptidepolysaccharidisverythin(only2~3nm).thereisanotherthecaoutsidethelayerofpeptidepolysaccharidanditscomponentsiscomplex.ThewallplyofG-isthinnerthanG+anditsmechanicalintensityisfrailerthanG+’s
G-exosporium
Lipopolysaccharide (LPS)structure of lipoid A in salmonella lipopolysaccharide
3.Gram staining
Composition gram positive bacteriagram negtive bacteriagram stain reactionPeptidoglycanContentStructureCell wallThicknessLayer arrangementteichoic acidlipopolysaccharideandlipoidlipoproteinSensitivity topenicillin and sulfanilamideAnd the relation to membranebacteria take on purpleHigh, 30-95% of solid bacteriaMultilayers and compact20-80nm,monolayerExists in most cases, high in content(<50)None in most casesNone in most casessensitiveSensitivelooseBacteria take on red after being decolored and restainedLow, 5-20% of the solid bacteriaMono or double lays loose~10nm (8nm of theout membrane),multilayersnoneHigh content（mainly in outmembrane）High content（mainly in outmembrane）insensitiveinsensitiveCompactTable:The comparison of cell wall composition between gram positive bacteria and gram negative bacteria
4. Defection of cell wallSeveraltypesofdefectivecellwallornoncellwallbacteria：a.Protoplastreferstotheleftcellonlycoatedbycellmembraneafterclearinginherecellwallbylysozymeorrestrainingsynthesisofcellwallbypenicillin,whichisoftenseeninGram-positivebacteria;b.Sphaeroplastreferstotheprotoplasmwhichistheresidueofpartofcellwall,whichisoftenseeninGram-negativebacteria;
③L-formBacteria:L-formBacteriaspecialrefertotransmissibilitystablecellwalldeficientstrains,shapedbyitsnaturalmutantinthelaboratory.In1935,ListerResearchInstituteofpreventiveMedicineinEnglandfoundoutakindofcellwalldeficientbacteria,formedbynaturalmutant.----Streptobacillusmoniliformis.itcellisbig,anditissensitivetotheosmoticpressure,engenderingsmallcoloniesinthesolidculturemedia,likeomelette.becauseofthefirstletterofListerResearchInstituteis“L”,sonamedL-formBacteria.
(2) Cytoplasmic membranecharacteristic:①The cell membrane of prokaryotes commonly not include cholesterol and sterol (except Chlamydia), this is clearly difference from eucaryote. Because Mutil-alkene antibiotic can destroy the cell membrane of sterol, so it can inhibit the mycoplasma and eucaryote. It is, however, not act to other prokaryotic microorganism.②Many gram-positive bacteria can form capsular mesosome by cytoplasm construction-a body, which is fraught with the bedded or fistular vesicles. mesosome have related to the secretion of certain enzymes, such as penicillin enzyme; also probablely related to the DNA replication, distribution and cell division.
Bacillus fastidiosusMesosome
（3）Cytoplasm and inclusion bodyCytoplasm:Thetermcytoplasmreferstoeverythingbetweenthecellmembraneandthenuclearenvelope,includingalltranslucent,jelly-likematerialandgrains.Theclearlydifferencebetweenprokaryoticmicroorganismandeucaryoteisthecytoplasmofprokaryoticmicroorganismcannotfloat.Cytoplasmcomposition:Water:about 80%Ribosome:(consist of 50S subunit and 30S subunit)Various compounds:such asstromal ingredient, intermediate metabolite, nourishing substance, large molecule and so on .inclusion body:such as thylakoid, carboxysome, gasvesicle(or parasporal body) and so on. (the larger shapegranular construction called inclusion in cytoplasm, including various stock and carboxysome, gasvesicle and so on .
Poly-b-hydroxybutyrate( PHB）：it is a kind of carbon source storage , which pertain to adipoid property, it plays role of store capacity, carbon source and reduce cell osmotic pressure. As biological polymers, it has bright future of application.
Polyphosphategranules(PP）：becauseitcanbedyedmagentabymethyleneblueor甲本胺蓝,soitknownasmetachromaticgranules.Componentsforthekeysareorthophosphoricacidlinearpolymermonomerlinkedbyesters,itplaysanimportantpartinstoringphosphorus,energycapacityandreducingcellosmoticpressure.
c. Carboxysome lies in polygon or hexagon inclusions of some autotrophic bacterial cells containing 1,5 ribulose bisphosphate carboxylase, where autotrophic bacterial fix carbon dioxide, and which lies in Thiobacillus, Beggiatoa, nitrobacteria and somecyanobacteria.Carboxysome of thiobacilli is showed in the picture.羧酶体
④Gas vacuoles (blue) and storage granules (red) in the cyanobacterium MicrocystisThe formation of gas vacuoles by aquatic bacteria provides a mechanism for adjusting the buoyancy of the cell.Many aquatic cyanobacteria use their gas vacuoles to move up and down in the water column.
(D)Nuclearregion（prokaryon,nucleoid）nuclearregionreferstothespecialnonnuclear-membranestructureofprokaryoteandthenon-fixingmorphologyoriginalnucleus.
(E)GlycocalyxGlycocalyxisstickysubstancesecretedbysomebacteriaunderacertainnutritionalcondition,whichiscoatedonthesurfaceofcellwallwithvariablethickness.
（b）（d）（a）Glycocalyx slime （b）SlimeLayer (c) fluorescence microphoto (d) capsule（a）（c）
Typesofglycocalyx：a.Withimmobilelayercoatedonsinglecellwallcapsulemicrocapsuleslimelayerb.Withseveralcellsoragroupofcellscoatedzoogloca
Major constituent of glycocalyx：polysaccharide, polypeptide or protein，especially polysaccharide Functionofglycocalyx：a.protectiveaction：Lotsofpolarionogensofitcanprotectthallusfromdamagingbydroughtorabsorbingandcrackingbybacteriophage;somecapsulesofanimalpathogenicbacteriacanalsoprotectthemfromphagocytizingbyhostleukocyte,forexample,capsuleofKlebsiellapneumoniaecannotonlyadherehuman’spneogasterandfixplanting,butalsopreventphagocytizingofleucocyte;b.preservecarbonsourceandenergesourcetobereadyforreusingwhennutritiondeficiency;c.aspermeabilitybarrieror(and)ionexchangesystemtopreventbacteriafrompoisoningofheavy-metalion;d.surfaceadhesionaction,forexample,Streptococcussalivariuswhichcanbringdecayedtoothwillsecreteakindoftranshexosylasetochangesugarintolevans,andmakebacteriastickfirmlyonthesurfaceofteeth,whichwillcorrodesubstantiaadamantinaofteethandresultindecayedtooth;e.informationidentificationbetweenbacteria;f.productmetabolismwaste.
(F) Flagellum (pl. flagella)Flagellum is the filament and sinuate proteinaceous appurtenance which grows on the surface of bacterial. A bacterium has 1—10 flagella which have motor function. Flagellum is about 15~20µmlong and 0.01~0.02µm in diameter.
1. Four basic types of flagellar arrangementsa,monotrichousb,amphitrichousc,lophotrichousd,peritrichous
Flagella are arranged differently on different bacteria. In polar flagellation the flagella are attached at one or both ends of the cell. Occasionally a tuft (group) of flagella may arise at one end of the cell, an arrangement called lophotrichous. In peritrichous flagellation the flagella are inserted at many places around the cell surface (peri means "around"). The type of flagellation, polar or peritrichous, is often used as a characteristic in the classification of bacteria.
2.Flagellate general structureThe flagellum of a Gram-negative bacterium
The filament of bacterial flagella is composed of subunits of a protein called flagellin.The base of the flagellum is different in structure from that of the filament. There is a wider region at the base of the flagellum called the hook. The hook consists of a single type of protein and functions to connect the filament to the motor portion of the flagellum.The basal body is anchored in the cytoplasmic membrane and cell wall. The basal body consists of a small central rod that passes through a system of rings.
In gram-negative Bacteria, an outer ring is anchored in the lipopolysaccharide layer and another in the peptidoglycan layer of the cell wall, and an inner ring is located within the cytoplasmic membrane.In gram-positive Bacteria, which lack the outer lipopolysaccharide layer, only the inner pair of rings is present. Surrounding the inner ring and anchored in the cytoplasmic membrane are a pair of proteins called Mot . These proteins actually drive the flagellar motor causing a torque that rotates the filament. A final set of proteins, called the Fli proteins function as the motor switch, reversing rotation of the flagella in response to intracellular signals.
3.Mechanism of flagellar movement“ rotation theory”
4.FlagellatefunctionManyprokaryotesaremotile,andthisabilitytomoveindependentlyisusuallyduetoaspecialstructure,theflagellum(plural,flagella).
(H)Specialdormantstructure--sporeSomebacteriacanformaroundedorovalrestingstructurewhichhasthickwall,lowwatercontentandstrongstresstoleranceinthelategrowthanddevelopmentstage,whichiscalledsporeorEndpspore.Dominant species ：Bacillusand Clostridium
1. Characteristics of sporea.Spore is resting structure instead of propagative structureb. Spore has strong stress tolerance.c. Dormant ability of spore is very strong.
2. Schematic diagram of sporular structureSpore coatCortexSpore wallSpore membraneSpore cytoplastSpore nucleus sectionSpore extexineSpore coat
3. Sporulate process
4. Heat-resistance molecular mechanism of sporea.Cortex expansion osmoregulation theroyb. Dipicolinic acid （DPA）theroy
5.ParasporalcrystalFewbacillus,suchasBacillusthurgiensiswillproducearhombicorbiconicalkalisolubleproteincrystal—δendotoxinnearnewspore,whichiscalledparasporalcrystal.Itsdryweightcanbe30%ofsporangiumweight,anditconsistsofeighteenaminoacids。
Thiskindofbacteriaproducingparasporalcrystalcanbemadebioticpesticide--bacterialinsecticidewhichisinfavorofenvironmentalprotection,becauseparasporalcrystalcanpoisionmorethan200kindsinsectsespeciallylepidopteralarvage.
6. Other resting structure--cystCystisakindroundedsiccocolous,noheat-resistanthypopuswhichisformedwhenazotobacteriaespeciallyazotobactervinelandilackofnutritiousbecauseofnutrientcellularextineaccretionandcellulardehydration.Anutrientcellishypopusasspores,becauseitcanformacystonly.Cystcanbudandgrowvegetativelyunderfeasibleenvironment.
III. Reproduction and cultural characteristics of bacteria
（A）Reproduction of bacteriaMethod of production is generalVegetative propagation.Major method of production：binary fissionFew method：ternary fission ( e.g. sulfur bacteria)multiple fission (e.g. minitype campylodromous bacteria )budding ( budding bacillus)
binary fission of bacillusTernary fission of 格形暗网菌multiple fission of Bdellovibrio
(B) . Cultural characteristics of bacteriaCulturalcharacteristicsrefertocolonialgrowingmorphologicalcharacteristicsofbacteriainsolid,semisolidandliquidmedium.Bacteriahavetheirintrinsicculturalcharacteristics.
1.Solid cultural characteristics of bacteriaColonyisamacroscopicgroupformedbyabacteriumorsporeinthesolidmedium.Colonialcharacteristics:Itishumid，smooth,transparent,ropy,easilytopickupandeven,andithassamecoloronpositiveornegativesurface,edgeorcenter.Significance:Itisoneofindicationsofclassificationanddeterminationofmicrobe.Bacteriallawnreferstomuchflakymacroscopicofcolonyformedbymanybacteriaorspores’reproductioninthesolidmedium.
2.SemisolidculturalcharacteristicsofbacteriaSemisolid medium：containing 0.35-0.4% agarPunchinoculationPurpose：toobservetheirmotilityandwhetherbacteriawilldiffuseandcontainflafellum.3.LiquidculturalcharacteristicsofbacteriaTheyoftenpresentturbidandseldomformdepositionandpellicle.
A.Characteristics of actinomyces1.What is actinomyce？Actinomyceisakindofmyceliumwithbranchesandfilamentousbacteriumreproducingbyspores.2.Whydoesitbelongtoprokaryote?a.Myceliumofitisunicell,whichisthinnerthanfungoidandclosetobacteria;b.Withoutnuclearmembrane,nucleolusandmitochondriaetc.,itbelongstoprokaryotewith70Sribosome;c.Cellwallscontainmuramicacid,diaminopimelicacid,butdon’tcontainchitinandcellulose,andGramstainingismasculine；d.EnvironmentalPHcouldbenearneutralortendingtoalkali,whichissimilartobacteria,butdifferentfromfungi(tendingtoacidity)；e.Antibioticswhichcanrestrainbacteriacanalsorestrainactinomycetes,whileantibioticswhichcanrestrainfungicannotrestrainactinomyces；f.Itissensitivetolysozyme.Section 2 Actinomyces
Chain of conidiosporesAgar surfaceSubstrate myceliumAerial hyphaeThe cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiosporesVarious types of spore-bearing structures on the streptomyces
B. Morphology and structure of actinomycete---actinomycete of Streptomyces1. Morphology and structure of streptomycete thallussporularhyphaespore aerial hyphae surface of medium substrate mycelium
Chain of conidiosporesAgar surfaceSubstrate myceliumAerial hyphaeThe cross section of an actinomycete colony showing the substrate mycelium and aerial mycelium with chains of conidiospores
a.Substratemycelium(vegetativehypha,primarymycelium)reptateinoronthesurfaceofmedium.Absorbingnourishingsubstanceanddrainingwastesofmetabolismareitsprimaryfunctions.Ithasnotdiaphragmsexceptnocardin,whichhas0.2-1.2μmdiametersandgreatdifferencelengths(100-600μm).Itpresentsachromaticorallthecolorsofyellow,green,orange,red,purple,blue,brownorblackbecauseofproducingwatersolubleorfatsolublepigmentsb.Aerialhyphae(secondarymycelium)issubstratemyceliumoutgrowingspacewardwhenitdevelopstoacertainstage,whichisoftendarkandfatterthansubstratemyceliumin1-1.4μmdiameter,andwhichisstraightorbendingwithbranchesandgreatlydifferentlengths.
c.Sporularhypha(breedinghypha,gonimoblast)wouldformafterdifferentiationofaerialhyphaewhenitgrowstoacertainstage.TheshapeandtacticmodeofSporularhyphaisdifferentaccordingtoitsspecies,somearestraightandsomeareundulationorvolution,thecounts,spacingdegreeandrotationsenseofwhichisthecharacteristicsofspicies.Type-scheme diagram of sporular hypha of actinomycete
Various types of spore-bearing structures on the streptomycesStreptomycesspores, called conidia, are not related in any way to the endospores of Bacillus and Clostridium because the streptomycete spores are produced simply by the formation of cross-walls in the multinucleate sporophores followed by separation of the individual cells directly into spores.
d. Sporeof actinmycete could be spherical, oval, rod and column etc. . The shapes and sizes of same sporular hypha are different sometimes. As a result, species could not be distinguished by the shapes and sizes only. The structural difference of spore surface could be seen with electron microscope, some surfaces are smoothing , some have miliary tubercles, spines or filiform. Spore is often gray, white, yellow orange, blue and green, and the color it is very stable under some medium and culturing condition. Surface structure and color of spores are one of main references in identifying actinomycetes species.Structural pattern diagram of sporular form and surface texturing of actinomycetes
2. Morphology and structure of otheractinomycetes
C. Reproduction of actinomycetes1. ConidiumWhen actinomycetes grow to a certain stage, some aerial hyphaes form spore fiber，which differentiate to many conidiophores. of Spores are produced by two septum splitup modes.(a) Invaginate of cytoplasmic membrane；(b) Invaginate of cytoplasmic membrane and cell walls
2. Sporangiospore Some actinomycetes form cysts from curl hypha, and septums and spores produce between cysts. After maturation, cysts give off cystozoite. It can be formed on aerial hyphae or substrate mycelium.Forming process of 链孢霉孢子囊形成过程(a) The initial forming stage of sporangium；(b) regrowing of sporagium and forming of septum inside；(c) mature sporangium and disordered sporangiospore
SporangiosporeSporangiospores are formed within a sporangium
Conidiospores
3. Fracture of substrate mycelium when vegetative hyphae maturates, nocardia will come upon bacillar, globular or dendroid conidiospores which have uniform shape and size in crosscutting split.
4. Any hyphal fragmentsActinomycetes can form new mycelium by fractured fragments of hypha, which can be seen in liquid medium. They reproduce a lot in the way during antibiotic production. Pellicle will always form at the surface of medium and spores will push out of pellicle during static culture.
Section 3mycoplasma, rickettsia, chlamydia
I. MycoplasmaMycoplasmaaretheprocaryoticorganismbetweenbacteriaandrickettsia.Theyarenaturallylackacellwall,andoftentakeonramoseprotonemawhensubmergedcultured,sotheyarecalledmycoplasma.The mycoplasma which was first isolated named pleuropneumonia mycoplasma , for it was from the cattle suffered from pleuropneumonia .It was found in 1967 that mycoplasma were also exist in the phloem of many plants such as mulberry and potato which suffered from hexenbesen. In order to distinguish with the mycoplasma infect animal, mycoplasma which infect plate are usually called “mycoplasma-like organism”.The biological meaning of mycoplasma are: many mycoplasma cause diseases of animals such as cattle, sheep, goat, pig, birds and human; some mycoplasma cause botanic diseases; often pollute tissue culture in laboratory because of their filtration permeability.
1.ConfigurationandSizeCellsofmycoplasmaareverysmall,theyareeyeableconstrainedlyunderopticalmicroscope.Theirdiameterareprobably150～300nm,usuallyabout250nm,somycoplasmacouldpermeatebacterialcolander.Mycoplasmaweredeemedtobetheleastautotrophinthewholebiologicaluniverse,beforenanobacteriawhichareonly50～200nmwerefounded.cellsofmycoplasmaarepolymorphous,variabilityandassumeasfiliformandcladodromouswithglobosityordifferlengthImages of Mycoplasma pneumoniae,Show their polymorphism.（a）TEM image（X47，880）;（b）SEM image（X26，000）.
2.CytoarchitectureMycoplasmaarelackacellwall,cellsarepliability,Gram-negative,sensitivetoosmoticpressure,sensitivetosurfactantandalcoholsubstance,notsensitivetotheantibioticssuchaspenicillin,cycloserinewhichcouldinhibitthesynthesisofcellwall.Cytolemmacontaincholesterin,isquitesensitivetopolyenicantibioticssuchasamphotericinandfungicidin.Cytolemmaisalsoquitesensitivetosurfactantwhichdestroycytolemmastructureandliposolublesubstance.Thegenomeofmycoplasmaisverysmall,onlyabout0.6～1.1MbConfigurable characteristic1）Cytolemma contain sterol2）lack of cell wall，not sensitive to the antibiotics which inhibit the synthesis of cell wall3）“fried egg colony”4）genome is small，0.6~1.1Mb5）binary fission and gemmation
3.CharacterofpropagationandcultureMycoplasmausuallypropagationbythewayofbinaryfissionMycoplasmaareparasitismorpythogenesis,couldgrowineutrophicmediawhichcontainserum,yeastextractionorsteroletc.Characterofcolony:colonyissmall,diameterusuallyisonly0.1～1mm,takeonitsown“friedegg”shape.Characterofsubmergedculture:noturbidity.“fried egg”shape
II.RickettsiaIn1909,aAmericandoctorH.T.Ricketts（1871～1910）firstfoundthepathogenoftyphusanddiedofthisdiseasein1910.Becausethegenusofmicrobeareobligatoryparasitismandcouldnotbeartificiallycultured,andinordertocommemoratethediscoverer,thegenusofpathogenarecalledrickettsia.Since1972manymicrobeswhichwerelikerickettsiahadbeenfoundfromphloemofsomesickenplant.Inordertodistinguishwithrickettsiawhichparasitizeinzooblast,theywerenamed“rickettsia-likeorganism”Biologicalmeaning:arepathogenofhumanseverezymosissuchas:typhus,tsutsugamushifeverandQfeveretc.Mainlycausehumandeathbyproduceendotoxin.
1）G-，parasitism（have cell wall，could not life independently, cell is big 0.3-2 µm）2）Sensitive to heat, could be killed up 56℃ for 30min，sensitive to antibiotics such as tetracycline, penicillin and etc.3）Propagate by binary fission，their parasitifer commonly are arthropod，and could inroad into body from wound. 4）Genome is small: 1.1Mb.5）Pathogenicity：propagate largely in blood of parasitifer，and produce endotoxin.Characteristic
rickettsia1.Configuration and SizeThebulkofcellis0.3～0.6μm×0.8～2μm.Thesizeissimilartogenericbacteria，butlargerthanmycoplasmaandchlamydia，havenofiltrationpermeability.Theshapeofcellismultiplicity,usuallytakeonsphericity,rodshapeorfiliform.
2.CytoarchitectureRickettsiahavecellwall,Gram-negative.Itscellwallcontainsmuramicacidanddiaminopimelicacid.Inaddition,Itscellwallcontainslipopolysaccharidecomplexwhichissimilartobacterialendotoxin,butitslipidcontentisoutclasscommonbacteria.Becausethecytolemmaofrickettsiaisloose,theosmolarityisrelativelylarge.Thispermeabilitycytolemmaallowrickettsiaeasilyobtainsomeimportantsubstance(includecoenzymessuchasNAD+andcoenzymeA)fromparasitifer,meanwhile,someimportantsubstancealsoeasilydepartfromrickettsia.Genomeofrickettsiaisquitesmall,forexample:thegenomeofRickettsiaprowazekiisonly1.1Mb,containsonly834genes.
3. ResistivityRickettsia are sensitive to heat, could be killed up 56℃for 30min. Rickettsia are sensitive to many antibiotics which resist bacteria such as tetracycline, penicillin and etc.4. Metabolic systemExist energesis system, but lack intact energesis metabolic pathway. Rickettsia could not oxidateglucose or organic acid, they could only oxidate glutamic acid and glutamine to generate energy, so rickettsia would go dead when leave parasitifer.
Rickettsiausuallypropagationbythewayofbinaryfission.Theyarestrictintracellularparasitismwhichissimilartovirus.Themajorityofrickettsiacouldnotbeculturedbyartificialmedia,itisneedtouseyolkbagofchichenembryo,histiocyteofsensitiveanimal,andsensitivelaboratoryanimaltodosecondaryculture.Rickettsianeedhaematophagousarthropodsuchasflea,acaridasthevectorintheirlifecycletopassagebetweenanimals,sorickettsiaarealsocalled“entomophilousmicrobe”.5. Character of propagation and culture
III. ChlamydiaChlamydiaareagenusofminitypeGram-negativeprokaryoticorganismwhichobligateparasitizeineukaryoticcells.Theyarecalled“energyparasitism”becausetheyneedATPfromparasitiferforhavenoenergesissystem,sochlamydiahadbeendeemedtobe“largevirus”foralongtime.ChlamydiaaregraduallyproventobeagenusofspecialorganismwithcytoarchitecturesinceprofessorTangfei-fangseparatedpathogenfromtrachomain1956.Primarybiologicalmeaning:Chlamydiapsittacosiswhichcausezoonosessuchaspsittacosisandetc.,Chlamydiatrachomatiswhichcausehumantrachoma,Chlamydiapneumoniaewhichcausepneumonia.
1. Configuration and SizeChlamydiahavetwokindsofcellularconfigurations:onekindisextracellularofparasitifer,namedprotomerwhichtakeonsphericity(diameterissmallerthan0.4μm)andhaveinfectivity;anotherkindisindwellinendocellularofparasitifer,namedinitialbodyorfiloplasmodiumwhichtakeonbiggishsphericity(diameter1～1.5μm).
2. Life cycle of Chlamydia
①HavecellwallwiththecharacterofGram-negative,butlackpeptidoglycan;②Havehalf-bakedenzymesystem,especiallylackenergesismetabolicenzymesystem;③Besensitivetoantibioticandmedicationwhichinhibitgrowthofbacteria,butarenotsensitivetopenicillin,Chlamydiapsittacosishastheresistivitytosulfanilamide;④Lifestyleisstrictlyobligateendocellularparasitism.Inlaboratory,Chlamydiacouldbeculturedinyolkbagmembraneofchickenembryo,abdominalcavityoflittlewhiterat,tissueculturecells,orHeLacells;⑤Havespeciallifecycleandtwoconfiguration,couldformendocellularocclusionbodyofparasitifer.3. Character of Chlamydia
Section 4 SpirochaetaSpirochaeta are a group of Gram-negative unicellular prokaryotic organismwhose configuration and kinesiology are particular.Spirochaeta were classified to animal because their cells are slightness and pliancy ,and could make special bend twist or move like snake.
1. Configuration and Size of SpirochaetaCells are gracile, take on twist and have no flagellum. The size of Spirochaeta is 0.1~3.0X3~500mm.
2. Conformationof Spirochaeta: protoplasmic columniation, axial fiber, epitheca
3. Biological meaningSpirochaeta are indwell water and animal. The contagious venereal disease syphilis is caused by Treponema pallidum.
Section 5 CyanobacteriaCyanobacteriaaresimilarwithPlantinsomeaspects,Suchas,theybothcontainchlorophyllaandphotosynthesisⅡ,andhavephotosynthesiswithoxygen,wereregardedasplantforalongtime.Sotheywerecalledbluealgae.Butinfact,Cyanobacteriaaredifferentfromalgaeinmanyways.Cyanobacteriadonothavechloroplastandeukaryon,have70Sribosome,therearepeptidepolysaccharideintheircellwall.Theyaresensitivewithpenicillinandlysozyme.SoCyanobacteriawaswipedinbacteria.Cyanobacteriadifferfromphotosyntheticbacteriawhicharebelongedtorhodospirillales,thelatterprocessquitecrudercyclicphotophosphorylation,anddonotgiveoutoxygen,werecalledanaerobe.
1.MorphologyandSizeThesizeofCyanobacteriacellisbiggerthanthebacteria,isoften3~10μm，butsomeisalsobigas60μm.Theyhavevarietyofmorphology,singlecellformasballorrodshape,manycellsformasfiliform,braidfiliformortwist,somehaveheterocyst.
2. Cellularity of Cyanobacteria
3.HeterocystandAkinete1)HeterocystNitrogenFixationFunction2)AkineteDormancyFunction异形胞((H)和静息孢子(A)
5.BiologicalsignificanceofCyanobacteria1）Contributiononbiologicalevolutionhistory:Cyanobacteriaareaerobicbacteriawhichliveinpond,lake,river,seaandsoon,arearchaicprokaryotewithnumerousandjumbledspecies,theymadesignificantforbiologicalevolutionintheearthphylogeny,becausetheirdevelopmentmadetheearthsatmospherefromnon-oxygenstatetooxygenstate.Cyanobacteria distribute widely in a variety of water and soil. They can symbiosis with some plant, as leaf cavity of Azolla and root of Cycas and Gunnera. They have high resistance to poor condition and general nitrogen-fixing capacity, so they have a good name of “Pioneering Organism”
3）Some Cyanobacteria cause red tide and water bloom which can pollute the lakes
Section 6 The ArchaeobateriaTheArchaeobateriaareacrowdofsinglecellnucleusbiologywhichhasauniquegenestructureorthesystemgrowthbiologymacro-moleculesequence,livewiththeextremehabitatortheenvironmentperiodofthelifeinitialontheEarth,liveonself-supportiveorother-supportivelife;Hasthespecialphysiologicalfunction,liveintheenvironmentofsuperhightemperature,thehighpotentialofhydrogen,highconsistenceofsaltandnon-oxygencondition;Hastheuniquecellstructure,asthecellwallskeletonisproteinorthevacationbutcherwallacid,andthecellmembranecontainstheglycerineetherlinkage;Aswellasinmetabolismenzymeactionwaybothisdifferentwiththebacteriumandisdifferentwiththereallynuclearbiology.
Somebacteriawhichcanproducethemethane:(a)Henrymethanespirillum;(b)Shimethanebacillusbrevis;(c)Pakistanmethanesarcina;(d)Mazemethanesarcina;(e)clothMethanebacillus;(f)BlackSeamethanebagshapefungusI. Morphology of Archaeobateria (ancient bacterium)
The type of ancient bacterium cell wall structure
The structure of false peptide polyose In methane bacilli cell wall
The spinyFour hydrogen spiny(1) in the phosphatide the sparse water tail has the special long chain hydrocarbon composition2. Cell membrane
(2)Glycerineandhydrocarbonareconnectedwithspecialetherlinkage.
(3) Exist the unique monolayer membrane ,or the monolayer , the double molecular mix membrane.
(1)ribosebody:Thesizeis70S,butitsstructureissimilartothe80Sribosebody,its16StherRNAnucleotideorderisunique,eitherdifferentwiththerealbacterium,ordifferentwiththereallynuclearbiology.(2)tRNAingredient:Itsnucleotideorderisalsospecial,anddoesnothavethethymine.ThemajoritykindshiftsinRNAthatnottocontainthedihydrouracil.(3)proteinsynthesisoutsetpassword:Beginswiththemethionine,thesameasreallynuclearbiology.(4)Thesensitivityonantibiotic:Tothesefunctionsintherealbacteriumcellwallantibioticlikepenicillin,thesporemildewelementandtheD-cycloserineandsoonisinsensitive;Hastheinhibitoryactiontotherealbacteriumtranslationthechloromycetinnottobeinsensitive;Hastheinhibitoryactiontothereallynuclearbiologicaltranslationthediphtheriatoxinextremelytobeactuallysensitive.Inadditiontheancientfungusissensitivetotheanisemildewelementbutalsohastothecardthatmildewelementinsensitivecharacteristicwiththerealbacteriumleaves.3. Special biochemistry composition
4.TheuniqueecologicalconditionUndertheextremespecialecologicalenvironment,somearethestrictanaerobes,somearetheextremelyaddictedtosaltybacterium,theotherisaddictedtothehotlyandsourbacterium.
III. The main species group of ancient bacteriumAncientbacteriumcanbedivideinto5speciesgroups:1.Producesthemethaneancientbacterium2.Thereturntooriginalstatesulfateancientbacterium3.Theextremeisancientaddictedtothesaltancientbacterium4.Ultraaddictedtohotlyancientbacterium5.Heatsourcebody
Section 7 Classification and the main speciesSergey'sManualofDeterminativeBacteriology，the9theditionofthisManualdivideoriginalnucleusorganismintofourspeciesgroupsbythecharacteristicofcellularwall.Allofthesethespeciesnumberofthin-wall-bacilliandthick-wall-bacilliisthelargest.SpeciesgroupsI：thin-wall-bacilli(Gran.negativebacilli)Group1：Thedarkbacteriumoutline(doesnotcarryonphotosynthesis)Group2：Doesnotproducetheoxygenphotosynthesisbacteriumoutline(photosynthesisbacterium,doesnotproduceoxygen)Group3：Producestheoxygenphotosynthesisbacteriumoutline(photosynthesisbacterium,producesoxygen)speciesgroupsII：thick-wall-bacterium(Gran.masculinebacilli)Group1：ThickwallbacteriumoutlineGroup2：radioactivebacteriumoutlinespeciesgroupsIII:non-wallbacilliGroup1：Thesupplemembranebacteriumoutline(lackscellwallprotoplast)speciesgroupsIV:mendosicutesbacilliGroup1：Ancientbacteriumoutline
Category’s modelModel specific----A typical specific in the CategoryBacillus Bacillus subtilis(Cohn, 1872)Type strain: ATCC 6051=DSM 10=CCTCC AB 92068category’s nameSpecificnameDefine personyearsPreserve institutionAndPreserve IDSpecific epithet
ReferencesPrescottLM,HarleyJP,andKleinDA.,Microbiology(5thed.),HighereducationpressandMcGraw-HillCompanies,Inc.2002MichaelTM,JohnMM,JackP.Brock.,BiologyofMicoorganisms，Internationaledition,PearsonEducation,Inc.2003TalaroK.P.FoundationsinMicrobiology(FifthEdition),HighereducationpressandMcGraw-HillCompanies,Inc.2005ZhouDe-qing，Microbiologytextbook，secondedition，higheducationpublishinghouse，2002
下载地址：{{downurl}}
{{{a}}}
{{#b}}{{{b}}}
{{/b}} {{/title}} {{#nolog}}登陆注册
{{/nolog}} {{#djsx}}点我刷新
{{/djsx}} {{#gocz}} {{/gocz}} {{#ffqr}} {{/ffqr}}