How to isolate the anaerobic bacteria(mixed culture) from soil?could anyone help me?..please....?

Question

How to isolate the anaerobic bacteria(mixed culture) from soil?could anyone help me?..please....?

Answer 1

It is really difficult toestimate the total number of different types of eubacteria,archaeobacteria and virus, as it is very difficult to isolate andrecover the organisms from the environment. Further the naturalenvironment pose varying conditions in different ecosystems ren-dering huge variation among the species existing in main ecosys-tem. Not all environments have been investigated fully and there-fore attempts to estimate total number of species of micro organ-isms become more difficult. In complete understandings of cul-tural conditions required by certain obligate parasites add to thisproblem. Mycoplasma are prokaryotes but have obligate associa-tions with eucaryotic organisms, have remarkable diversity fromsome infecting insects and some infecting plants. The soil,fresh water and marine ecosystems support a group of diverse or-ganisms on their ecosystem providing luxuriant microbial diver-sity.The microorganisms have species that are free living in soiland water, mostly saprophyte in nature, a group that are parasiticon plants and a few others are obligate pathogens of plants, ani-mals and man. Some live in aerobic environment and other liv-ing in anaerobic or microaerophilic conditions. Therefore thereis a wide diversity.The advent of DNA techniques like DNA-DNA hybridiza-tion, nucleic acid finger printing, RNA sequencing has altered the

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Kingdom: ProkaryotaeDivision IGracilicutes Prokaryotes with thinner cell walls, ordinary Gramnegative bacteriaThe Spirochetes:Order: SperochaectalesSpirochaetaceaeSpirochaet... Harmless inhabitants of water, mudand sedimentsCristispira Harmless parasites of molluscsTreponema inhabitants of mouths, intestional andgenital areas of human and animals,some are pathogenic T. Pallidumcauses syphilis in manBorelliaParasites of wild rodentsLeptospiraceaeLeptospira harmless inhabitants of fresh waterEnvironments. L. interoganscauses leptospirosisAerobic/Microaerophilic, motile helical/vibrioid bacteria.Aquaspirillumharmless saprophytes in streams andpondsAzospirillumNitrogen fixing bacteriaOceanospirillumharmless saprophytes of main waterCampylobacterinhabitants of intestines, oral cavityand reproductive organsBdellovibrioParasite on gram negative bacteria6059traditionally based on morphological, biochemical and physiologi-cal characteristics. Serological tests and Genetic tools are valu-able in identification.The general methods of classifying bacteria is by (I) intutivemethod(ii) numerical taxonomy iii. Genetic Relatedness method.While identifying a bacteria morphological, physiological,biochemical general and molecular characteristics of organismsare studied. It may be difficult to classify an organism as differentmicrobiologists may consider different characteristics as impor-tant. This is the intuitive method.Numerical taxonomy gives equal weightage for each char-acter of the strain. The percentage similarly of each strain is deter-mined with the following formula% S = NS / (NS+ND)Where NS: Number of characters for each strain which aresimilar or dissimilarND = Number of characters that are different.,%S, S = Similarly if it is high to each other placed withgroups.In Genetic relatedness classification is based onrelatedness(DNAan RNA) between organisms. The percent G+Cdetermines the relatedness. If two bacteria have a different not %G+C then the species are different and not related. DNA homol-ogy (DNA-DNA hybridization) is also determined to assesses therelatedness. The DNA from a bacterium is isolated and the twostrands are separated and a single strand is mixed with that ob-tained from another. If the two bacteria are similar the pairing ofstrands will occur, otherwise no pairing will occur.

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LegionellaceaeLegionellainhabitant of thermally polluted waterAir conditioning cooling towersNisseriaceaeNisseriaPathogenic to humans, gonorrhea,meningitisFacultatively anaerobic bacteriaEnterobacteriaceaeEscherichia Occur in colon of warm bloodedanimalsShigellacauses bacillary dysentery in humanSalmonellacauses typhoid and paratyphoid,salmonellosisEnterobacter occur in sewage, meatErwiniasoft rot of vegetablesSerratiaoccur in soil, water, plant surfacesopportunistic pathogenProteusoccur in intestine of human, animals;opportunistic pathogenYersiniacausative agent of plaque is Y. pestisVibrionaceaeVibrioaquatic habitate, V. chlorae causescholeraAeromnasaquatic habitate A. salmonicidacauses furunculosis in salmon fish.PasteurellaPasteurella Parasitic on mucous membranes ofupper respiratory tract of mammals.HaemophilusH.influenzae causes meningitis inchildrenActinobacillusOccasionally pathogenic to man6261Non motile(or rarely motile) curved bacteriaSpirosomaYellow pigmentedRunellaPink pigmentedFlectobacillusPink pigmentedMicrocystis intra cellular gas vacuoles presentAerobic rods and cocciPseudomonadaceaePseudomonasinhabita... of soil and water,some are pathogenic to plants,animals, man.XanthomonasPlant pathogens, citrus canker, riceleaf blightZoogloeainhabitant of sewage treatment plantsAzotobactercaceaeAzotobacter free living nitrogen fixerRhizobiaceaeRhizobiumSymbiotic nodule bacteria of legumesBradirhizobiumsymbiotic nodule bacteria of legumesAgrobacteriumPlant pathogens causing gall andtumors.MethylococcaceaeMethylococcusO... methane oxidizersMethylomonasObligate methane oxidizersAcetobacteraceaeAcetobacter acetic acid(vinegar) producersGluconobactersorbose, gluconic acid producer

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The RickettsialesRickettsialesRickettsiaceae... cause trachoma;keratoconjunctivitisThe MycoplasmasClass MollicutesOrder: MycoplasmatalesMycoplasmataceaeMycoplasm... pneumoniae causes primaryatypical pneumonia in humansSpiroplasmataceaeurethritis in human, pneumonia incattleSpiroplasmacauses plant diseaseEndosymbiontsEndosymbionts of protozoa, ciliate, flagellates, amoebaEndosynbionts of insectsEndosymbionts of fungi and invertebrates other thanArthropods.6463Other genera not assigned to any familyZymomonasFerments glucose to ethanolChromobacterium saprophyte of soil and water,infections to human & animals.GardnerellaG.vaginalis causes non-specificvaginitisStreptobacillusA rat parasite S.moniliformiscauses rate bite fever in humans.Anaerobic curved helical rodsBacteroidaceaeBacteroides anaerobic; B. fragilis is associatedwith soft tissue infectionsFusobateriumSuccinomonasWoline... sulphate or sulphur reducing bacteriaDesulfuromonasutilizes elemental sulfurDesulfovibriouse sulphate, thiosulphateDesulfococcususe sulphate, thiosulphateAnaerobic cocciVeillonellaceaeVeillionella inhabitants of oral cavity, respiratorytract, intestinal tract of humans,ruminants. Rodents and pigsAcidaminococcus inhabitants of oral cavity, respiratorytract intestinal tract of humans,ruminants. Rodents and pigsMegasphaerainhabitants of oral cavity, respiratorytract, intestinal tract of humans,ruminants. Rodents and pigs

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Endospore forming rods /cocciBacillusmost species are harmlesssaprophytes of soil andwater; B.anthracis causesanthrax of cattleB.thuringiensis is used asbiopesticide to kill insectsSporosarcinasoil inhabitantAnaerobic spore forming rodsClostridiumdistributed in soil, water andsediments botulism, tetanus arecaused by speciesDesulfotomaculaumoccur in soil, water, intestines ofinsectsNon spore forming rodsLactobacillussaprophytes in fermenting plant andanimal products or parasites ofmouth and intestines of warmblooded animal.ListeriaL.monocytogenes is a pathogen ofanimals and humans, causesmenongitis in adults; pre and postnatal disease in infants.Erysipelothrixparasites of mammals, birds, fish,causes erysipelas in swine,erysipeloid in humansBrocothrixsaprophytes of meat and meatproductsRenibacteriumparasites of salmonid fishes;cause a kidney diseaseKurthiaharmless saprophytes in meat, meatproducts and animal dungCaryophanansaprophytes of ruminant dung6665Division II. Fimicutes(Prokaryotes with thick and strong wall – Gram positive)Grampositive cocciAerobic/FacultativelyAnaerobic cocciDeinococcaceaeDeinococcus :D. radiodurans is a spoilage agent inradiated foods.MicrococcaceaeMicrococcusharmless saprophytes of soil; foundin skin of human and animalsPlanococcusharmless saprophytes of soil;found in skin of human and animalsPlanococcusharmless saprophytes of marineenvironmentsStaphylococcusParasite... on the skin and mucousmembranes of human and warmblooded animals.Aerotolerant Fermentative cocciStreptococcusMost are parasites of human andanimals some ferments sugars tolactic acidLeuconostocharmless saprophytes; forms lactic aacid, used in butter and cheese.Pediococcussaprophytes; form lactic acidAnaerobic cocciPeptococcusoccur in mud, intestines,respiratory tractPeptostreptococcusoccur in human clinical specimensRuminococcusoccur in bovine rumenCaprococcusoccur in human fecesSarcinaoccur in soil, cereal grain, diseasedhuman stomach

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III. TenericutesAnoxygenic phototrophic bacteriaRhodospirillalesRhodospirillacea... non sulfur-bacteriaRhodospseudomonaspurple non sulfur-bacteriaRhodomocrobiampurple non sulfur buddingbacteriaChromatiaceaeChromatiumpu... sulfur bacteriaThiocystispurple sulfur bacteriaThiospirillumpurple sulfur bacteriaLamproocystispurple sulfur bacteriaThiosarcinapurple sulfur bacteriaThiopediapurple sulfur bacteriaChlorobiaceaeChlorobiumGreen sulphur bacteriaProsthecochlorisGreen sulphur bacteriaChloroflexuaceaeChloroflexusGree... non sulphur bacteriaOxygenic phototrophic bacteria(Cyanobacteria Blue Green algaes)The CyanobacteriaChroococcalesPleurocapsales... ProchloralesProchloraceaeProchloronunice... organismscontaining chlorophylb lackProchlorothrix-6867Non spore forming irregular shapesAerobic / Facultatively anaerobicNon filamentous rodsCorynebacterium saprophytes of water, parasites of humans,plant pathogens, C.diphtheriae causesdiptheria in humansArthrobactersaprophytes of soilBrevibacteriumsalt tolerant B.linensMicrobacterium saprophytes in milk and dairy productsCellulomonascellulose degradersAerobic / Facultatively anaerobic branched filamentous rodsAgromycessoil saprophytesArachniapathogenic to human and animals causesactinomycosesRothianormal inhabitant of human mouthAnaerobic nonfilamentious rodsPropionibacterium occur in dairy products, human skin,intestinesEubacteriumoccur in human oral cavity, intestines ofhuman and animalsActinomycesoccur in oral cavity of human and animals;A.bovis causes actinomycosis in cattleBifiidibacterium occur in intestines of human and animalsThe MycobacteriaMycobacteriumpathogens, causes leprosy, tuberculosisThe NocardioformsNocardiasaprophytes of soil and water opportunisticpathogen causing noctrordiosis andactinomycetoma in humans and animalsPsedudonocardia occur in soil and manures

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Prosthecate non budding bacteriaCaulobacteroccur in salt water and fresh waterNon prosthecate budding bacteriaBlastocaulisPlanctomycesoccurs in all aquatic habitatNon prosthecate non budding bacteriaGallinonellacauses clogging in pipelinesof water systemAerobic chemolithotrophic bacteriaNitrobacteraceaeNitrate oxidizing bateriaNitrobacterNitrococcusNitrospiraA... oxidizersNitrosomonasNitrosococcusNitros... and sulphur compounds metabolizing bacteriaThiobacillusoccur in soil, water and coal minedrainsThiomicroscopiraoccur in soil, water and coal minedrainsThiobacteriumMacromonasThiovul... fruiting bacteriaMyxobacterales|Stigmatelladegrad... cellulose, agar, chitinChondromycesdegrade cellulose, agar, chitinGliding non fruiting bacteriaSporocytophagaforms myxospores without fruitingbodiesCapnocytophagaoccur in oral cavity of humansBeggiotiaaquatic environments with H2SCytophagacellulolytic organsFlexibacterVotreoscillaSimonsiella... sheathFlexithrixforms sheathThe Sheathed bacteriaSphaerotilusSheath surrounds a chain of cells ortrichome; iron deposited on sheathLeptothrixHaliscomenobacterStrepto... and or Appendaged bacteriaProsthecate Budding bacteriaHyphomicrobium soil and aquatic environmentsAnclomicrobiumaquatic bacteria form 3-8 prosthecper cell, buds arise from cell

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Extremely halophytic archaeobacteriaHalobacterialesHalobacter... 17-23% NaCl for growth thecells lyse when NaCl falls below10%Halococcusrequire 17-23% NaCl for growth cellslyse when NaCl falls below 10%Halofererequire 17-23% NaCl for growth cellslyse when NaCl falls below 10%ThemoacidiphilesCell wall less ArchaeobacteriaThermoplasmagrows at pH2 and optimumtemperature is 55-59oC cellslyse at neutral pH.Extremely thermophilic sulphate- MetabolizersThermococcalesThermococcacea... pH is 2; temperature is70-87oC7271Iron or manganese oxidizersSiderocapsadeposition of iron or manganeseoxides on slime or capsulesSiderococcusdeposition of iron or manganeseoxides on slime or capsulesSiderocystisdeposition of iron or manganeseoxides on slime or capsulesNaumannielladeposition of iron or manganeseoxides on slime or capsulesArchaeobacteriaMethanogenic archeobacteriaMethanobacterialesMethanob... producersMethenobrevibacterMethane producersMethanomicrobiumMethane producersMethanogeniumMethane producersMethanogeniumMethane producersMethanothermaceaeMethanococcale... sulphate ReducersArchaeoglobalesArchaeglobaceaeAr...

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Taxonomy of FungiThe study of fungi is known as Mycology (Gr.mykes= mush-room + logos=discourse). The term fungus denote nucleated, sporebearing achlorophyllous organisms with filamentous branchedsomatic structure surrounded by cell walls containing cellulose orchitin or both. They reproduce sexually and asexually. However,some true fungi are not filamentous and the filaments of someothers do not have cell walls. Some algae lost the chlorophyll inthe evolutionary process and achlorophyllous but they are not fungi.The cellular slime molds and net slime molds are also studied bymycologists and are not probably fungi.The fungi include moulds, white rusts, downy mildews, pow-dery mildews, sac fungi, black moulds, blue moulds, cup fungi,morels, truffles, rusts, smuts, mushrooms, toadstools, puff balls,stink horn, coral fungi, earth stars, shelf fungi and bird’s nest fungi.They are both beneficial and harmful to mankind. The yeasts areused in leavening of bread, alcohol production as food and feed,for single cell protein and several products are prepared from yeasts.The mushrooms and truffles are cultivated and eaten. White rusts,rusts, smuts, wilts, leaf spot, blight, blast are plant diseases causedby fungi. The Irish famine was caused by potato blight and theBengal famine was caused by Hemminthosporium leaf blight inrice. Most of them occur in soil, decomposing litter, animal dungas saprophytes. There is also a beneficial association between fungiand plants in mycorrhiza (Gr.mykes= mushroom + rizha=root)benefiting both the fungus and plants. The mycorrhizal strandsformed from the root runs far away from root absorbs water,phosphorus, micronutrients etc and supplied to the plants. Thefungus derives its nutrients from the plants. Thus mycorrhiza arecultivated commercially on host roots and given as biofertilizerfor inoculating crop plants. Lichen is an association of fungus andalga knit so close and forming a single thallus. The fungus com-ponent of lichen is called mycobiont and the algal component as7473IV. MendosicutesGram positive filamentous bacteria of complex natureFilamentous bacteria dividing in more than one plateDermatophilusD.congolensis is a parasite ofmammals causing infectionFrankiaNodulating organism in Casuarinaand AlnusFilamentous bacteria forming true sporangiaActinoplanesoccur in dead plant parts, shedanimal hair and soilAmpullariellaoccur in dead plant parts, shedanimal hair and soilSpirillosporaoccur in dead plant parts, shedanimal hair and soilStreptomyces and similar generaSterptomycesdecomposes organic matterstreptomycin antibiotic producerStreptoverticilliumActinopycnidi... bacteria of uncertain taxomomic placentActinomadurasoil saprophytesNocardiopsissoil saprophytesActinopolysporaextreme halophilosm is seenActinosynnemacompact hypha synnemataThermomonosporaoccurs in compost thermophilic andcelluloyticThermoactinomycesoccur in damp hay, composts andmoist grain

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hauster= drinker) that penetrate into the host cells through minutepores punctured into the cell walls or as outgrowth of hyphae andobtain nourishment. Fungi parasitsing on animal tissue are notknown to produce haustoria and fungus grown in culture also donot produce haustoria.The mycelium of most fungi becomes organized into looselyor compactly woven tissues different from ordinary thallus. Theterm Plectenchyma (Gr.pleko= I weare + enchyma= infusion –woven tissue) denotes all organized fungal tissues. Prosenchyma(Gr. pros= toward + enchyma= infusion= approaching a tissue) isloosely woven tissue in which hyphae lie more less parallel to oneanother. Pseudoparenchyma (Gr.psendo= false + parenchyma=aplant tissue) is closely packed more or less isodiametric or ovalcells resembling parenchyma of higher plants. Prosenchyma andthe Pseudoparenchyma compose different types of somatic andreproductive structures like stroma and sclerotium.Two gametangia of opposite s*x come in contact and one ormore gamete nuclei move from male to female and fuse. There isno fusion of gametangia. The male nuclei enter the female gamet-angium through a pore developed by the dissolution of gametangialwalls at the point of contact. In some fungi fertilization tube isformed for the passage. The antheridium disintegrates after thepassage of nucleus but the oogonium develops.Gametangial copulation occurs due to fusion of the contentsof the two contacting gametangia. In holocarpic forms where en-tire thallus acts as gametangium passage of one gametangial con-tent (male) to the other (female) through a pore developed at thecontact point. In others direct fusion of two gametongial cellsoccur.Spermatia, uninucleate, spore like male structure, producedby certain fungi are carried by insects, wind or water to the femalegametangia or to the receptive or somatic hypha. The contents of7675phycobiont (Gr mykes = fungus phykos=alga bios = life). Thelichen fungi are ascomycetes or basidiobycetes while the lichenalgae are blue green algae.The somatic structure of fungus consists of microscopicstrands of filaments branching in all directions and spreading overthe substratum. The filament known as hypha (pl.hyphaeGr=hypha=web) is a thin, tubular wall filled with a layer of proto-plasm. The protoplasm is continuous without any cross wall (sep-tum; L.septum= hedge, partition) in some fungi (asepatate myce-lium or coenocytic) and with cross walls (septate). The proto-plasm on each side of a septum is connected by living strandspassing through a central pore in the septum.The composition of the cell wall is not the same in all fungi.In some forms cellulose is the chief constituent and in higher fungichitin is the chief constituent. Callose a lignin like but carbohy-drate substances and other organic materials are also present.In the hypha a true nucleus with nuclear membrane a nucleo-lus and chromatin strands which organizes to chromosomes dur-ing division are seen. In aseptate hypha nucleus are embedded inthe cytoplasm uniformly throughout the mass and the condition iscalled coenocytic (Gr koinos= common + kytos = a hollow ves-sel). The individual cells of sepate hypha may contain 1,2 ormany cells. Uninucleate, binucleate, multinucleate cells (mostcommon) occur on fungi. Vacuoles, oil droplets and other inclu-sions are also present in the mycelium. The mycelium of somehigher fungi forms thick strands called rhizomorphs which are re-sistant to adverse conditions and remain dormant until conditionsare favourable. In parasitic fungi the mycelium may grow on sur-face or inside the host. It may be intercellular (growing betweencells) or intra cellular (penetrating into the cell). The food is ab-sorbed through the host cell wall in the former and in the latter adirect contact with protoplasm is established. Obligate plant patho-gens growing between cells produce haustoria (haustorium L

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Secondary homothallism occur in fungi during the spore for-mation of bipolar heterothallic fungi. The two nuclei of oppositemating type are present in each spore which upon germinationgives a thallus containing both A and a nuclei and then behaves ashomothallic.Some fungi derive the benefits of sexuality through para-sexuality without true sexual cycle (Gr.para=beside). In parasexualmethod plasmogamy, karyogamy and haploidization occur but notat specified points of life cycle. In the Deuteromycetes group para-sexuality occurs and no sexual reproduction. Some fungi repro-duce sexually and parasexually.In mycology certain organisms of uncertain affinity like thecellular slime molds and net slime molds are also studied. Thecellular slime molds are grouped under order Acrasiales. The cellsare naked haploid amoeba feeding on bacteria. The cells are notflagellated but cells aggregate together formingpseudoplasmodium. The cells never fuse but remain individuallybut cooperate. Sorocarps (Gr.soro=heap+karpos=fruit) are fruit-ing bodies. Cultivated soils are richer in cellular slime molds.The net slime molds are grouped in the orderL.abyrinthulales. These are aquatic, mostly marine or terrestrialorganisms with naked uninucleate spindle or oval shaped cells.These cells become interconnected by slime filaments forming anet along which they glide. The majority of species are marineassociated saprobicaly or parasitically with marine algae Ulva orcause a disease in higher plants Zostera marina.The lower fungi includes the true slime molds (Class: Myxo-mycetes), posteriosly uniflagellate fungi (Class: Chytridiomycetes)anteriorly uniflagellate fungi (Class: Hyphochytridiomycetes), in-cluding water molds, white rusts and downy mildews formingoospores (Class: Oomycetes)endoparasitic slime molds (Class:Plasmodiophoromycetes) and bread molds, fly fungi and animal7877spermatia pass into the receptive structure, female organ, througha pore developing at the contact point.In many of the higher fungi no s*x organs are produced andthe somatic cells functions like s*x organs as they come in contactand fuse.The nuclear cycle in fungi generally involve haploid, dip-loid cycle. The diploid nuclei resulting from karyogamy becomehaploid after meiosis. Heterokaryosis is a phenomenon whereinnuclei of the genetically similar or different fungi exist in the samecell of hypha. The cells may not contain the same number orsame kind of nuclei or the same proportion of each kind in a mix-ture of nuclei. Each nucleus is independent of all nuclei in theheterokarytic condition.The fungi may be classified on the basis of s*x as (1) her-maphroditic (2) dioecious and (3) sexually undiffentiated thallusproducing morphologically indistinguishable male or female. Onthe basis of sexual compatibility fungi are grouped as (1) Homothal-lic (2) heterothallic and (3) secondary homothallic fungi. Inhomothallism every thallus is self fertile and can reproducewithout another thallus. Hermophrodite thallus are of this type.No dioecious fungi can be homothallic. In heterothallic fungievery thallus is self sterile and requires another compatible thallusof different mating type. Heterothallic fungi may be either bipolarheterothallic or tetrapolar heterothallic. Two mating types differ-ing in their genetic make-up for the compatibility factor occur inthe biopolar mating type. Each of the nucleus of one mating typecarries the gene A and each of the nucleus of other mating typecarries gene a. Those thalli carrying opposite genes of the pair Aaare compatible. Four mating types occur in heterothallism whereinthe compatibility is determined by two pair of factors Aa and Bblocated in different chromosomes. Those thallai carrying nucleiof opposite genes of both the Mendelian pair Aa and Bb are com-patible forming the zygote of AaBb genotype.

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In certain cases the cells are enveloped with a thick walleven before they separate and are called chlamydospores(Gr.chlamys=mantle+spores=... spores). Fission is division ofa cell into two daughter cells by formation of a cross wall in someyeasts. Bud is a small outgrowth from a parent cell and when it isformed the nucleus divides and the daughter nucleus move intothe bud. The bud grows in size and breaks and forms a newindividual. Budding takes place in majority of yeasts and manyother fungi under certain conditions. Production of spores is thecommon method in many fungi. Spores vary in colour fromcolourless (hyaline Gr.hyaline= made of glass i.e., colourless)through green, yellow orange, red, brown to black and also varyin size and shape. Some fungi produce only one type of sporewhereas others produce more types. Asexual spores are calledsporangiospores when they are borne in sporangia a sac like struc-ture (Gr.sporos=seed,spore+angeion=vessel) or called conidiawhen borne on the tips of hypha (Gr konis=dust, idion, dimin suf-fix.) The whole content of sporangium may develop into one ormore spores. Sporangiospores are of two types zoospores andaplanospores. Zoospores are motile with one or two flagella whileaplanospores are non motile. The flagellum may be of whiplashor tinsel type.Sexual reproduction, the union of two compatible nuclei,consists of three phases viz., plasmogamy, karyogamy and meio-sis. Plasmogamy (Gr.plasma= a molded object i.e, a being + gamos=marriage, union) union of two protoplasts occur bringing tow hap-loid nuclei together in one cell. In karyogamy (Gr.karyon = nut,nucleus + gamos = marriage) fusion of the two nuclei occur intoone diploid zygote nuclei. This second phase follows immedi-ately plasmagamy on lower fungi and in higher fungi it is delayedresulting in a dikaryotic (dikaryon di=two + Gr.karyon=nut). thedikaryon = condition may be perpetuated from cell to cell by thedivision of the associated nuclei and by the separation of the twodaughter cells. Meiosis occur sooner or later after the fusion of8079traps (Class: Zygomycetes). The higher fungi are the sac fungi(Class: Ascomycetes) including yeasts, leaf curl, black molds,blue molds, perithecial fungi, cup fungi, morels, truffles, parasiticfungi of insects and arachnids, the imperfect fungi (Form Class:Deuteromycetes), smuts, rusts, jelly fungi, mushrooms, puffballsand stinkhorns (Class: Basidiomycetes).Fungi form new in-dividuals by sexual and asexual reproduction. Asexual (somaticor vegetative) reproduction does not involve union of nuclei orsex cells or s*x organs whereas sexual reproduction is by union oftwo nuclei. The fungus is known as holocarpic when the entirethallus is converted into one or more reproductive structures andboth somatic and reproductive phases do not occur together onthe same individual (Gr:holos= whole + karpos=fruit). In most ofthe fungi separate reproductive organs arise from a portion of thal-lus and the remainder remains as somatic structure continuing itsactivities. Such fungi are known as eucarpic(Gr.eu=good+karpos=fruit). The holocarpic forms are primitivethan eucarpic fungi. Stomata (pl.stromata Gr.stroma= mattress ) isa compact like a mattress on / in which fungal fructifications areformed. Scletotia (pl.sclerotia Gr.skelros= hard) is hard restingbody resisting unfavourable conditions that remains dormant untilfavourable conditions returns.Asexual reproduction results in the production of numerousindividuals and important in propagation of species, repeated sev-eral times whereas the sexual stage is produced once in a seasonor year. Asexual reproduction occurs in several ways like (i) fis-sion as in fission yeasts (ii) budding as in budding yeasts (iii) frag-mentation of somatic structure each of which giving rise to a newindividual (4) spore formation, each spore germinating to formnew individuals.In fragmentation the hypha breaks up into their componentcells called oidia (Oidium, Gr.oidion=small egg) or arthrospores(Gr.arthorn=joint+sporos=see... spore) which function like spores.

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The class Hyphochytridiomycetes consist of aquatic fungiproducing anteriorly unflagellate motile cells with tinsel flagel-lum. Rhicidiomyces apophysatus is parasite on the oogonia ofwater molds.The class Oomycetes consists of water molds, white rustsand downy mildews. These fungi produce asexually by means ofbiflagellate zoospores bearing one forward tinsel flagellum andone backward whiplash flagellum. Albugo, Peronospora,Plasmopra, Pythium and Phytophthora are parasitic on plants.The class Plasmodiophoromycetes consist of fungi whichare obligate endoparasites of vascular plants, algae and causinghypertrophy. Plasmodiophora brassicae cause club root of cab-bage. Spongospora subterranea causes powdery scab of potatoes.The class Zygomycetes are characterized by zygospore for-mation in sexual reproduction and non motile sporangiospores orconidia in asexual reproduction. The majority of them aresaprophytice living on dung, decaying plant or animal matter. Thecommon bread mold Rhizopus stolonifer is used for the industrialmanufacture of fumaric acid and cortisone. A few of them areweak parasites of fruits, soft rot of sweet potatoes.Entomopathogenic fungi like fly fungus Entomophthora muscaeare found in dead housefly. The zoopagaceus fungi parasitizeamoebae, rhizopods and nematodes.The class Trichomycetes consists of fungi associated withanthropods. They are widely distributed and not parasitic but com-mensals.The class Ascomycetes and the class Basidiomycetes areknown as higher fungi and produce ascospores and basidiosporesrespectively. The yeasts, black molds, green molds, the powderymildews, the cup fungi, the morels and the truffles are ascomycet-ous fungi. Many are parasitic on plants, some are saprophyticliving in soil, decaying logs and leaves. The yeast Saccharomyces8281two nuclei restoring the haploid condition in the four nuclei formed.In order to effect sexual reproduction some fungal species pro-duce male and female s*x organs (gametangia) in each thallus(hermophroditic species-bisexual (Gr.Hermes = the messenger ofthe Gods,the symbol of the male s*x + Aphrodite = the goddess oflove, the symbol of female s*x). In other species some thalli pro-duce only male s*x organs and others produce only female sexorgans (dioecious).Gametangia, the s*x organs, form cells called gametes ormay certain one or more nuclei. the morphologically similar butphysiologically different male and female gametangia and gametesare called isogametangia and isogametes. If they can be differen-tiated then they are called as heterogametangia and heteroga-metes. In heterogametangium the male is designated as anthe-ridium and the female is called as oogonium.The most common method of plasmogamy are (1)Planogametic copulation (2) gametangial contact (3) gametangialcopulation (4) spermatization (5) somatogamy.In Planogametic copulation two naked gametes, one or bothmotile fuse together. The gametes may be isogamous or anisoga-mous. In some cases the female is non motile and male is motile.The male gamete enters the oogonium and fertilizes the egg.The class Myxomycetes contain the true slime molds. Theacellular creeping somatic structure of slime molds are animal likein structure and physiology but the reproductive structures are plantlike producing spores. They live in moist shady places dead leaves,on decaying logs or other organic matter. They occur in grasseslawns and develop in bark of trees. They feed on bacteria, proto-zoa and other minute organisms.The class chytridiomycetes are coenocytic fungi producingmotile cells (zoospores) with a single posterior whiplash flagel-lum. They occur in aquatic habitat and some parasitize algae.

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cup fungi, earth tongues, the morels and the truffles that are rec-ognized by their cup or disc shaped fruiting bodies produced onthe ground. The brown rot of peach and other stone fruits is causedby Monilinia fructicola of this group. The truffles (genus Tuber)are commercially exploited as food in European countries. Theseries Laboullbeniomycetes include parasites of insects and arach-nids. Herpomyces parasitize cockroaches. The seriesLoculoascomycetidae are ascostromatic fungi that produce asci instromatic locules. These fungi are parasitic to plants and insects.Elsinoe faucetti causes citrus scab and E.ampelina cause anthra-cnose of grapes. Myriangium spp. are parasitic on insects.Mycospherella musicola causes sigatoka disease of banana.Venturia indqualis attacks apple.The form class Deuteromycetes includes those imperfectfungi that lack a sexual phase or perfect stage. Most of them aresaprophytic but many cause diseases of plants, animals and hu-man. It is presumed that the imperfect fungi represent conidialstages of ascomycetes whose perfect stage (ascigerous stage) arerarely formed or not been found or have been lost by these organ-isms in their evolution. Whenever sexual stages are found in afew species then they are classified under ascomycetes. In certaincases the perfect stage have been found to be similar to those ofBasidiomycetes. Hence fungi imperfercti are considered as conidialstages of ascomycetes or rarely as basidiomycetes whose sexualstages have not been found or do not exist. In this group para-sexual cycle brings the advantages of sexuality.Blastospores, conidiospores, chlamydospores, phialospores,anthrospores, porospores (conidia produced from the pores ofconidiosphores) are common in Deuteromycetes. The most im-portant species that cause plant diseases are Septoria thespsia (leafspot of Thespesia), Colletotrichum capsci (fruit rot of chillies)C.lindemuthianum ( bean anthracnose), Helminthosporium oryzae(sesame leaf spots of rice), Cercospora personata, C. arachidicola8483cerevisiae are used in bread leavening, production of beverageslike beer, wine, alcohol production, in single cell protein produc-tion and enzymes. Chaetomium is cellulolysic in soil aiding de-composition. The ergot fungus Claviceps purpurea cause plantdisease in rye, cumbu, etc., the sclerotia of which are deadly toanimals when consumed. The Penicillium that produces Pencillinantibiotic and the omnipresent Aspergilus spp., belong to this class.Ascus, the sac like structure containing definite number ofascopores are produced by the fungi in sexual reproduction. Eightare usually formed in an ascus but this may vary from 1 to 1000according to species. The asexual reproduction in ascomycetes isby fission, fragementation, blastospores (budding) anthrospores,chlamydospore or conidia. The fruiting bodies formed in asco-mycetes are (1) pycnidium (2) Acervulus and these contain conid-iophores bearing conidia. The ascomycetes have two differentreproductive phases, the ascus or sexual stage (ascigerous or per-fect stage) and the conidial or asexual stage (imperfect stage).Ascomycetes are classified based on the characteristics of perfectstage. But the conidial stages of number of ascomycetes have notbeen found. Further there are large number of fungi known onlyby conidial stages and are designated as imperfect fungi(form classDeuteromycetes). These are ascomycetes which have lost theirascus stage in the evolutionary development.The Ascomycetes are further divided into three sub-classes (1) Hemiascomycetetidae (2) Euascomycetidae and(3) Loculoascomycetidae. The Hemiascomycitidade includesyeasts (Order: Endomycetales) and leaf curl fungi (Order:Taphrinales). The Eusascomycetidae is divided into series(i) Plectomycetes (ii) Pyrenomycetes and (iii) Discomycetes and(iv) Laboul-bemycetes. The Plectomycetes include black molds(Asperigillus) green molds and blue molds (Penicillium). Theseries Pyrenomycetes contain those fungi that produce ascus inglobose or flask shaped perithecium. The Discomycetes include

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(tikka leaf spot of groundnut), Alternaria (leaf spot), Rhizoctoniasolani (root rot of groundnut), Sclerotium rolfsii (stem rot of rice)and Fusarium oxysporum f. cubense wilt of banana). Cercosporaapii was isolated form skin lessons of human.The class Basidiomycetes includes mushrooms, toad stools,puff balls, bracket fungi, the smuts, rusts and jelly fungi and stinkhorns. These produce their spores (basidiospores) usually on theoutside of the spore producing body called basidium and hencethe name Basidiomycetes. Basidiospores are uninucleate and hap-loid.The subclass Heterobasidiomycetidae includes jelly fungi,rusts and smuts. Jelly fungi are so called due to the jelly like fruit-ing bodies (some are waxy and cartilaginous). Some species ofTremella is used as food by Chinese people Septobasidiumparasitizesous scale insects. The wheat rust Puccinia graminis,Cumbu rust Puccinia penniseti, the bean rust Uromycesappendiculatus are devastating diseases. Uredia producing ure-dospores and Telia producing teleutospores are common in rusts.Puccinia graminis, the creal rust has an alternate host barberry inwhich aecial stage occurs but uredial and telial stages occur inwheat.The smuts are parasite and produce black dusty spore massresembling soot or s**t. Tilletia caries (bunt of wheat) Uromycismaydis (corn s**t) Ustilago scitamina (sugarcane s**t),Sphacelotheca sorghi (sorghum s**t) are very common diseases.The subclass Homobasidiomycetidae includes mushroom,shelf fungi, coral fungi, puff balls, earthstones, stink horns andbird’s nest fungi. Exobasidium attacks flowering plants causesabnormal swelleing of host tissues. Poria, Fomes, Polyporus andGanoderma are wood rotting fungi. Agaricus and Pleurotus areedible mushroom. Amanita is poisonous. A.muscaria , fly mush-room is used as an insecticide. The species of Glomus andAcaulospora are mycorrhizal fungui exploited as biofertilizer.8685Outline classification of Fungi by AlexopoulousThe fungi are classified with plants under the kingdompeantae and division mycota.Order:AcrasialesOrder:Labyrinthul... division:EumycotinaClass:Chytridiomycete...

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8887Subclass:HemiascomycetidaeOrder:En... class:EuascomycetidaeSeries:Plectomycete... ChaetomiaceaeClavicepitales ClavicepitaceaeSphar erialesSordariaceae,DiaporthalesPhylloch... class:DeuteromycetesForm order :Sphaeropsidales SphaeropsidaceaeZythiaceaeMelanconiales MelanconiaceaeMonilialesGyptococcaceaeMo... sterilia

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Class:BasidiomycetesSub class:HeterobasidiomycetesOrder:Tremella... UstilaginaceaeTilletiaceaeGraphiolaceaeF... class:HomobasidiomycetesOrder:Exobasidia... algae also known as sea weeds, pond scrubs, frog spittleand water mosses (L.alga = sea weeds Gr.phykos – sea weeds) arestudied under algology (Gr.phykology phykos-sea weeds+logos- dis-course or study. They are simple plants with autotiophic nutrition.They are chlorophyll bearing organisms (and their colourlessrelatives ) which are thalloid and have not differentiated as roots,stems and leaves.Their occurrence is universal and found in all kinds of habitatsin fresh as well as sea waters, soil, on within other plants and evenanimals, rock stones, in desert sand and snow fields. Based on theirhabitat they are classified as aquatic growing in fresh and brackishwater, terrestrial (edaphophytes), on rocks and stones (lithophytic),halophytic growing in water of high concentrations of salinity,psammon algae of sandy beaches, thermal algae of hot waters nearhot springs, cryophytic algae (on ice or snow) forming differentcolours of the snow. Epiphytic algae occurring within the cells ofother plants, Epizoic and endozoic occurring on shells of mollusces,nose of fishes and within Paramecium, Hydra and molluces. Thereare also algae parasitic on plants and animals. Planktonic algae, shellbearing algae and alga of lichens are also algae.

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The thallus in alga varies from (1) motle unicellular (Chlamy-domonas; Phacus), (2) motile colonial (Volvox; Eudorina), (3)Palmelloid (Chlamydomonas; Palmella dendroid (Prasinodadus),Coccoid (Chlorella), filamentous (Spirogyra; Nostoc),heterotrichous (Fritschiella), siphonaceous (Botrydium) uniaxial(Batrachospermum), multiaxial (Polysiphonia) and parenchymatous(Sargassam).The size is microscopic (0.5 mm in dia in Chlamydomonas toas large as 30 m or even more (Macrocystis). Each cell is found bya typical cell wall in all cases except in Euglena and Gymnodiniumwhere the cytoplasmic membrane called pellicle is present. The cellwall is bilayered composted mainly of cellulose and pandes with sub-stances like pectin, chitin, algin and fucoidon. In a few alga the wallis fortified with calcium, silica and magnesium carbonate.The motile member, zoospore and gametes of many algae bearflagella consisting of 2 central tubules surrounded by 9 peripheral tu-bules enclosed in a membrane. Flagella may be equal or unequal inlength, inserted apically or laterally and may be tinsel or whiplash.The cytoplasm contains contractile vacuoles, mitochondria,eyespot, chloroplast, nucleus, pyrenoids, chondriosormes and Golgibodies. In the prokaryotic blue green algae these are absent.The pigments in the alage vary with the group. They are chlo-rophyll a, chlorophyll b, β-carotene and xanthophylls. Phycobilins arepresent in Rhodophyceae and blue green algae.The food reserve is in the form of starch. But fats and oils arealso present in certain groups. Laminarin and mannitol are inphaeophyceae, Floridian starch, floridoside and mannoglycerate arethe chief reserve products in Rhodophyceae.9291The reproduction in alga is by (1) vegetative (2) asexual and(3) sexual process. The vegetative propagation is fragmentation, fis-sion, akinete formation, tuber, hormogonia and formation of adventi-tious thalli.Asexual reproduction takes place by release of protoplasts inthe form of zoospores, synzoospore, aplanospore, hypnospore,autospore, auxospore, carpospore, tetraspore, cyst, etc., These ger-minate into a new plant. Sexual reproduction takes place by theunion of cytoplasm and nuclear material of two gametes of two or-ganisms of the same species on three different ways viz., (1) Isogamy(fusion of morphologically similar gametes) (2) Anisogamy (fusion ofmorphologically dissimilar gametes) and (3) Oogamy (female is im-mobile and the male gamete is small and motile).The algae are important as food (Chlorella, Scenedesmus,Laminaria, Spirulina) as medicine (Chlorella ) as nitrogen fixingfertilizer (blue green algae) as fodder (Laminairia, Sargassum andFicus) and in the industrial preparations. Agar-agar is produced fromGelidium and Gracillaria. Iodine is from Laminaria andMacrocystis, carragenin (from Chondrus crispus), alginic acid fromLaminaria and filter aids (diabomaceous earth) from diatom are in-dustrially important products.The widely accepted Fritsch classification is outlined below.This algae were divided to (XI) classes (= phyceae) including theprocaryotric blue green algae which is grouped in classMyxophyceae.Outline Classification of AlageMyxophyceaeBlue green algaeChlorophyll aor CyanophyceaeProcaryoticB-carobeneEg. MosboeflavicinScytonemac-phycocyaminAnab...

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9493Self evaluation1. Give an account of biodiversity of microorganisms.2. Give an outline classification of bacteria.3. Write briefly on mycoplasma.4. Give an account of spore forming bacteria.5. Mention five important human pathogens and indicate theirtaxomic grouping.6. Describe briefly key characteristics of fungi considered for theirclassification.7. Give an account of somatic characteristics of fungi.8. Describe briefly the asexual propagation in fungi.9. Describe the sexual reproduction in fungi.10. Give an outline classification of fungi.11. Indicate the significance of smuts and rusts.12. Mention five important plant pathogens and indicate theirtaxomic grouping.13. Give an outline classification of algae.14. Give a brief description of sea weeds.15. Illustrates different types of spores in fungi.ChlorophyceaeGreen algaeChlorophyll aEg. Chlamydomonas Chlorophyll bVolvoxα and β caroteneChlorellaXanthophylsXanthophycea... green algaeChlorophyll a,ChloramoelaChlorophyll c,Heterochlorosβ-caroteneChlorothecaumXa... aSynedraChlorophyll cBaccillariaβ -caroteneSurinellafucoxanthinPhaeophycea... algaeChlorophyll aMacrocystisChlorophyll c,Ectocarpusβ-caroteneviolaxanthinefucox... algaeChlorophyll aChlorophyll bxanthophyllγ-phycocyarinγ-phycoerythrin... toremember1. Biodiversity of the organisms2. Different types of organisms their respectivetaxonomical positions