Cov kab mob nitrifying. Qhov tseem ceeb ntawm cov kab mob nitrifying

Raws li hom khoom noj, tag nrho cov tsiaj txhu paub muaj sia nyob faib ua ob hom tsiaj loj: hetero- thiab autotrophs. Ib tug txawv feature ntawm lub yav tas yog lawv muaj peev xwm rau nws tus kheej-kev tsim kho ntawm tshiab ntsiab ntawm cov pa roj carbon dioxide thiab lwm yam inorganic tshuaj.

Cov chaw ntawm lub zog txhawb lawv txoj haujlwm tseem ceeb, ua rau lawv txoj kev faib rau cov duab yees duab (fluorescofs) thiab cov chemoautotrophs (qhov chaw-mineral). Thiab, nyob ntawm seb lub npe ntawm cov substrate, uas oxidizes chemoauthortopaths, lawv muab faib ua hydrogen thiab nitrifying cov kab mob, zoo li mus rau leej faj thiab cov kab mob hlau.

Tsab xov xwm no yuav muab rau ntau tshaj plaws - pawg nitrosating.

Keeb kwm ntawm kev nrhiav pom

Nyob rau hauv nruab nrab ntawm lub xyoo pua puv 19, German zaum ua pov thawj tias cov txheej txheem ntawm nitrification yog lom. Tawm, lawv pom tias qhov sib ntxiv ntawm chloroform rau cov dej ntxuav tau cov oxidation ntawm ammonia. Tab sis lawv piav tsis tau vim li cas qhov no tshwm sim.

Qhov no tau tiav ntau xyoo tom qab los ntawm tus kws tshawb fawb Lavxias teb sab Vinogradsky. Nws hu ua ob pawg kab mob, uas maj mam muab koom nrog hauv kev ua dej num. Yog li, ib pab pawg neeg oxidizing ammonia los muab acid nitrous, thiab tsuas yog lub thib ob pab pawg neeg ntawm cov kab mob lub luag hauj lwm rau nws cov transformation mus rau hauv nitric. Tag nrho cov kab mob nitrifying uas cuam tshuam rau hauv txoj kev no yog gram-negative.

Ntaus ntawm oxidation txheej txheem

Cov txheej txheem ntawm nitrite tsim los ntawm ammonium oxidation muaj ntau theem, thaum lub sij hawm uas nitrogen-muaj sib txuas nrog ntau theem ntawm oxidation ntawm NH pawg raug tsim.

Thawj cov khoom ntawm ammonium oxidation yog hydroxylamine. Feem ntau cov yuav nws yog generated vim lub xam nrog ntawm molecular oxygen nyob rau hauv cov pab pawg neeg NH _4, txawm hais tias tus txheej txheem no tsis yog definitively pov thawj thiab tseem debated.

Ntxiv hydroxylamine hloov dua siab tshiab rau nitrite. Txawm li cas los xij, tus txheej txheem yog ua los ntawm kev tsim ntawm NOH (giponitrite) nrog kev dim ntawm nitrous oxide. Nyob rau hauv cov ntaub ntawv no, zaum ntseeg zus ntawm cov pa roj nitrous oxide cia li ib tug byproduct ntawm lub synthesis, vim hais tias ntawm lub rov qab los ntawm nitrite.

Ntxiv nrog rau kev siv tshuaj ntawm cov tshuaj, thaum lub sijhawm ntawm qhov kev lag luam tawm ntawm ib qho loj ntawm lub zog tso tawm. Zoo li ua li cas hauv heterotrophic aerobic organisms, qhov no qhov synthesis ntawm ATP molecules yog txuam nrog oxidation-txo cov txheej txheem, vim tias cov electrons tau pauv mus rau oxygen.

Thaum lub oxidation ntawm nitrite, lub luag haujlwm tseem ceeb yog ua los ntawm cov txheej txheem ntawm qhov rov qab electron thauj. Xam ntawm nws cov electrons hauv cov saw tshwm sim ncaj qha rau hauv cytochromes (C-hom thiab / lossis A-hom), thiab qhov no yuav tsum tau siv nyiaj ncaj ntau zog. Yog li ntawd, chemoautotrophic nitrifying bacteria tau muab tag nrho nrog lub zog cia tsim nyog, uas yog siv rau cov txheej txheem ntawm lub tsev thiab kev txhim kho carbon dioxide.

Cov hom kab mob nitrifying

Hauv thawj theem ntawm nitrification, plaub hom nitrobacteria koom nrog:

• Nitrosomonas;
• Nitrocystis;
• Nitrosolus;
• Nitrospira.

Los ntawm txoj kev, ntawm daim duab koj tau pom tau pom nitrifying bacteria (duab nyob rau hauv lub tshuab kuaj kab mob).

Txoj kev sim ntawm lawv yog qhov nyuaj heev, thiab feem ntau nws yog tsis yooj yim sua kom ib leeg tawm ntawm cov qoob loo, yog li ntawd lawv txoj kev xav yog feem ntau nyuaj. Tag nrho cov kab mob no muaj qhov siab txog li 2-2.5 microns thiab feem ntau yog oval lossis sib npaug (nrog rau kev zam ntawm nitrospires, uas muaj qhov pom ntawm lub pas). Lawv muaj peev xwm ntawm kev faib binary thiab kev tswj kev coj vim yog flagella.

Qhov thib ob theem ntawm nitrification yuav:

• Genus Nitrobacter;
• Genus ntawm nitrosoin;
• Nitrococus.

Qhov feem ntau kawm txog cov kab mob ntawm genus Nitrubacter, npe tom qab nws discoverer, Vinogradsky. Cov kab mob nitrifying no muaj ib qho pear-like-form of cells, multiply by budding, nrog rau kev tsim ntawm lub xov tooj ntawm tes (vim yog tus flagellum) tus ntxhais ntawm tes.

Cov qauv ntawm cov kab mob

Cov kab mob nitrate tshawb tau muaj cov qauv zoo sib xws ntawm cov kab mob Gram-negative microorganisms. Qee leej ntawm lawv muaj ib qho tsim kom muaj lub cev sib txuas hauv lub nruab nrab ntawm lub xov tooj ntawm tes, thaum nyob rau hauv lwm tus lawv nyob ntau dua nyob rau ntawm qhov chaw los yog ua ib qho qauv hauv daim ntawv ntawm ib lub tais uas muaj ob peb nplooj ntawv. Thaj li, nws yog nrog cov formations uas cov enzymes yog txuam nrog kev koom tes hauv cov txheej txheem oxidation ntawm cov substrates ntawm nitrifiers.

Hom ntawm cov zaub mov nitrifying kab mob

Nitrobakterii yog obligate autotrophs vim hais tias tsis muaj peev xwm siv exogenous organic tshuaj. Txawm li cas los xij, lub peev xwm ntawm qee hom ntawm cov kab mob nitrifying los siv qee cov organic sib xyaw ua ke tau tsim muaj kev sim siab.

Nws tau pom tias tus substrate uas muaj poov xab autolysates, serine thiab glutamate nyob rau hauv qis concentrations, stimulated qhov kev loj hlob ntawm nitrobacteria. Qhov no tshwm sim ob leeg nyob rau hauv lub xub ntiag ntawm nitrite, thiab nyob rau hauv lub qhaj ntawv los ntawm nyob rau hauv lub nruab nrab, txawm hais tias tus txheej txheem yog npaum li cas qeeb qeeb. Conversely, thaum muaj nitrite, qhov oxidation ntawm acetate yog suppressed, tab sis tus incorporation ntawm cov pa roj carbon dioxide, ntau cov amino acids thiab lwm yam cellular yam loj.

Raws li cov kev sim ntau, cov ntaub ntawv tau txais tau tias cov kab mob nitrifying tseem muaj cuab kav hloov mus rau kev noj haus heterotrophic, tab sis yuav ua li cas tsim thiab ntev npaum li cas lawv tuaj yeem nyob rau hauv tej yam kev mob tseem yuav pom. Thaum cov ntaub ntawv txaus sau qhov tsis txaus siab los txiav txim siab zaum kawg ntawm qhov teeb meem no.

Habitat thiab qhov tseem ceeb ntawm cov kab mob nitrifying

Nitrifying cov kab mob yog cov chemoautotrophs thiab yog dav faib rau hauv cov xwm. Lawv pom nyob txhua qhov chaw: nyob rau hauv av, ntau yam substrates, thiab kuj reservoirs. Ua lawv lub neej zoo heev txhawb rau tag nrho cov nitrogen voj voog nyob rau hauv cov xwm , thiab nyob rau hauv qhov tseeb tej zaum yuav mus txog enormous proportions.

Piv txwv li, ib kab mob xws li nitrocystis oceans, cais los ntawm hiav txwv Atlantic, yog hais txog kev txiav txim siab halophiles. Nws tuaj yeem tshwm sim nyob rau hauv seawater lossis substrates uas muaj nws. Rau cov kab mob zoo li no, tsis yog qhov chaw tseem ceeb xwb, tab sis kuj tseem muaj xws li pH thiab qhov kub.

Txhua tus kab mob nitrifying paub yog dej num raws li txoj cai aerobes. Yuav kom oxidize ammonium rau nitrous acid, thiab nitrous acid rau nitric acid, lawv yuav tsum tau oxygen.

Tej yam kev mob

Lwm qhov tseem ceeb, uas cov kws tshawb fawb tau tshwm sim, yog qhov chaw uas cov kab mob nitrifying nyob hauv tsis muaj cov organic. Ib qho kev tshawb xav tau hais tias cov kab mob no tsis tuaj yeem siv tau cov organic compounds los ntawm sab nraud. Lawv txawm tau hu ua obligate autotrophs.

Tom qab, qhov teebmeem ntawm cov kabmob ntses, kua qab, peptone, glycerol thiab lwm yam kabmob ntawm cov kabmob nitrifying tau muaj pov thawj, tabsis kev sim tsis txhob tso tseg.

Qhov tseem ceeb ntawm cov kab mob nitrifying rau av

Txog rau tsis ntev los no, nws ntseeg tias nitrifiers txaus ntshai rau cov av, nce nws cov fertility los ntawm splitting ammonium rau nitrates. Cov yav tas tsis yog tsuas yog zoo absorbed los ntawm cov nroj tsuag, tab sis kuj nyob rau hauv lawv tus kheej nce lub solubility ntawm ib co minerals.

Txawm li cas los, nyob rau xyoo dhau los scientific views tau hloov lawm. Qhov tsis zoo ntawm microorganisms piav txog fertility ntawm cov av tau qhia. Cov kab mob nitrate, tsim nitrates, acidify ib puag ncig, uas tsis yog ib lub sijhawm zoo, thiab tseem ua rau ntau dua qhov ua rau cov av nrog ammonium ions tsawg dua nitrates. Ntxiv mus, nitrates yog txo kom lub peev xwm N ₂ (nyob rau hauv denitrifakatsii), uas nyob rau hauv lem ua rau yus lub havzoov ntawm cov av nrog nitrogen.

Qhov txaus ntshai ntawm cov kab mob nitrifying yog dab tsi?

Qee hom ntawm nitrobacteria nyob rau hauv muaj ib qho organic substrate tau oxidize ammonium, ua kom hydroxylamine, thiab tom qab nitrites thiab nitrates. Tsis tas li ntawd, vim yog cov tshuaj tsis haum, tej zaum hydroxamic acids yuav tshwm sim. Tshaj li, ntau cov kab mob ua rau cov txheej txheem ntawm nitrification ntawm ntau lub tebchaw uas muaj nitrogen (oximes, amines, amides, hydroxamates thiab lwm cov ntsiab lus nitro).

Qhov ntsuas ntawm heterotrophic nitrification hauv qee yam kev mob yuav tsis yog loj tshaj plaws, tab sis kuj raug dejnum heev. Qhov txaus ntshai yog hais tias thaum lub sij hawm xws hloov hloov tsim ntawm tshuaj lom neeg, mutagens thiab carcinogens tshwm sim. Yog li ntawd, cov kws tshawb fawb tau ua hauj lwm zoo rau txoj kev kawm ntawm lub ntsiab lus no.

Kev lim ntshav, uas yog ib txwm nyob ntawm tes

Nitrifying cov kab mob tsis yog ib qho kev paub daws teeb meem, tab sis ib daim ntawv ntawm lub neej zoo heev. Ntxiv mus, feem ntau lawv siv los ntawm tib neeg.

Piv txwv, nyob rau hauv cov dej lim tshuaj rau cov thoob dej yug ntses yog cov kab mob no. Hom tshuaj ntxuav vaj tse no tsis tshua kim dua thiab tsis yog siv zog ua kom tau tu, tab sis tib lub sijhawm nws yuav tsum tau muaj qee qhov kev xav tau kom ua tau zoo kom muaj kev loj hlob thiab tseem ceeb ntawm cov kab dej nitrifying.

Qhov zoo tshaj plaws microclimate rau lawv yog qhov kub ambient (nyob rau hauv rooj plaub no dej) ntawm qhov kev txiav txim ntawm 25-26 degrees Celsius, ib qhov chaw ntawm cov pa oxygen thiab muaj cov nroj tsuag dej.

Nitrifying cov kab mob hauv kev ua liaj ua teb

Yuav kom nce cov qoob loo, cov tswv teb siv ntau hom chiv muaj nitrifying bacteria.

Cov zaub mov av hauv qhov teeb meem no yog muab los ntawm nitrobacteria thiab nitrogen. Cov kab mob no yuav tsum muab cov khoom tsim los ntawm cov av thiab dej, uas tsim kom muaj qhov loj txaus ntawm lub zog thaum lub sijhawm oxidation. Qhov no yog qhov kev sib txuas lus ntawm chemosynthesis, thaum lub zog tau txais mus rau tsim ntawm lub cev molecules ntawm cov organic keeb kwm ntawm carbon dioxide thiab dej.

Rau cov kab mob no, tsis tas muab cov khoom noj ntawm lawv qhov chaw - lawv tuaj yeem tsim lawv tus kheej. Yog li, yog tias cov nroj tsuag ntsuab, uas yog cov autotrophs, xav tau lub hnub ci, ces rau cov kab mob nitrifying nws tsis tsim nyog.

Kev tu tus kheej ntawm cov av

Av yog ib qho zoo kawg nkaus substrate rau kev loj hlob thiab kev yug ntawm tsis tsuas yog nroj tsuag, tab sis kuj muaj sia nyob ntau yam. Yog li ntawd, nws lub xeev thiab kev sib npaug li cas tseem ceeb heev.

Nws yuav tsum nco ntsoov tias kev tu tsiaj txhu ntawm cov av yog muab, nrog rau lwm yam, los ntawm cov kab mob nitrifying. Lawv, thaum nyob hauv av, dej lub cev los yog humus, hloov ammonia, uas secrete lwm microorganisms thiab pov tseg cov ntaub ntawv organic, rau hauv nitrates (yuav tsum tau ntau dua, hauv ntsev ntawm nitric acid). Tag nrho cov txheej txheem muaj ob theem:

1. Oxidation ntawm ammonia rau nitrite.
2. Oxidation ntawm nitrite rau nitrate.

Hauv qhov no, txhua theem yog muab los ntawm cais hom kab mob.

Lub sib tham vicious circle

Lub voj voog ntawm lub zog thiab kev tswj ntawm lub neej hauv lub ntiaj teb yog ua tau vim yog kev ua tiav ntawm tej yam hauv kev ua neej nyob hauv lub neej ntawm txhua yam nyob. Thaum xub thawj siab ib muag tsis yooj yim to taub yog dab tsi nyob rau hauv qhov teeb meem, tab sis nyob rau hauv qhov tseeb txhua yam yog yooj yim heev.

Cia li xav txog cov duab hauv qab no los ntawm lub tsev kawm ntawv phau ntawv qhia:

1. Inorganic tshuaj yog ua los ntawm cov kab mob thiab ua li cas tsim tej yam kev mob nyob rau hauv cov av rau cov nroj tsuag kev loj hlob thiab kev noj haus.
2. Lawv, dhau los, yog qhov tseem ceeb ntawm lub zog rau feem ntau cov herbivores.
3. Tom qab cov saw ntawm qhov txuas qhov tseem ceeb no yog cov tsiaj txhu, nws lub zog yog, raws li, lawv cov tub tiv txawb herbivorous.
4. Cov neeg paub tias yuav tsum muaj cov tsiaj txhu dua, uas txhais tau hais tias peb tuaj yeem tau txais lub zog los ntawm ob lub ntiaj teb thiab cov tsiaj.
5. Thiab twb yog peb tus kheej seem ntawm kev ua si tseem ceeb, as Well as cov nroj tsuag thiab tsiaj txhu, ua hauj lwm raws li ib qho tshuaj substrate rau microorganisms.

Yog li, nws puv lub voj voog, ua haujlwm tsis tu ncua thiab txav lub neej ntawm tag nrho lub neej hauv ntiaj teb. Kev paub txog cov qauv no, nws tsis yooj yim los xav txog tias kev sib tw ntau npaum li cas thiab qhov tseeb tiag yog lub hwj chim ntawm txhua yam thiab txhua yam nyob.

Xaus

Nyob rau hauv tsab xov xwm no, peb tau sim teb cov nqe lus nug ntawm cov kab mob nitrifying dab tsi hauv biology. Raws li koj tau pom, txawm tias cov ntaub ntawv tseem ceeb ntawm cov kev ua si tseem ceeb, ua haujlwm thiab cuam tshuam ntawm cov kab mob no, tseem muaj teeb meem ntau ntawm cov teeb meem ntxiv uas yuav tsum tau tshawb nrhiav dua ntxiv.

Nitrifying cov kab mob hu ua chemotrophs. Lub hauv paus ntawm lub zog rau lawv muaj ntau hom minerals. Txawm tias lawv loj npaum li cas los, cov kab mob nyob hauv ntiaj teb ua rau lub ntiaj teb nyob ib puag ncig lawv.

Raws li paub, chemotrophs tsis tuaj yeem nqus cov organic sib txuas uas nyob hauv cov substrate (av los yog dej). Lawv, ntawm qhov tsis sib xws, tsim cov khoom siv rau kev tsim ntawm lub neej thiab kev ua haujlwm ntawm tes.