Qhov sib txawv tseem ceeb ntawm cov tshuaj tiv thaiv kab mob thiab theem kev hloov pauv yog qhov kev hloov pauv ntawm cov tshuaj tiv thaiv kab mob yog cov txheej txheem uas hais txog kev qhia ntawm antigenically txawv cov proteins, carbohydrate lossis lipids ntawm lawv qhov chaw thaum lub sij hawm hloov pauv yog qhov kev hloov pauv ntau zaus ntawm thiab tawm ntawm kev hloov ntawm phenotype. kev qhia.
Antigenic thiab theem variation yog ob hom molecular mechanisms siv los ntawm cov kab mob kom tsis txhob muaj lub cev tiv thaiv kab mob. Lawv muaj feem cuam tshuam rau ib leeg. Cov txheej txheem no tso cai rau microbes, tshwj xeeb tshaj yog cov kab mob, hloov mus rau ntau tshaj ib puag ncig. Raws li qhov tshwm sim ntawm theem thiab kev hloov pauv antigenic, ib qho heterogenic phenotype ntawm cov kab mob clonal yog tsim. Hauv cov pej xeem no, cov tib neeg lub hlwb qhia cov theem sib txawv ntawm cov proteins lossis ib qho ntawm ntau hom antigenic ntawm cov protein. Cov kev hloov pauv no feem ntau yog cov tswv yim ua phem ua phem los ntawm cov kab mob.
Dab tsi yog Antigenic Variation?
Antigenic variation yog ib lub tshuab molecular uas hais txog qhov kev qhia ntawm kev ua haujlwm tau txais kev txuag thiab antigenically txawv moieties nyob rau hauv cov pej xeem clonal. Siv cov txheej txheem no, cov kab mob hloov pauv lawv cov protein, carbohydrates lossis lipids, uas yog antigens nyob rau ntawm lawv qhov chaw. Yog li, vim muaj qhov sib txawv ntawm cov tshuaj antigenic, cov kab mob tuaj yeem hloov pauv lossis hloov cov molecular muaj pes tsawg leeg ntawm lawv cov antigens saum npoo. Los ntawm kev hloov cov qauv no, lawv zam kev tiv thaiv lub cev tiv thaiv kab mob. Muaj ntau yam txheej txheem saum npoo ntawm tsiaj cov kab mob vim muaj qhov sib txawv ntawm cov tshuaj antigenic thiab cov theem hloov pauv. Cov kab mob ib ntus camouflage lawv tus kheej thiab tiv thaiv kev tshem tawm tag nrho cov pej xeem los ntawm tus tswv tsev tiv thaiv kab mob. Cov piv txwv zoo tshaj plaws rau cov kab mob uas qhia tias muaj kev sib txawv ntawm cov kab mob yog cov genera Neisseria thiab Streptococci. Neisseria hom sib txawv lawv cov pili raws li qhov tshwm sim ntawm kev hloov pauv antigenic. Nws pab cov tsiaj no nyob rau hauv adhesion. Hauv qhov sib piv, Streptococci hloov lawv cov M protein.
Daim duab 01: Antigenic Variation
Kab mob tuaj yeem hloov kho lawv cov genomes nrawm heev thiab ua kom lub cev tiv thaiv kab mob tsis paub txog lawv. Qhov no yog vim qhov txawv ntawm cov tshuaj tiv thaiv kab mob uas pom hauv cov kab mob. Muaj rau ntau hom kev sib txawv ntawm cov tshuaj tiv thaiv kab mob xws li antigenic drift, hloov, sib cais, nqa, sift, thiab khoom plig.
Phase Variation yog dab tsi?
Phase variation yog lub tshuab molecular uas tso cai rau cov kab mob thiab lwm yam microbes kom tsis txhob muaj lub cev tiv thaiv kab mob. Ntxiv mus, nws tso cai rau cov kab mob cuam tshuam nrog ntau qhov chaw. Phenotypic variation tuaj yeem txhais tau tias yog kev hloov pauv ntawm cov protein qhia los ntawm ON mus rau theem OFF. Nyob rau hauv lwm yam lus, theem variation yog hais txog lub siab zaus ntawm thiab tawm switching ntawm phenotype qhia. Raws li qhov tshwm sim ntawm kev hloov pauv theem, theem ntawm kev qhia ntawm cov protein sib txawv ntawm cov tib neeg lub hlwb ntawm cov pejxeem. Cov kev hloov pauv no feem ntau tshwm sim random ntawm cov zaus. Txawm li cas los xij, lawv tuaj yeem hloov kho los ntawm ib puag ncig ib puag ncig. Thaum kawg, qhov kev hloov pauv theem ua rau muaj cov pej xeem phenotypically heterogeneous.
Daim duab 02: Theem Variation
Phase variation tshwm sim nyob rau hauv ntau yam kab mob, nrog rau cov kab mob thiab nonbacterial cov ntaub ntawv xws li protozoans thiab kab mob, thiab lwm yam. Ib qho piv txwv ntawm theem variation nyob rau hauv gram-negative kab mob yog cov kev hloov nyob rau hauv observable phenotypes pom nyob rau hauv cov qauv nto xws li fimbria, flagella, txheej membrane proteins thiab lipopolysaccharides.
Dab tsi yog qhov zoo sib xws ntawm Antigenic thiab Phase Variation?
- Phase thiab antigenic variation ua rau muaj heterogenic phenotype ntawm cov kab mob clonal.
- Antigenic thiab theem variation ua rau cov kab mob virulence thiab pab cov kab mob evade lub party tiv thaiv kab mob
- Vim cov txheej txheem no, cov kab mob muaj ntau yam ntawm cov qauv saum npoo.
Qhov txawv ntawm Antigenic thiab Phase Variation yog dab tsi?
Antigenic variation yog hais txog qhov kev qhia ntawm kev ua haujlwm tau txais txiaj ntsig thiab antigenically txawv moieties hauv cov pej xeem clonal. Ntawm qhov tod tes, kev hloov pauv theem yog hloov pauv ntawm cov protein qhia los ntawm ON mus rau theem OFF. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm antigenic thiab theem variation. Tsis tas li ntawd, raws li qhov tshwm sim ntawm kev hloov pauv ntawm cov tshuaj tiv thaiv, cov kab mob hloov pauv lawv cov proteins, carbohydrates lossis lipids, uas yog antigens nyob rau ntawm lawv qhov chaw. Hauv qhov sib piv, raws li qhov tshwm sim ntawm kev hloov pauv theem, cov kab mob sib txawv ntawm qib kev qhia ntawm cov protein ntawm cov tib neeg lub hlwb ntawm cov pejxeem.
Summary – Antigenic vs Phase Variation
Antigenic thiab theem variation yog ob lub tshuab molecular uas pab cov kab mob sib kis kom tsis txhob muaj lub cev tiv thaiv kab mob. Antigenic variation tshwm sim nyob rau hauv kev hloov ntawm nto antigens (proteins, carbohydrates thiab lipids) thiaj li yuav ntxias tus tswv cov tshuaj tiv thaiv tsis paub lawv. Ntawm qhov tod tes, kev hloov pauv theem sib txawv ntawm theem ntawm kev qhia ntawm cov protein ntawm cov hlwb ntawm cov pejxeem. Nws yog ua los ntawm lub siab zaus ntawm thiab tawm kev hloov ntawm phenotype qhia. Yog li, qhov no qhia txog qhov sib txawv ntawm antigenic thiab theem variation.
