Qhov sib txawv tseem ceeb ntawm qhov tshwj xeeb thiab kev xaiv yog qhov tshwj xeeb yog qhov muaj peev xwm los ntsuas qhov tseeb ntawm cov khoom sib xyaw, qhov kev xaiv yog lub peev xwm los sib txawv cov khoom sib xyaw hauv ib qho sib tov.
Qhov tshwj xeeb thiab kev xaiv yog qhov tseem ceeb hauv kev tshuaj xyuas cov qauv uas muaj cov sib xyaw sib txawv. Cov ntsiab lus tshwj xeeb thiab kev xaiv tau tham tshwj xeeb hauv kev sib cuam tshuam enzyme-substrate. Peb tuaj yeem piav qhia txog qhov tshwj xeeb ntawm cov substrates thiab kev xaiv ntawm enzymes.
Qhov tshwj xeeb yog dab tsi?
Specificity yog lub peev xwm los ntsuas qhov tseeb ntawm cov khoom sib xyaw. Tsis tas li ntawd, qhov tshwj xeeb ntsuas qhov kev cuam tshuam los ntawm lwm yam khoom muaj nyob hauv ib qho qauv thaum lub sij hawm soj ntsuam ntawm ib qho kev ntsuas. Yog li ntawd, nyob rau hauv kev sib cuam tshuam enzyme-substrate, lo lus no piav qhia txog kev khi ntawm ib qho enzyme nrog "tshwj xeeb" substrate. Qhov ntawd txhais tau tias; nws yog lub peev xwm ntawm ib qho enzyme los catalyze ib qho kev tshuaj tiv thaiv biochemical yam tsis muaj kev koom tes hauv cov tshuaj tiv thaiv sab uas tshwm sim ntawm tib qhov chaw. Ntxiv mus, thaum txiav txim siab qhov tshwj xeeb, nws tsis yog qhov tseem ceeb los txheeb xyuas lwm cov substrate; Nws tsuas yog yuav tsum tau txheeb xyuas tsuas yog cov kev ntsuas xav tau hauv qhov sib tov.
Kev xaiv yog dab tsi?
Kev xaiv yog lub peev xwm los sib txawv ntawm cov khoom hauv kev sib xyaw ntawm ib leeg. Feem ntau, kev xaiv piav qhia tib lub tswv yim raws li qhov tshwj xeeb tab sis lawv cov ntsiab lus txawv me ntsis ntawm ib leeg hauv qhov ntawd, qhov tshwj xeeb piav qhia txog kev tshawb nrhiav qhov tseeb thaum xaiv xaiv piav qhia qhov sib txawv ntawm cov khoom sib xyaw. Hauv lwm lo lus, qhov tshwj xeeb tsis xav tau kev txheeb xyuas tag nrho cov khoom hauv qhov sib tov, tab sis kev xaiv xav tau qhov ntawd. Peb yuav tsum xav txog kev xaiv thaum peb yuav tshuaj xyuas ntau qhov sib txawv hauv kev sib xyaw es tsis yog ib qho tshuaj ntsuam xyuas.
Daim duab 01: Xaiv cov Cheebtsam uas dhau los ntawm Cell Membrane
Piv txwv li, thaum txiav txim siab qhov kev xaiv ntawm ib qho enzyme, peb tuaj yeem txiav txim siab tag nrho cov khoom sib xyaw hauv cov enzyme yuav khi nrog. Nws yog vim qee cov enzymes tuaj yeem ua rau hauv chav kawm ntawm cov tebchaw (uas muaj feem cuam tshuam rau ib leeg) tsis yog ib qho sib xyaw. Ntxiv mus, nyob rau hauv cov txheej txheem chromatographic, peb thaum kawg tau txais ib chromatogram nrog ob peb lub ncov uas piav txog ntau qhov kev xaiv xaiv hauv cov qauv uas peb txheeb xyuas.
Qhov txawv ntawm qhov tshwj xeeb thiab kev xaiv yog dab tsi?
Cov ntsiab lus tshwj xeeb thiab kev xaiv tau tham hauv qab enzyme-substrate kev sib cuam tshuam. Qhov sib txawv tseem ceeb ntawm qhov tshwj xeeb thiab kev xaiv yog qhov tshwj xeeb yog qhov muaj peev xwm los ntsuas qhov tseeb ntawm cov khoom sib xyaw thaum xaiv qhov sib txawv yog qhov muaj peev xwm los sib txawv ntawm cov khoom sib xyaw ntawm ib leeg. Tsis tas li ntawd, yog tias peb xav txog qhov kev xav tom qab cov ntsiab lus no, qhov tshwj xeeb piav qhia txog kev nrhiav qhov tseeb cov tshuaj ntsuam xyuas hauv kev sib tov thaum qhov kev xaiv piav qhia txog kev nrhiav ntau yam kev ntsuas hauv kev sib xyaw. Yog li, qhov no kuj yog qhov txawv ntawm qhov tshwj xeeb thiab kev xaiv.
Hauv kev txiav txim siab tshwj xeeb, peb yuav tsum txheeb xyuas tsuas yog tus kws tshuaj ntsuam xav tau; Txawm li cas los xij, hauv kev txiav txim siab xaiv, peb tuaj yeem txheeb xyuas ntau yam tseem ceeb hauv kev sib xyaw. Piv txwv li, substrate tshwj xeeb txiav txim siab qhov tshwj xeeb substrate uas yuav khi nrog ib qho enzyme thaum lub enzyme selectivity txiav txim siab cov substrates uas cov enzyme yuav khi nrog. Lwm cov piv txwv rau qhov tshwj xeeb suav nrog cov txheej txheem HPLC; Cov txheej txheem chromatographic yog cov piv txwv rau kev xaiv.
Summary – Specificity vs Selectivity
Cov ntsiab lus tshwj xeeb thiab kev xaiv tau tham hauv qab enzyme-substrate kev sib cuam tshuam. Qhov sib txawv tseem ceeb ntawm qhov tshwj xeeb thiab kev xaiv yog qhov tshwj xeeb yog lub peev xwm los ntsuas qhov tseeb ntawm cov khoom sib xyaw, qhov kev xaiv yog lub peev xwm los sib txawv cov khoom sib xyaw hauv ib qho sib tov.
