Mapuloteni denaturation

Conformation (loukitsa) wa unyolo peputayidi amatsogozedwa ndi wapadera wina mapuloteni. Zinthu mwapadera pali kusiyana lalikulu chiwerengero cha kumangidwa amene ziziyenda kapangidwe okhudza malo a molekyulu pawiri. Chifukwa, kusiyana kwathunthu molekyulu lonse (kapena mbali yokulirapo Hud) zimatengera mtundu wa koyilo mwachisawawa. Zimenezi amatchedwa "denaturation". Kusinthaku lingachititse kutentha kwa madigiri makumi asanu ndi makumi asanu ndi atatu. Motero, aliyense molekyulu, kusiyana chifukwa zingasiyane mu conformation ndi mzake.

Denaturation mapulotini chikuchitika mchikakamizo cha wothandizila aliyense angathe kuwononga nsinga sanali covalent. Zimenezi zingachitike atakumana zamchere kapena acidic, pamwamba pa chigawo gawo, pansi zochita za ena mankhwala organic (phenols, alcohols ndi ena). mapuloteni denaturation angayambe mchikakamizo cha guanidinium mankhwala enaake kapena urea. Anati wothandizila kupanga kumangidwa ofooka (hydrophobic, amaayoni, wa hydrogen) ndi magulu carbonyl kapena kwa amino wa peputayidi msana ndi anthu ena a zatsalira kwa amino asidi, m'malo omwe alipo mapuloteni awo maunyolo a hydrogen mkati tinthu lapansi. Chifukwa cha zimenezi, kusintha kumachitika mu dongosolo zasekondale ndi ukachenjede.

Kukana kuti denaturing wothandizila zimadalira kwenikweni pamaso pa molekyulu mankhwala mapuloteni kumangidwa disulfide. Trypsin woletsa ali nsinga atatu S - S. Mu chikhalidwe cha kuchira mapuloteni denaturation sikuchita zinthu zina. Ngati kenako kuyika kulumikizana mu zinthu pamene makutidwe ndi okosijeni ikuchitika SH-magulu a cysteine ndi mapangidwe kumangidwa disulfide, ndi conformation choyambirira wabwezeretsedwa. Pamaso pa ngakhale limodzi disulfide chomangira kwambiri kumawonjezera mtendere wa kapangidwe okhudza malo.

mapuloteni denaturation, amangoona limodzi ndi kuchepa solubility. Pamodzi ndi izi precipitate zambiri mitundu. Kumachitika mu mawonekedwe a "mapuloteni curdled." Pa woipa mkulu wa mankhwala mu njira, "coagulation" amaloŵamo yankho lonse, monga Mwachitsanzo, izi zimachitika pamene otentha mazira. Pamene denaturation zomanga thupi limataya ntchito zake kwachilengedwenso. Mfundo imeneyi zachokera ntchito karboliki asidi (phenol amadzimadzi yothetsera) monga chinthu antiseptic.

Kusakhazikika kwa kapangidwe okhudza malo, Mwina mkulu kulephera mchikakamizo cha wothandizila zosiyanasiyana ndi kwambiri kovuta kupeza ndi kafukufuku mapuloteni. Komanso analenga mavuto ena pamene ntchito mankhwala mankhwala ndi malonda.

Ngati denaturation mapuloteni zinachitikadi malinga ndi kutentha, wosakwiya kuzirala kumachitika zinthu zina ndondomeko renativatsii - ayambe nzika (pachiyambi) conformation. Zimenezi zikutsimikizira kuti kuika unyolo peputayidi mogwirizana ndi dongosolo chachikulu.

Mapangidwe mbadwa conformation (gwero malo) ndi ndondomeko lachibadwa. M'mawu ena, dongosolo limeneli limafanana ndi osachepera kuchuluka kwa ufulu mphamvu zopezeka molekyulu ndi. Munthu angathe chifukwa Ndizachidziwikire kuti kapangidwe okhudza malo pawiri ndi ndiyotengera mu akuyambira kwa amino asidi unyolo peputayidi. Kuchita zimenezi zikutanthauza kuti polypeptides zonse zokhudzana ndi kusinthana kwa kwa amino zidulo (mwachitsanzo, mioglobinovye peputayidi unyolo), adzachotsa ndi conformation zofanana.

Mapuloteni akhoza kukhala kusiyana kwambiri kapangidwe chachikulu, ngakhale pang'ono kapena zofanana mwamtheradi mu conformation.