Kev tsim qauv thiab kev daws teeb meem ntawm polypeptide peptide saw

I. Cov ntsiab lus
Peptides yog cov macromolecules tshwj xeeb xws li lawv cov kab ke txawv txawv hauv lawv cov tshuaj thiab lub cev.Qee cov peptides nyuaj rau kev sib txuas, thaum lwm tus kuj yooj yim rau kev sib txuas tab sis nyuaj rau purify.Qhov teeb meem siv tau yog tias feem ntau peptides yog me ntsis soluble nyob rau hauv aqueous daws, yog li nyob rau hauv peb purification, tus coj ib feem ntawm cov hydrophobic peptide yuav tsum tau yaj nyob rau hauv non-aqueous kuab tshuaj, Yog li ntawd, cov kuab tshuaj los yog buffers no tej zaum yuav hnyav heev inconsistent nrog rau kev siv. ntawm cov txheej txheem kev sim tshuaj lom neeg, kom cov kws tshaj lij raug txwv tsis pub siv cov peptide rau lawv tus kheej lub hom phiaj, kom cov hauv qab no yog ob peb yam ntawm kev tsim peptides rau cov kws tshawb fawb.

Kev tsim qauv thiab kev daws teeb meem ntawm polypeptide peptide saw
Qhov thib ob, qhov tseeb xaiv ntawm hluavtaws peptides nyuaj
1. Tag nrho qhov ntev ntawm cov kev tswj hwm qis
Peptides tsawg dua 15 qhov seem yog yooj yim dua vim tias qhov loj ntawm peptide nce thiab purity ntawm cov khoom crude txo.Raws li tag nrho ntev ntawm cov saw peptide nce siab tshaj 20 seem, cov khoom lag luam meej yog qhov kev txhawj xeeb tseem ceeb.Hauv ntau qhov kev sim, nws yog qhov yooj yim kom tau txais cov txiaj ntsig tsis xav tau los ntawm kev txo qis tus lej seem hauv qab 20.
2. Txo tus naj npawb ntawm hydrophobic residues
Peptides nrog qhov loj tshaj ntawm hydrophobic residues, tshwj xeeb tshaj yog nyob rau hauv cheeb tsam 7-12 residues los ntawm C-terminus, feem ntau ua rau muaj teeb meem hluavtaws.Qhov no pom tau tias yog kev sib xyaw ua ke tsis txaus vim tias daim ntawv B-fold tau txais hauv kev sib txuas."Hauv qhov xwm txheej zoo li no, nws yuav muaj txiaj ntsig zoo los hloov ntau dua ob qhov zoo thiab tsis zoo, lossis muab Gly lossis Pro rau hauv peptide txhawm rau qhib peptide muaj pes tsawg leeg."
3. Kev txo qis ntawm "nyuaj" seem
"Muaj ntau tus Cys, Met, Arg, thiab Sim residues uas feem ntau tsis tau nkag mus ua ke."Ser feem ntau yuav raug siv los ua lwm yam tsis muaj oxidative rau Cys.
Kev tsim qauv thiab kev daws teeb meem ntawm polypeptide peptide saw

Thib peb, txhim kho kev xaiv kom raug ntawm soluble hauv dej
1. Kho lub sijhawm N lossis C
Cov txheeb ze rau acidic peptides (uas yog, tsis zoo them ntawm pH 7), acetylation (N-terminus acetylation, C terminus ib txwm tuav ib pawg carboxyl dawb) tshwj xeeb yog pom zoo kom nce tus nqi tsis zoo.Txawm li cas los xij, rau cov peptides yooj yim (uas yog, raug them zoo ntawm pH 7), amination (dawb amino pawg ntawm N-terminus thiab amination ntawm C-terminus) tshwj xeeb yog pom zoo kom nce tus nqi zoo.

2. Ua kom luv lossis ua kom ntev ntawm qhov sib lawv liag

Qee cov kab ke muaj ntau cov hydrophobic amino acids, xws li Trp, Phe, Val, Ile, Leu, Met, Tyr thiab Ala, thiab lwm yam. Thaum cov hydrophobic residues ntau tshaj 50%, lawv feem ntau tsis yooj yim rau yaj.Tej zaum nws yuav muaj txiaj ntsig los ua kom ntev li ib ntus kom ntxiv qhov zoo thiab qhov tsis zoo ntawm cov peptide.Qhov kev xaiv thib ob yog txo qis qhov luaj li cas ntawm cov saw peptide kom nce qhov zoo thiab qhov tsis zoo los ntawm kev txo qis cov hydrophobic residues.Qhov muaj zog ntawm qhov zoo thiab qhov tsis zoo ntawm cov saw peptide, qhov ntau dua nws yuav hnov ​​​​mob nrog dej.
3. Muab tso rau hauv cov dej-soluble residue
Rau qee qhov peptide chains, kev sib xyaw ntawm qee qhov zoo thiab tsis zoo amino acids tuaj yeem txhim kho cov dej solubility.Peb lub tuam txhab pom zoo kom N-terminus lossis C-terminus ntawm acidic peptides ua ke nrog Glu-Glu.N lossis C qhov kawg ntawm cov peptide yooj yim tau muab thiab tom qab ntawd Lys-Lys.Yog tias pawg them nqi tsis tuaj yeem muab tso rau, Ser-Gly-Ser tuaj yeem muab tso rau hauv N lossis C terminus.Txawm li cas los xij, txoj hauv kev no tsis ua haujlwm thaum ob sab ntawm peptide saw tsis tuaj yeem hloov pauv.