Akwai nau'ikan peptides na transmembrane da yawa, kuma rarrabuwar su ya dogara ne akan kaddarorin jiki da na sinadarai, tushe, hanyoyin ingestion, da aikace-aikacen likitanci.Dangane da kaddarorinsu na zahiri da sinadarai, peptides masu shiga membrane za a iya kasu kashi uku: cationic, amphiphilic da hydrophobic.Cationic da amphiphilic membrane masu shiga peptides suna da kashi 85%, yayin da membrane hydrophobic ke shiga peptides yana da kashi 15%.
1. Cationic membrane shiga peptide
Cationic transmembrane peptides sun ƙunshi gajerun peptides masu wadata a cikin arginine, lysine, da histidine, kamar TAT, Penetratin, Polyarginine, P22N, DPV3 da DPV6.Daga cikin su, arginine ya ƙunshi guanidine, wanda zai iya haɗuwa da hydrogen tare da ƙungiyoyin phosphoric acid da ba su da kyau a kan membrane tantanin halitta kuma ya daidaita peptides transmembrane a cikin membrane a ƙarƙashin yanayin darajar PH.Nazarin oligarginine (daga 3 R zuwa 12 R) ya nuna cewa ikon shigar da membrane yana samuwa ne kawai lokacin da adadin arginine ya kasance ƙasa da 8, kuma ikon shigar da membrane a hankali ya karu tare da karuwar adadin arginine.Lysine, ko da yake cationic kamar arginine, ba ya ƙunshi guanidine, don haka idan ya kasance shi kaɗai, ingancin shigar da membrane ba ya da yawa.Futaki et al.(2001) ya gano cewa za a iya samun sakamako mai kyau na shigar cikin membrane kawai lokacin da membrane na cationic cell da ke shiga peptide ya ƙunshi akalla 8 ingantaccen caja na amino acid.Duk da cewa ragowar amino acid masu inganci suna da mahimmanci ga peptides masu shiga ciki don shiga cikin membrane, sauran amino acid suna da mahimmanci daidai, kamar lokacin da W14 ya canza zuwa F, ikon penetrability na Penetratin ya ɓace.
Wani nau'i na musamman na peptides na cationic transmembrane shine jeri na yanki na nukiliya (NLSs), wanda ya ƙunshi gajerun peptides masu arziki a cikin arginine, lysine da proline kuma ana iya jigilar su zuwa tsakiya ta hanyar hadaddun pore na nukiliya.Ana iya ƙara NLSs zuwa bugu ɗaya da biyu, wanda ya ƙunshi gungu ɗaya da biyu na ainihin amino acid, bi da bi.Misali, PKKRKV daga simian virus 40(SV40) bugu guda NLS ne, yayin da furotin Nukiliya nau'in NLS ne na biyu.KRPAATKKAGQAKKL shine ɗan gajeren jeri wanda zai iya taka rawa a cikin membrane transmembrane.Saboda yawancin NLSs suna da lambobin cajin ƙasa da 8, NLSs ba su da inganci transmembrane peptides, amma suna iya zama ingantattun peptides transmembrane lokacin da haɗin gwiwa tare da jerin peptide hydrophobic don samar da peptides na amphiphilic transmembrane.
2. Amphiphilic transmembrane peptide
Amphiphilic transmembrane peptides sun ƙunshi yanki na hydrophilic da hydrophobic, waɗanda za a iya raba su zuwa amphiphilic na farko, na biyu α-helical amphiphilic, β-folding amphiphilic da prolin-enriched amphiphilic.
Primary type amphiphilic sa membrane peptides cikin nau'i biyu, category tare da NLSs covalently alaka da hydrophobic peptide jerin, kamar MPG (GLAFLGFLGAAGSTMGAWSQPKKKRKV) da Pep - 1 (KETWWETWWTEWSQPKKRKV), Dukansu dogara ne a kan nukiliya localization siginar PKKKRKV, wanda a cikin SV44 hydrophobic sigina. yanki na MPG yana da alaƙa da jerin fusion na HIV glycoprotein 41 (GALFLGFLGAAGSTMG A), kuma yankin hydrophobic na Pep-1 yana da alaƙa da gungu mai arzikin tryptophan tare da babban kusancin membrane (KETWWET WWTEW).Koyaya, yankunan hydrophobic na duka biyu suna da alaƙa da siginar gano makaman nukiliya PKKKRKV ta hanyar WSQP.Wani nau'in peptides na amphiphilic transmembrane na farko an ware shi daga sunadaran halitta, kamar pVEC, ARF (1-22) da BPrPr (1-28).
Na biyu na α-helical amphiphilic transmembrane peptides suna ɗaure ga membrane ta hanyar α-helices, kuma ragowar amino acid hydrophilic da hydrophobic suna samuwa akan sassa daban-daban na tsarin helical, kamar MAP (KLALKLALK ALKAALKLA).Don beta peptide nadawa nau'in amphiphilic wear membrane, ikonsa na samar da takardar beta mai laushi yana da mahimmanci ga ikon shigarsa na membrane, kamar a cikin VT5 (DPKGDPKGVTVTVTVTVTGKGDPKPD) a cikin binciken ikon shigar da membrane, ta amfani da nau'in D. - analogues maye gurbi na amino acid ba zai iya samar da yanki mai naɗewa na beta ba, ikon shigar da membrane ba shi da kyau sosai.A cikin peptides na amphiphilic transmembrane mai wadatar proline, ana samun sauƙin samar da polyproline II (PPII) a cikin ruwa mai tsabta lokacin da proline ke haɓaka sosai a cikin tsarin polypeptide.PPII helix ne na hannun hagu tare da ragowar amino acid 3.0 a kowace juzu'i, sabanin daidaitaccen tsarin alpha-helix na hannun dama tare da ragowar amino acid 3.6 a kowane juzu'i.Proline-enriched amphiphilic transmembrane peptides sun hada da bovine antimicrobial peptide 7 (Bac7), roba polypeptide (PPR) n (n iya zama 3, 4, 5 da 6), da dai sauransu.
3. Hydrophobic membrane shiga peptide
Hydrophobic transmembrane peptides sun ƙunshi ragowar amino acid marasa iyaka, tare da cajin gidan yanar gizon ƙasa da 20% na jimlar cajin jerin amino acid, ko kuma sun ƙunshi ƙungiyoyin hydrophobic ko ƙungiyoyin sinadarai waɗanda ke da mahimmanci ga transmembrane.Kodayake ana yin watsi da waɗannan peptides na transmembrane na salula, suna wanzu, irin su fibroblast girma factor (K-FGF) da fibroblast girma factor 12 (F-GF12) daga Kaposi's sarcoma.
Lokacin aikawa: Maris 19-2023