Yaya ƙa'idar ƙirƙirar haɗin peptide ke cikin haɗin al'ada na peptide?

A saman, samuwar peptide bond, samar da dipeptides, wani tsari ne mai sauƙi na sinadarai.Wannan yana nufin cewa sassan amino acid guda biyu suna haɗe ta hanyar haɗin peptide, haɗin amide, yayin da ake bushewa.

Samuwar haɗin Peptide shine kunna amino acid a ƙarƙashin yanayi mai sauƙi.(A) carboxyl moiety, amino acid na biyu (B) Motsin carboxyl da ke kunna nucleophilic sannan ya samar da dipeptide (AB)."Idan ba a kiyaye bangaren carboxyl (A) ba, ba za a iya sarrafa samuwar peptide bond ba."Samfuran irin su peptides na layi da cyclic ana iya haɗa su tare da mahaɗan AB.Don haka, duk ƙungiyoyin aiki waɗanda ba su da hannu a cikin samuwar haɗin peptide dole ne a kiyaye su ta wani ɗan lokaci mai jujjuyawa yayin haɗuwar peptide.

Don haka, kira na peptide - samuwar kowane haɗin peptide - ya ƙunshi matakai uku na haɗuwa.

Mataki na farko shine shirya wasu amino acid waɗanda ke buƙatar kariya, kuma tsarin zwitterionic na amino acid ya daina wanzuwa.

Mataki na biyu shine amsa mataki biyu don samar da peptide bonds, wanda ƙungiyar carboxyl na amino acid mai kariya ta N aka fara kunnawa zuwa tsaka-tsaki mai aiki sannan kuma haɗin peptide ya kasance.Wannan haɗin gwiwar na iya faruwa ko dai a matsayin amsa ta mataki ɗaya ko azaman halayen jeri biyu.

Mataki na uku shine zaɓin cirewa ko cikakken cire tushen kariya.Ko da yake duk cirewa zai iya faruwa ne kawai bayan an haɗa dukkan sarƙoƙi na peptide, ana kuma buƙatar cire zaɓi na ƙungiyoyin kariya don ci gaba da haɗin peptide.

 肽键2

Domin amino acid 10 (Ser, Thr, Tyr, Asp, Glu, Lys, Arg, His, Sec da Cys) sun ƙunshi ƙungiyoyin aiki na sassan sassan gefe, waɗanda ke buƙatar kariya ta zaɓi, yana sa haɗin peptide ya fi rikitarwa.Dole ne a bambanta sansanonin kariya na wucin gadi da na dindindin saboda buƙatun daban-daban don zaɓin zaɓi.Ana amfani da ƙungiyoyin kariya na wucin gadi a mataki na gaba don nuna kariya ta wucin gadi na amino acid ko ƙungiyoyin aikin carboxyl.Ana cire ƙungiyoyin kariya na dindindin ba tare da tsoma baki tare da riga-kafi na peptide bond ko sarƙoƙin gefen amino acid ba, wani lokacin yayin haɗuwa.

"Da kyau, kunna bangaren carboxyl da kuma samuwar peptide bonds (haɗin haɗin kai) yakamata ya kasance cikin sauri, ba tare da haɓakar tseren tsere ba, kuma yakamata a yi amfani da reactants don cimma babban sakamako."Abin baƙin ciki shine, babu ɗayan hanyoyin haɗin sinadarai da suka cika waɗannan buƙatu, kuma kaɗan ne suka dace da haɗin kai.

 肽键3

A lokacin haɗin peptide, ƙungiyoyi masu aiki da ke cikin halayen daban-daban yawanci ana danganta su zuwa cibiyar jagora, glycine shine kawai banda, kuma akwai yiwuwar juyawa.

Mataki na ƙarshe a cikin sake zagayowar kirar peptide shine kawar da duk ƙungiyoyin kariya.Zaɓin cire ƙungiyoyin kariya yana da mahimmanci don haɓaka sarkar peptide ban da buƙatun gabaɗayan kawar da kariya a cikin haɗin dipeptide.Ya kamata a tsara dabarun roba a hankali.Dangane da zaɓin dabara, N na iya zaɓin cire α-amino ko ƙungiyoyin kariya na carboxyl.Kalmar “dabaru” tana nufin jerin halayen amino acid guda ɗaya.Gabaɗaya, akwai bambanci tsakanin haɗawa da sannu-sannu da gutsuttsura.Peptide kira (wanda kuma aka sani da "haɗin kai na al'ada") yana faruwa a cikin bayani.A mafi yawan lokuta, tsawaita sarkar peptide a hankali za a iya haɗa ta ta amfani da sarkar peptide don haɗa guntun guntu.Don haɗa peptides masu tsayi, dole ne a rarraba ƙwayoyin da aka yi niyya zuwa gaɓoɓin da suka dace kuma a ƙaddara cewa za su iya rage girman bambance-bambance a ƙarshen C.Bayan an tattara guntuwar guda ɗaya a hankali, za a haɗa mahaɗin da aka yi niyya sama.Dabarar haɗin gwiwar peptide ya haɗa da zaɓin mafi kyawun ɓangarorin kariya mafi kyau kuma mafi dacewa, kuma dabarun haɗin gwiwar peptide ya haɗa da zaɓin mafi kyawun haɗin haɗin tushe na karewa da mafi kyawun hanyar haɗakarwa.


Lokacin aikawa: Jul-19-2023