Iiproteni: Ulwakhiwo kunye nomsebenzi iiprothini

Proteni izinto eziphilayo. Ezi zihlanganisi macromolecular luphawulwa sisincoko ethile kunye haydrolisis cazulula zibe asidi acid. iimolekyuli protein unokuba iimilo ezahlukeneyo, abaninzi kubo luqulathe ngemixokelelwane eziliqela polypeptide. Ulwazi malunga isakhiwo kwiproteni okubhalwe kule DNA, kunye neprothini iimolekyuli inkqubo yokuqaphela ebizwa translation.

Le khemikhali Ukubunjwa iiprotheni

Umlinganiselo protein iqulethe:

• 52% carbon;
• 7% hydrogen;
• 12% nitrogen;
• 21% oxygen;
• 3% nesalfure.

iimolekyuli protein - are neeplastikhi. Ukuze ukuqonda isakhiwo, kufuneka ukuba uyazi ukuba yintoni eyenza monomers zabo - acid.

acid

Bangakwazi zingahlulwa ngokweendidi ezimbini: ezenzeka rhoqo kwaye ngamanye amaxesha nazo. Le yokuqala inkqubo yona ibonelela 18 protein monomers amide 2: aspartic acid kunye glutamic acid. Ngamanye amaxesha kukho amathathu kuphela asidi.

Ezi asidi nga zihlelwe ngeendlela ezahlukeneyo: uhlobo eentsontelo kwicala okanye wabayala radicals, nayo zingakotshwa lahlulwe ngenani kwamaqela, CN kunye COOH.

Isakhiwo ephambili kwiproteni

Umyalelo acid kwikhonkco iproteni imisela imigangatho yaso emva koko lombutho, iimpawu kunye nemisebenzi. Eyona uhlobo lonxibelelwano phakathi monomers is a peptide. It ukhandwa ukususwa hydrogen ukusuka aminoksloty omnye OH neqela elinye.

Inqanaba lokuqala kwintlangano kwiproteni molecule - ukulandelelana asidi acid kuyo, nje umxokelelwane, nto leyo ebonisa ubume iimolekyuli protein. Siqulathe "amathambo" ukuba isakhiwo rhoqo. Le ulandelelwano ngokuphindaphindiweyo -NH-CH-NGEZEKHARITYHULAM. radicals neentsontelo icala ethile ye asidi acid zinikwa (R), iimpawu zabo amisele ukwakhiwa kobume protini.

Nokuba isakhiwo esifanayo molecule ye iiprotheni, nokuba bohluka yi kuphela kwiipropati abe ulandelelwano ezahlukeneyo monomers kwi kwikhonkco. Umyalelo we acid kwi iproteni umiselwa izakhi kunye iproteni bumisela imisebenzi ethile eziphilayo. Ngokulandelelana monomers kwi molekyuli unoxanduva umsebenzi ofanayo, kufutshane ngokufuthi kwiintlobo ezahlukeneyo. molecule anjalo - efanayo okanye ezifanayo ukuhlela enze kwiintlobo ezahlukeneyo eziphilayo, umsebenzi ofanayo - iiproteni homologous. Isakhiwo, iimpawu kunye nemisebenzi iimolekyuli elizayo babekwa kwi nqanaba Yindibanisela ngemixokelelwane asidi acid.

Ezinye iimpawu ezifanayo

Ubume kwiproteni sele efunde ixesha elide, kunye nocazululo lwabo lokuqala isakhiwo ukuba sikwazi ukwenza ezinye nentetho equkayo. Ngokuba inani elikhulu kwiiproteni luphawulwa ebusweni bonke amabini asidi acid, apho glycine lilikhulu, alanine, aspartic acid, glutamine kunye tryptophan encinane, arginine, methionine, histidine. Ngaphandle amaqela nje ezimbalwa iiprotheni, ezifana histones. Bona eziyimfuneko DNA ezingxobeni ziqulathe eninzi histidine.

Le gabalala yesibini: Akukho iipateni eziqhelekileyo acid kwi alternation kweziyi globular. Kodwa kumsebenzi ekude bemvelo polypeptides zibe ngamaqhekeza amancinci ezo molekyuli efanayo.

isakhiwo secondary

Inqanaba lesibini lombutho chain polypeptide - isikhundla sayo lomhlaba, apho igcinwa yi kwiintambo hydrogen. Cell α-kweleli kunye β lunemiba. Abaphathi beesekethe inxenye kuye isakhiwo wayalela, iindawo ezinjalo kuthiwa amorphous.

Alpha-kweleli kweziyi pravozakruchennaya zendalo. amaqela Icala acid kwi kweleli soloko lijonge ngaphandle kwaye ibekwe akumacala axis yayo. Ukuba non-polar, kukho iqela kwelinye icala kweleli wafumana arc, eyenza i iimeko ukuze ukuhlangabezana kwiingingqi ezahlukeneyo helical.

Beta-lunemiba - kweleli side kakhulu - bakholisa ukuhlala kwemolekyuli protein benziwa kufutshane kwaye ingqamene ungqameko β-elincane ezingezo-ngaxeshanye.

Isakhiwo neliphezulu protini

Inqanaba lesithathu lombutho le protini molecule - ngokusonga ahamba, nezibaya nemimandla amorphous kwisakhiwo compact. Oku kwenzeka ngenxa intsebenziswano phakathi iintsontelo icala monomers ngokwabo. Amakhonkco ezinjalo zohlulwa ngokwendidi ezininzi:

• iibhondi hydrogen kwakheka phakathi radicals polar;
• Hydrophobic - phakathi non-polar R-amaqela;
• electrostatic amabutho enomtsalane (iibhondi ionic) - phakathi kwamaqela, izityholo leyo malungana;
• iibhulorho disulfide - phakathi radicals cysteine.

Uhlobo yokugqibela lonxibelelwano (-S = S-) imele covalent intsebenziswano. iibhulorho Disulfide ukuqinisa iiproteni, isakhiwo liba womelele ngakumbi. Kodwa ubukho amakhonkco ezinjalo akumenzi ngokuyimfuneko. Umzekelo, cysteine inokuba encinane kakhulu kwikhonkco polypeptide, okanye radicals apha kwaye akakwazi ukwenza i "ibhulorho".

Inqanaba lesine bombutho

isakhiwo koqeqesho ibunjiwe, hayi zonke iiprothini. Ubume bale kwiiproteni kumgangatho wesine emiselwe inani imixokelelwane polypeptide (protomers). Bona kwadityaniswa yi unxulumano efanayo njengoko inqanaba yangaphambili yombutho, ukongeza disulfide imizila. Le molecule iquka inani protomers, ngamnye kubo ezizodwa (okanye twatse) isakhiwo yayo ephakamileyo.

Onke amanqanaba eziko ukuqinisekisa iimpawu eziza kukhonza ukufumana protein. Ubume kwiproteni kwinqanaba lokuqala mbutho ngokuchanileyo kakhulu imisela indima yabo emva esiseleni kunye nenyama xa iyonke.

Imisebenzi ye iiprotheni

Kunzima ukucinga indlela ebalulekileyo indima kwiiproteni kumsebenzi yeseli. Ngaphezu sakukhangelayo isakhiwo zabo. Imisebenzi iiproteni zixhomekeke ngqo kulo.

Ukwenza isakhiwo (kwesakhiwo) umsebenzi, bakha isiseko salo naliphina kukho icytoplasm yeseli ophilayo. Ezi Iipholima ezi izinto ezingundoqo zonke imifinya iseli, xa obandakanywa a nezintsonkothileyo lipids. Oku kuquka iseli candelo kwiindawo, iyileyo zenzeke ngayo zabo. Le nto yokuba kufuneka yawo, indima ebaluleke kakhulu edlalwa pH medium ngokuthi nganye iinkqubo ezintsonkothileyo cellular. Iiproteni ukwakha iindonga ezingcakacileyo, leyo kokwaba iseli ebizwa ngokuba yi-amagumbi. Kodwa isenzeko sele kuthiwa compartmentalization.

Umsebenzi zokuphosa kukulawula zonke ngayo cellular. Zonke enzyme imvelaphi zilula okanye neeproteni ezintsonkothileyo.

Naziphi na iintlobo eziphilayo lwentshukumo (umsebenzi kwezihlunu, intshukumo esiseleni protoplasm, ciliary yokudanyaza kwi lenyama kunye t. D.) Ngaba iiproteni okwenziwa. Ubume kweziyi ivumela ukuba bafudukele kwimicu ifomu kunye namakhonkco. Umsebenzi izithuthi kukuba izinto ezininzi bathuthwayo kuzo iiproteni yenethiwekhi ethile cell ndizayo.

indima hormone yezi Iipholima Iyaqondakala kwaoko; kubume iqela hormone iiprothini, ezifana insulin, yioxytocin.

umsebenzi Ukufakelwa uzimisele ukuze iiproteni bayakwazi ukwenza iidipozithi. Umzekelo, valgumin amaqanda, casein ubisi, iiprotheni zokugcina imbewu sisityalo - inani elikhulu kwezondlo agcinwe khona.

Zonke imisipha, zokucacisa edibeneyo, amathambo amathambo, iimpuphu kwakhiwa iiprotheni, nto leyo izisa ukuba omnye imisebenzi yazo - inkxaso.

iimolekyuli protein ezi receptors ababethwele ingqalelo ukukhetha kwezinto ezithile. Kule ndima, ingakumbi eyaziwa glycoproteins kunye lectins.

Eyona miba ibalulekileyo okukwazi - izilwa-buhlungu kunye nenkqubo ezifunekayo imvelaphi ziiproteni. Umzekelo, inkqubo coagulation igazi isekelwe utshintsho ngakwicala leeprothini lwefibrinogen. Iindonga engaphakathi kuvuleke iminxunya emathunjini ilandelelanisiwe ngomaleko ibakhusela iiprotheni yangaphakathi - Litsinija. Nobumdaka kwakhona iiproteni ngemvelaphi. isiseko eluswini, ekhuselweyo umzimba imfuyo collagen. Yonke le misebenzi ziiproteni zokuzikhusela.

Kaloku, lo wokugqibela umsebenzi kumqolo - yolawulo. Kukho ziiproteni ukulawula umsebenzi ufuzo. Oko kukuthi, ukuba ukulawula umbhalo kanye translation.

Enoba indima ebalulekileyo edlalwa naziphi iiproteni, isakhiwo iiproteins yaba oosonzululwazi unriddled ixesha elide. Kwaye ngoku uvula iindlela ezintsha ukusebenzisa olu lwazi.