Protein complex: ukuzimisela, ukwakheka, isakhiwo, isakhiwo, imisebenzi, ngokuhlelwa kwabalinganiswa. Yintoni umahluko iiproteni olula complex?

A protein esimbaxa, ngaphandle icandelo protein ngokwayo luyinto iqela eyongezelelweyo uhlobo ezahlukeneyo (angoozenzele). Njengoko eli candelo are carbohydrate, lipids, isinyithi, elwa phosphoric acid, nucleic acid. Yintoni umahluko iiproteni olula entsokothileyo, ngoko iintlobo wahlula ezi zinto, yaye ziziphi iimpawu zabo, eli nqaku liza kukuxelela. Umehluko omkhulu phakathi izinto ekuthethwa - ukwakhiwa kwawo.

iiproteni Complex: Inkcazo

Le nto-candelo ezimbini, eziquka iprotini elula (imixokelelwane peptide) kunye nezinto non-proteinaceous (iqela angoozenzele). Xa inkqubo haydrolisis acid akhiwa, kwaye non-protein inxalenye iimveliso yokubola. Yintoni umahluko iiproteni olula complex? Eyokuqala ibandakanya kuphela asidi acid.

Ulwahlulo kunye abalinganiswa kweziyi ezimbaxa

Ezi zinto ke zohlulwa ngokwendidi ngokuxhomekeke kuhlobo amaqela ezongezelelweyo. Kuba iiproteni complex ziquka:

• Glycoproteins - iiproteni, iimolekyuli apho i moiety ekudleni. Phakathi kwazo proteoglycans (components isithuba intercellular), kuqukwa mucopolysaccharides yayo isakhiwo. Kuba immunoglobulins are glycoproteins.
• Lipoproteins ziquka isakhi lipid. Ezi ziquka apolipoproteins, enza umsebenzi yokuqinisekisa yothutho lipid.
• Metalloproteins ziqulathe ion yesinyithi (nobhedu, manganese, intsimbi, njalo-njalo), Linked nge intsebenziswano donor-acceptor. Eli qela ayibandakanyi iiproteni heme eziquka profirinovogo ring compound nentsimbi, kwaye babunjani isakhiwo compound (ngokuba yiklorofili, ingakumbi).
• Nucleoproteins - iiproteni ukuba iibhondi non-covalent nee-asidi acid (DNA, RNA). Ezi ziquka chromatin - licandelo zofuzo.
• 5. Fosfoproteidy, eziquka casein (esimbaxa protein curd) ziquka iintsalela covalently esiqhagamshelwe phosphoric acid.

• Chromoproteins kombala esihlanganisa component angoozenzele. Le iklasi iquka iiproteni heme, chlorophylls kunye flavoproteins.

Iimpawu glycoproteins kunye proteoglycans

Ezi proteni izinto ezintsonkothileyo. Proteoglycans ibe iqhezu enkulu wekhabohayidreyiti (80-85%), isiqulatho glycoprotein eqhelekileyo yi 15-20%. asidi Uronic akhona kuphela proteoglycans molecule, carbohydrate bahluke ngeeyunithi zabo rhoqo isakhiwo ephindaphindayo. Yintoni isakhiwo umsebenzi iiprothini ezintsonkothileyo, glycoproteins? imixokelelwane yabo ekudleni iquka iiyunithi-15 kuphela yaye isakhiwo ezitenxileyo ezinokwenzeka. Izithinteli ekudleni of glycoproteins zonxibelelwano kunye icandelo protein i ngokuqhelekileyo nge kwiintsalela acid acid ezifana serine okanye asparagine.

Imisebenzi ye glycoproteins:

• Ziyingxenye eludongeni iseli ziibhakteriya, ithambo kwizicwili kunye intlala, collagen zingqonge ezi Imicu elastin.
• Dlala indima olukhuselayo. Umzekelo, oku isakhiwo omzimba, interferon, izinqumisi igazi (prothrombin, lwefibrinogen).
• Ngaba ezenza banxibelelane effector - encinane molecule non-protini. Ekugqibeleni, ukujoyina i protein, kukhokelela utshintsho Ukumila wayo, nto leyo ekhokelela ukuba impendulo ethile intracellular.
• Yenza umsebenzi hormone. Libhekisela glycoprotein gonadotropin, lengqula-ekuvuseleleni hormone kunye adrenocorticotropic.
• Iziyobisi uthuthwa egazini kunye ion kwi iseli inwebu (transferrin, transcortin, albumin, Na +, K + -ATPase).

Xa glycoprotein enzyme ziquka cholinesterase kunye nuclease.

Okunye proteoglycans

protein entsonkothileyo proteoglycan Ngokuqhelekileyo iquka kubume enkulu chain yayo carbohydrate kunye ukuphindaphinda iintsalela disaccharide kuqulethe uronic acid kunye aminosugar. Oligo- okanye polysaccharide imixokelelwane ebizwa glycans. Eyokuqala adla iiyunithi monomer 2-10.

Kuxhomekeka isakhiwo eentsontelo carbohydrate cell iintlobo zazo ezahlukeneyo, umz, heteropolysaccharides emuncu kunye namaqela emuncu ngakumbi okanye glycosaminoglycan equlethe amaqela acid. Le yokugqibela ziquka:

• Hyaluronic acid, nto leyo eli asetyenziswe zokuthambisa.
• LweeHedfowuni, engakuvumeliyo ekunqandeni igazi.
• Keratan sulfate - amacandelo intlala kunye inwebu.
• sulfates Chondroitin ziyingxenye intlala neencindi synovia.

Ezi Iipholima - amacandelo proteoglycan ukuba ligcwalise isithuba intercellular, iyawagcina amanzi, kuthambisa iindawo ezihambisekayo namalungu, kuba kumacandelo abo zesakhiwo. Hydrophilicity (ukunyibilika elungileyo emanzini) proteoglycans ivumela kuzo kwisithuba intercellular ukwenza umqobo kwiimolekyuli ezinkulu ezincane. Ngoncedo lwabo ukudala matrix gelled apho Imicu iGqili ezinye iiprothini ebalulekileyo, ezifana collagen. bands akhe bume proteoglycan kufuneka imilo emthini.

Iimpawu neendidi lipoproteins

Lipoprotein protein esimbaxa yohlobo esibamba kwaye hydrophobic ezimbini abuthethileyo kakuhle. Kwemolekyuli ezingundoqo (inxalenye hydrophobic) zenze esters non-polar cholesterol kunye triacylglycerides.

Ngaphandle kwindawo esibamba amalungiselelo protein inxenye, phospholipids, cholesterol. Kukho iintlobo ezininzi lipoproteins iiprothini ngokuxhomekeke kwisakhiwo sabo.

Iiklasi ezinkulu lipoproteins:

• Zobunewu protein ache (iHDL, α-lipoprotein). Isa cholesterol kwesibindi nezihlunu neuropathy.
• ingxinano Low (LDL, β-lipoproteins). Ukongezelela cholesterol ithuthwa triacylglycerides kunye phospholipids.
• Kakhulu ingxinano ephantsi (VLDL, pre-β-lipoprotein). Yenza umsebenzi ofanayo ukuya LDL.
• Chylomicrons (CM). Ohambisa okunamafutha acid kunye cholesterol ukusuka emathunjini emva ekudleni.

ngezifo semithambo ezifana kwemithambo yegazi, olubangelwa umlinganiselo ngokungafanelekanga kweentlobo ezahlukeneyo lipoproteins egazini. Xa abalinganiswa ye ubume nga kutyhilwa eziliqela utshintsho iintsingiselo phospholipids structure (ukusuka HDL ukuya chylomicron): ukunciphisa inani leeprothini (80 ku-10%), kunye phospholipids, triacylglycerides ipesenti ukunyuka (20 to 90%).

Phakathi ezininzi ezibalulekileyo enzyme, metalloproteins

Metalloproteins kungaquka ion ezininzi metal. phambi kwabo kuchaphazela yokuqhelwaniswa zeendawana kwi (zokuphosa) site elikhutheleyo enzyme. Metal ion ibekwe kwisiza uze udlale indima ebalulekileyo basabela encedisa ukuqalisa imisebenzi. ion rhoqo lisebenza njenge acceptor electron.

Imizekelo zesinyithi equlethwe kwisakhiwo enzyme metalloproteins:

• Copper idityanisiwe oxidase cytochrome, leyo, kunye heme iqulethe ion yale ngentsimbi. I-enzayim ababandakanyekayo ekubunjweni ATP kwi-chain sokuphefumla.
• Iron ibe enzyme ezifana ferritin, intsimbi owenza umsebenzi sokudipozithwa kwisisele; transferrin - yenethiwekhi yentsimbi egazini; catalase abasabela inoxanduva neutralization hydrogen peroxide.
• Zinc - metal, nto leyo luphawu ukuba utywala inxaxheba igcwala-ethanol kunye alkoholi efanayo; dehydrogenase zincancise - enzyme kwi nethe lactic acid; anhydrase గుర్తులు ibhaloni leyo catalyzes ukuyilwa asidi evela CO ₂ no H ₂ O; phosphatase awana, wenza cleavage hydrolytic of esters phosphate kunye iikhompawundi ezahlukeneyo; α2-macroglobulin - Iprothini igazi antiproteazny.
• Selenium yinxalenye thyroperoxidase inxaxheba ekubunjweni hormone; glutathione peroxidase, njengesikhali umsebenzi antioxidant.
• Calcium obonakaliswa ukuba isakhiwo α-amylase - transcriptase hydrolytic cleavage istatshi.

phosphoprotein

Inxalenye kwiproteni phosphoprotein enzima? Ngokuba lo mqathango luphawulwa ebusweni iqela phosphate, nto leyo kunxulunyaniswa moiety protein nge iasidi acid kunye neqela hydroxyl (tyrosine, serine okanye threonine). Ntoni phosphoric acid, lo gama kungathi ukuba isakhiwo iproteni? Itshintsha isakhiwo molecule, ngokunika umthetho nje, kwandisa ukunyibilika, ichaphazela iimpawu kwiproteni. Imizekelo ubisi phosphoprotein casein kunye iqanda albumin, kodwa ubukhulu becala udidi iiproteni ezintsonkothileyo aba enzymes.

iqela phosphate kudlala indima ebalulekileyo ezisebenzayo, njengoko iiproteni ezininzi ezinxulumene nayo akukho ngokusisigxina. Endlwaneni kwiinkqubo lonke ixesha phosphorylation kunye dephosphorylation zenzeka. Ngenxa yoko, mmiselo oluqhutywa iiproteni. Umzekelo, ukuba histones - proteins ezinxulumene nucleic asidi ingeniso ngokwaseburhulumenteni phosphorylated, ngoko ke umsebenzi zofuzo (i-genetic material) kwandisa. Xa phosphorylation kuxhomekeke umsebenzi enqanda ezifana glycogen synthase kunye glycogen phosphorylase.

nucleoprotein

Nucleoproteins - iiproteni ezinxulumene asidi acid. Yokuba - yinxalenye ukugcinwa kunye nokulawulwa kwezixhobo yemfuza, umsebenzi ribosomes, ukwenza umsebenzi protein yokuqaphela. Ifomu elula ubomi abanentsholongwane kuthiwe ribo- kunye dezoksiribonukleoproteinami, ekubeni kuba genetic material kunye neeproteni.

Njengoko intsebenziswano of deoxyribonucleic acid (DNA) kunye histone? Xa chromatin bodwa ezimbini iintlobo iiprotheni ezinxulumene ne-DNA (histone and non-histone). Inyathelo lokuqala ababandakanyekayo ukugangatheka wokuqala DNA. nucleic acid molecule ijijekileyo malunga iiproteni ukwenza nucleosomes. Kumsonto kwakhiwa uyafana amaso, akhiwa isakhiwo supercoiled (chromatin fibril) kunye supercoil (genonema interphase). Yintshukumo iiprothini histone kunye neeproteni ze kumanqanaba aphezulu inika ukwehliswa Ubukhulu DNA amawaka amaxesha. Lwanele ukuthelekisa ubungakanani chromosome kunye nobude asidi acid, ukuvavanya ukubaluleka iiprothini (6-9 cm kunye 6.10 microns, ngokulandelelanayo).

Yintoni chromoproteins

Chromoproteins ziqulathe amaqela ahlukeneyo kakhulu abo bamanyene kuphela enye into - ubukho umbala kwi candelo angoozenzele. iiproteni Complex kolu didi yahlulwe: hemoproteins (ziqulathe isakhiwo heme) retinalproteiny (vitamin A), flavoproteins (vitamin B2), kobamidproteiny (vitamin B12).

Hemoproteins zahlelwa ngokuvumelana nemisebenzi kwi non enzymatic (mioglobinovy haemoglobin kunye protein) kunye nee-enzayim (cytochromes, catalases, peroxidases).

Flavoproteins ibe njengoko avela component prosthetic uvitamin B2, flavin mononucleotide (FMN) okanye flavin dinucleotide adenine (zokunciphisa). Ezi enzyme ayabandakanyeka zinguquko redox. Ezi ziquka oxidoreductases.

Yintoni cytochromes?

Njengoko kuchaziwe ngentla, nto ibandakanya heme porphyrin. isakhiwo layo ngumxube amakhonkco amane pyrrole, kunye nentsimbi divalent. Iqela elikhethekileyo enqanda heme - cytochromes, ezahlukeneyo kwi acid acid Ukwakhiwa kunye nenani xo peptide, olulodwa ekuqhubeni indlela redox, ngenxa apho ibonelelwa transfer electron kwi kwikhonkco sokuphefumla. Ezi enzyme zinenxaxheba microsomal igcwala - ngayo zokuqala biotransformation xenobiotic, okukhokelela zavunyelwa yabo yokucolwa kwezinto ezininzi zemveli kunye zithe zadala, ezifana steroids, fatty ifumile.

Effect iqela zokufakelwa

iqela Prosthetic, nto leyo eyinxalenye protein esimbaxa kuchaphazela iimpawu zayo: ukutshintsha isigxina yayo, ukunyibilika, thermoplasticity. Umzekelo, isenzo esinjalo kufuneka iintsalela phosphoric acid okanye monosaccharides. Inxalenye ekudleni zibandakanyiwe entsonkothileyo kwiproteni, awukhusele proteolysis (kutshatyalaliswa haydrolisis) ichaphazela kwii-iimolekyuli ngokusebenzisa inwebu yeseli, secretion lwabo nokulungisa. Le moiety lipid ivumela neprothini ukudala amajelo ukuthuthwa kakubi awonayo lwamanzi iikhompawundi (hydrophobic).

Isakhiwo kunye nomsebenzi iiproteni ezintsonkothileyo ixhomekeke ngokupheleleyo kwi qela angoozenzele. Umzekelo, usebenzisa heme yentsimbi aqulethe oksijini haemoglobin esibophelelayo kwenzeka kunye carbon dioxide. Ngenxa nucleoproteins akhiwa impefumlelwano histones, protamines kunye DNA okanye RNA kwenzeka ukukhusela izinto yemfuza, ukugcinwa yayo compact, inkqubo nomphetho owujikelezileyo RNA ngakwicala leeprothini yokuqaphela. Nucleoproteins wabiza izakhiwo ezizinzileyo kweziyi kunye nucleic.

isiphelo

Ngenxa yoko, iiprotheni complex sezineentlobo enkulu imisebenzi emzimbeni. Ngoko ke, ukusetyenziswa olukhulu kunye Izakha kubaluleke kangaka impilo. Iintsimbi ziyingxenye enqanda ezininzi. Ukwazi eziphilayo, ingakumbi impilo kunye nobume yendalo yokuhlala, uyakwazi ukunyenyisa indlela amandla ayo. Umzekelo, intsimi ekwanti, esibonakala ukuswela i element. kokungena kwakhe ezongezelelweyo yokudla ngohlobo kwezithako kuvumela ukubuyekeza ukuswela.