Protein: isakhiwo kunye nomsebenzi. iimpawu iiprotheni

Njengoko yaziwa, iiprotheni - isiseko ngemvelaphi ubomi emhlabeni. Ngokutsho kwithiyori Oparin-Haldane yaba drop coacervate, eliquka molecule peptides, liye laba sisiseko imvelaphi yezinto eziphilayo. Oku Akukho mathandabuzo kuba uhlalutyo lwesakhiwo ngaphakathi naliphi na ilungu le-biomass ubonisa ukuba ezi zinto zibe yonke: izityalo, izilwanyana, Cya, nomngundo, iintsholongwane. Kwaye zahlukahlukene kakhulu kwindalo kunye macromolecular.

Amagama kwezi ziseko zine, ukuba kuyahambisana:

• protein;
• protein;
• polypeptides;
• peptides.

iimolekyuli protein

Inani labo mkhulu kakhulu ngokwenene. Kulo mzekelo, zonke ezo molekyuli protein zingahlulwa zibe ngamaqela amabini ezinkulu:

• Simple - kwenziwa kuphela ulandelelwano acid acid uncediswa izitropu peptide;
• complex - Isakhiwo kunye nesakhiwo iproteni luphawulwa amaqela ezongezelelweyo protolytic (zokufakelwa), ekwabizwa ngokuba cofactors.

Kulo mzekelo, ezo molekyuli nazo abe nodidi zabo.

Kwezidalwa peptides complex

1. Glycoproteins - zihlobene enxulumene protein ekudleni kusitsha. Ubume kwemolekyuli womluki amaqela zakhe mucopolysaccharides.
2. Lipoproteins - inamehlo entsonkothileyo protein ne lipid.
3. Metalloproteins - njengeqela zokufakelwa ezi ion yesinyithi (yentsimbi, manganese, nobhedu, kunye nabanye).
4. Nucleoproteins - protein Ingcaciselo nucleic (DNA, RNA).
5. Fosfoproteidy - Ukumila kwe-protein kunye amasalela abantu phosphoric acid.
6. Chromoproteids - efana kakhulu metalloproteins, kodwa isolotya yinxalenye yeqela zokufakelwa kukho elinombala entsonkothileyo (ebomvu - athwala, eluhlaza - yiklorofili, njalo njalo).

Iqela ngalinye kuxoxwa isakhiwo neempawu iiproteni ezahlukileyo. Imisebenzi ukuba enze, kwaye ziya kwahluka ngokuxhomekeke kuhlobo molecule.

Ubume chemical iiprotheni

Ukususela kule mbono iiproteni - ende, nomxokelelwane omkhulu zeentsalela acid acid amaqhina oqhagamshelwano iibhondi ethile ebizwa peptide. Ukususela icala izakhiwo asidi kumka yesebe - radicals. Esi sakhiwo kwemolekyuli yafunyanwa ngama E. Fischer ekuqaleni kwenkulungwane xxi.

Kamva, iiprotheni, isakhiwo kunye nomsebenzi iiprothini ziye kufundwe iinkcukacha ezingaphezulu. Kuye kwacaca ukuba acid okumisele isakhiwo peptide, abangama-20, kodwa ke zidityaniswe ngeendlela ezahlukeneyo. Ngenxa yoko neyantlukwano izakhiwo polypeptide. Ukongeza, kwinkqubo ubomi kunye nokwenziwa kwemisebenzi yayo iiproteni banako ukuba bangenele uthotho zinguquko imichiza. Ngenxa yoko, ukuba utshintshe isakhiwo, kwaye kukho kakhulu uhlobo olutsha lonxibelelwano.

Ukuba ndimaphule iqhina peptide, oko kukuthi, kuphazamise isakhiwo nezo ngemixokelelwane kufuneka zikhethwe iimeko engqongqo kakhulu (amaqondo obushushu aphezulu, acid okanye ialakalin kuvala). Oku kungenxa yokuba amandla eliphezulu le imixokelelwane covalent kwi molecule, oko kukuthi, kwiqela peptide le.

Efumanise isakhiwo iiprothini elabhoratri lwenziwa usebenzisa indlela biuret - ukusebenza ngomhla polypeptide esandula sivete hayidroksayidi, ubhedu (II). Le entsokothileyo qela peptide nobhedu le ion inika violet umbala eliqaqambileyo.

Kukho ezine umbutho basic lwezakhiwo, nganye eneyazo iimpawu yalo ubume iiprothini.

Amanqanaba lombutho: isakhiwo lokuqala

Njengoko kukhankanyiwe ngasentla, le peptide - ukulandelelana zeentsalela acid acid kunye inclusions, co-enzayim, okanye ngaphandle kwazo. Ngoko ukubiza le isakhiwo ephambili kwemolekyuli, leyo ngokwemvelo, Kakade ke, lo ngowona acid lokwenyaniso anamathele ngeentambo peptide, akukho wumbi. Oko kukuthi, ubume polypeptide yomgama. Kule isakhiwo ethile iiproteni ngale ndlela - ukuba Ngokudibanisa le asidi kubalulekile ukuba lenze imisebenzi kwemolekyuli protini. Ngenxa ezi mpawu kunokwenzeka kuphela ukukhangela peptide kodwa ukuqikelela iimpawu kunye nendima entsha ngokupheleleyo, njengokuba kodwa eyay. Imizekelo peptides ekubeni nesakhiwo yokuqala yendalo, - insulin, pepsin, chymotrypsin, kunye nabanye.

Ukumila secondary

Isakhiwo neempawu iiproteni kolu didi iyahluka thile. Loo ukwakheka kuyilwa kuqala kwi uhlobo okanye xa phantsi haydrolisis ephambili engqongqo, ubushushu okanye ezinye iimeko.

Le Ukumila has iintlobo ezintathu:

1. Smooth, rhoqo, imibhijelo stereoregular ezakhiwe kumsi acid acid ukuba ejijekileyo ngeenxa esqwini engundoqo udibaniso. Kuphela zibanjwa kunye ngeentambo hydrogen zisenzeka phakathi iqela oksijini peptide omnye kunye nomnye hydrogen. Sikuyo isakhiwo luchanekile ngenxa yokuba Akubuya ngokulinganayo phindwa yonke level 4. Loo isakhiwo kunokuba zombini elinxele kunye pravozakruchennoy. Kodwa iiproteni ezininzi eyaziwa dextrorotatory abathi isomer. Ukumila eso kuthiwa udibaniso lwe-izakhiwo.
2. Yenziwe ngoobani kunye nolwakhiwo uhlobo protein ilandelayo wahlukile kowangaphambili ukuba ndisezintanjeni hydrogen ukuba ayakhekanga phakathi kwicala emi ecaleni kwelinye icala intsalela kwemolekyuli naphakathi kakhulu isuswe, apho umgama enkulu ngokwaneleyo. Ngenxa yesi sizathu, isakhiwo yonke uba lihlangana ngakumbi, kwalula imixokelelwane inyoka polypeptide. Kukho enye inkalo ekufuneka ibe protini. Ubume bale acid yamasebe kufuneka libe lifutshane ukuba glycine okanye alanine, umzekelo. Olu hlobo Ukumila secondary kuthiwa beta-sheets nekhono lawo lihlale ndawonye ukuba ukuyilwa kobume lulonke.
3. Besive isakhiwo uhlobo iiproteins wesithathu njengoko eziphilayo kubonisa raznorazbrosannye ezintsonkothileyo, amaqhekeza unordered ukuba akukho stereoregularity kwaye ukwazi ukuguqula isakhiwo phantsi kwempembelelo iimeko zangaphandle.

Imizekelo iiprotheni ekubeni nesakhiwo lesibini ngemvelo, akukho kutyhilwa.

imfundo ephakamileyo

Le Ukumila noko esimbaxa, ukuba igama "globule". Yintoni iproteni? Ubume kwayo isekelwe kubume aphakamileyo, kodwa wongezelela iindidi ezintsha leendibano phakathi atom zamaqela, kwaye yonke molecule nezibaya ngathi, bakhokelwe, into yokuba amaqela esibamba ziye bangene globules kunye hydrophobic - out.

Oku kuchaza isigxina kwemolekyuli iiprothini izisombululo colloidal emanzini. Zeziphi iindidi iintsebenziswano apho?

1. iibhondi hydrogen - azitshintshanga phakathi kwezahlulo efanayo kubume ezizisekondari.
2. I hydrophobic (esibamba) intsebenziswano - kuvela xa unyityilikiswa polypeptide emanzini.
3. Umtsalane Ionic - raznozaryazhennymi kuyilwa phakathi kwiintsalela acid acid (olukhulu) amaqela.
4. Covalent angu - ukuze kwakheke phakathi kweziza ezithile asidi - molekyuli cysteine, hayi kanye mandithi, nasemisileni yawo.

Ngoko ke, ngoobani kunye nolwakhiwo iiprothini ukuba isakhiwo ephakamileyo linokuchazwa ngokuthi isongwe phezulu ngemixokelelwane globules polypeptide, kugcinwe kwaye uzinze, Ukumila yayo ngenxa iintlobo ezahlukeneyo leendibano imichiza. Imizekelo peptides ezinjalo: fosfoglitseratkenaza, tRNA, Alpha-zenziwe ngekeratini, isilika fibroin, kunye nabanye.

Isakhiwo koqeqesho

Le yenye yezona enzima globules, leyo fomu iiprothini. Isakhiwo kunye nomsebenzi iiproteni isicwangciso enjalo ubhetyebhetye kwaye ethile.

Yintoni na le Ukumila? Kuyinto ezimbalwa (ngamanye amaxesha amaninzi) amatsheyini polypeptide ezinkulu nezincinane, ezo kwakheka ngokuzimeleyo ngalinye enye. Kodwa ke, ngenxa enye into ehla esiye sayiqwalasela ukuba isakhiwo ephakamileyo yezi peptides ukuba wayedityaniswe munye. Ngaloo wafumana globules ezintsonkothileyo conformational ezinokuba athom otyhidiweyo, kunye namaqela lipid, kunye ekudleni. Imizekelo iiproteni: DNA polymerase, virus icuba imvulophu protein, ihemoglobin, kunye nabanye.

Zonke izakhiwo peptide siye saxubusha kufuneka iindlela zabo lwesazisi elabhoratri, ngokusekelwe amathuba zangoku yokusebenzisa chromatography, centrifugation, electron kunye microscopy ezisebenzisa ubugcisa eliphezulu computer.

imisebenzi

Isakhiwo kunye nomsebenzi iiprothini ngokusondeleyo ngamazinga omnye nomnye. Oko kukuthi, peptide ngalinye lidlala indima ukuba wahlukile kwaye ethile. Kukho abo bakwaziyo ukwenza kwisisele ophilayo, iintengiselwano ezininzi ezibalulekileyo. Kodwa ingashwankathelwa ngale ukuvakalisa imisebenzi esisiseko ye iimolekyuli iiprothini imizimba eziphilileyo:

1. Ukunika traffic. elilodwa okanye organelles, okanye iintlobo ezithile iiseli bayakwazi intshukumo, cuts, iintshukumo. Le iproteni inikezelwa, eziyinxalenye yesakhiwo yabo izixhobo motor: isiliya, misila, ndizayo cytoplasmic. Ukuba sithethe malunga nokungakwazi ukubana iiseli, iiproteni inokuba negalelo ekunciphiseni yazo (myosin kwezihlunu).
2. umsebenzi yesondlo okanye backup. Kuyinto zemali iimolekyuli iiprothini oocytes, imibungu kunye imbewu ngenxa ngakumbi zokuzaliswa ezingekhoyo izondlo. Phezu cleavage le peptides ukuvelisa acid kunye nezinto eziphilayo esebenzayo, eyimfuneko kuphuhliso eqhelekileyo eziphilayo.
3. Umsebenzi namandla. Ngaphandle carbohydrate yamajoni omzimba unako ukuvelisa kunye neeproteni. Xa ekonakaleni kwe-1 g peptide akhululwe 17.6 kJ amandla esiluncedo ngohlobo triphosphate adenosine (ATP), nto leyo ichithwa kwiinkqubo ezibalulekileyo.
4. Uphawu nowolawulo. It iqulathe ekuqhubeni esweni ngenyameko iinkqubo oluqhubekayo kunye ukudluliselwa lwemiqondiso ukusuka kwiseli ukuya izihlunu, kubo kwabasemagunyeni, ukusuka zamvanje kwinkqubo njalo njalo. Omnye wemizekelo yoku-insulin, apho ubhala ngokungqongqo inani glucose kwegazi.
5. umsebenzi receptor. Oku kuphunyezwa ngokuguqula Ukumila kwe peptide kunye kwelinye icala inwebu kunye nenxaxheba kwelinye icala ngokutsha. Xa oku kwenzeka kwaye transmission uphawu kwaye ulwazi olufunekayo. Inkoliso yezi proteni okulungiswe inwebu cytoplasmic eziseleni a endla ntirho ulawulo olungqongqo kulo lonke ngokudlula therethrough eziphathekayo. Kwakhona tufwile ukuba utshintsho yemichiza emzimbeni kokusingqongileyo.
6. umsebenzi yezothutho peptides. Kuliwa uyawondla iiproteni kunye neeproteni umthuthi. Indima yabo izicacele - zithutha iimolekyuli ezinqwenelekayo kwiisayithi kunye enamandla elisezantsi kwiindawo eziphakamileyo. Omnye wemizekelo yoku ukuthuthwa oksijini carbon dioxide amalungu kunye nezihlunu yihemoglobin. Kwakhona baye baphumelela ukuziswa iikhompawundi ezinobunzima molekyuli iphantsi le inwebu kungena kwiseli.
7. umsebenzi Isakhiwo. Enye yezinto ezibalulekileyo abo eyenza protein. Ubume bale iiseli kunye organelles silapha peptides. Bafana ukuya isakhelo ukuchaza imilo kunye nesakhiwo. Ngaphezu koko, nabo iyaxhaswa, okanye uze ulungise xa kuyimfuneko. Ngoko ke, ukukhula kunye nophuhliso zonke izinto eziphilayo iiproteni ayimfuneko ekutyeni. peptides ezinjalo ziquka elastin, tubulin, collagen, actin, kunye nezinye ngekeratini.
8. Umsebenzi encedisa ukuqalisa imisebenzi. Kwakhe ekwenzeni enzyme. Zininzi kwaye zahlukene, ukuba kukhawuleziswe bonke abasabela yemichiza kwemichiza emzimbeni. Ngaphandle inxaxheba yabo, apile eziqhelekileyo esiswini wayeza kukwazi ukuba ukugaya kuphela iintsuku ezimbini, kusenokwenzeka ukuba sigobe ngexesha elifanayo. Phantsi yesenzo catalase, peroxidase kunye nezinye enzayim, le nkqubo lwenzeka ngeeyure ezimbini. Ngokubanzi, kuba ebulela kule ndima, iiproteins anabolism kunye catabolism kuliwa, oko kukuthi, iplastiki kunye namandla ukutya.

Indima yokhuselo

Kukho iintlobo ezininzi umnwe, ukusuka apho iiprotheni ziyilelwe ukuba ukukhusela umzimba.

Okokuqala, ukuhlasela imichiza zonxinzelelo wezenzi, iigesi, iimolekyuli, izinto spectrum ezahlukeneyo amanyathelo. Peptides bayakwazi ukuzibandakanya nabo sokungamelani imichiza, iguqulela kwifomu engenabungozi okanye nje lwaze.

Okwesibini, ugrogriso wenyama inxeba - ukuba kwiproteni lwefibrinogen kwi xesha similise fibrin kwisayithi umdlali olimeleyo, igazi akuthethi curdle, kwaye kungoko ukuvaleka ziya kwenzeka. Emva koko, phezu koko, kufuneka plasmin peptide ekwaziyo ungasondeli ihlwili nokubuyisela patency wenqanawa.

Okwesithathu, ugrogriso sifo. Ubume kunye nexabiso iiproteni eyenza umzimba, kubaluleke kakhulu. Omzimba, immunoglobulins, interferon - zonke izinto ezibalulekileyo ebalulekileyo emithanjeni kunye nokulwa nezifo. Nayiphi amasuntswana amazwe, molecule ngolunya, iiseli abafileyo okanye inxenye yobume lonke phantsi kuphando ngoko nangoko yi peptide compound. Kungenxa yoko le nto umntu ngumnini, ngaphandle kokusebenzisa amayeza yonke imihla ukuze bazikhusele usuleleko kunye iintsholongwane ezilula.

iipropati ngokomzimba

Ubume bale iiseli weeprothini ngqo kakhulu kwaye kuxhomekeke function. Kodwa iimpawu ebonakalayo peptides ezifanayo kwaye azezi mpawu zilandelayo.

1. iimolekyuli Weight - ukuya 1000000 Daltons.
2. Xa isisombululo zolwelo zenza inkqubo colloidal. Kukho isakhiwo lifumana imali ikwazi iyohluka, ngokuxhomekeke ubumuncu medium.
3. Xa isetyenziswe kwiimeko ezinzima (radiation, asidi okanye kwealkali, ubushushu, njalo njalo) bayakwazi ukuya kwamanye amanqanaba conformations, ngamanye denature. Le nkqubo ngo-90% yamatyala vuhlayiseki. Noko ke, kukho utshintsho reverse - renaturation.

Le propati ezisisiseko iimpawu zomzimba le peptides.