Yintoni umsebenzi kwiproteni enzyme? Le enzymatic umsebenzi iiprotheni: Imizekelo

Umsebenzi yomzimba wethu - yinkqubo entsonkothileyo kakhulu apho izigidi iiseli ababandakanyekayo, amawaka kwezinto ezahlukeneyo. Kodwa kukho enye indawo apho uxhomekeke ngokupheleleyo iiproteni ethile, ngaphandle apho ubomi bomntu okanye isilwanyana bekuya kuba nzima ngokupheleleyo. Njengokuba mhlawumbi thelekelwayo, sithetha ngoku malunga enzymes.

Namhlanje siza kuqwalasela enzymatic umsebenzi iiprothini. Le ndawo enkulu eziphilayo.

Ekubeni isiseko ezi zinto bamhlophe iiproteni, ngoko ke kuqwalaselwa ngawo. Kufuneka wazi ukuba i-enzayim okokuqala esafunyanwa 30 kwenkulungwane ye-19, kuphela izazinzulu wathabatha ngaphezu kwekhulu, ukuze ufikelele inkcazelo engakumbi okanye efanayo ngaphantsi kubo. Ngoko ke yintoni umsebenzi wenziwa enqanda protein? Kule, kwakunye nesakhiwo nezenzo zabo yemizekelo uya kufunda kweli nqaku.

Kufuneka uqonde ukuba asizizo zonke protini kunokuba enzyme, nkqu theory. iiproteni Globular zenza ekwaziyo zibonise umsebenzi ekujonganeni ne intlonipho kwabanye oganikhi khompawundi kuphela. Njengazo zonke ezintweni zemvelo kule klasi, enzayim iqanjwa zeentsalela acid acid. Qaphela ukuba umsebenzi enzymatic kweziyi (imizekelo apho kuya kubakho kweli nqaku) inokwenziwa kuphela enye ubunzima ogama izinyo mncinci kuno 5000.

Yintoni i-enzayimi, le nkcazo yanamhlanje

Enzyme - a yempela zebhayoloji imvelaphi. Kufuneka ubuchule ukuze kukhawuleziswe indlela, ngenxa qha olusondeleleneyo phakathi Kwemithetho Yokwenziwa reactants (substrates). Sinokuthi umsebenzi enzymatic kweziyi - inkqubo ethile catalysis yokusabela kwemichiza ezikhethekileyo ukuba esiphilayo. Kuphela inxalenye encinane kubo olunokuveliswa elebhu.

Kufuneka kuqatshelwe ukuba kule ndawo kuye kukho impumelelo kwiminyaka yakutshanje. Izazinzulu baye nokusondela ekudaleni enzyme ezenziwe enokusetyenziswa nje iinjongo zoqoqosho, kodwa amayeza. Kubhaliwe kuphuhliswa iienzymes enokuthi ngempumelelo ukutshabalalisa nkqu kwiindawo ezincinane zomhlaza incipient.

Zeziphi iindawo enzyme abachaphazeleka ngqo kulo basabela njani?

Qaphela ukuba, wadibana kunye zeendawana aliquki umzimba lonke enzyme, kodwa icandelo elincinane kuphela ekuthiwa kwisiza esebenzayo. Le impahla yabo iphambili complementarity. Le nto ithetha ukuba i-enzayim udalelwe ukuba zeendawana kwi ifomu kunye neempawu zazo ngokwasemzimbeni imichiza. Sinokuthi umsebenzi enqanda kulo mzekelo lumi ngolu hlobo lulandelayo:

• amanzi sihla sivela kumphezulu iqokobhe.
• Kukho deformation ethile (nokwehlukana, umzekelo).
• Emva koko ke zicwangciswe ngendlela ekhethekileyo kwisithuba, ehamba kufutshane omnye komnye.

Ezi zinto kukhokelela yokunyusa indlela. Ngoku, makhe senze uthelekiso phakathi enzyme ehlanganisa ezingaphiliyo.

thelekisa ukusebenza	enzyme	ehlanganisa ezingaphiliyo
Ukukhawuleziswa phambili reverse asabela	okufanayo	okufanayo
Okukodwa (complementarity)	Zivunywa kuphela uhlobo oluthile lwezinto, Okukodwa eliphezulu	Ingaba jikelele, ukhawulezisa ukusabela eziliqela ezifanayo
speed impendulo	Ukwandisa izinga indlela amaxesha kwesigidi ambalwa	Kukukhawuleziswa kwi amakhulu amawaka amaxesha
Ukusabela ukufudumeza	Indlela abasabela iya "hayi" ngenxa nokuguqulwa lilonke okanye olungaphelelanga iiprotheni ababandakanyekayo kulo	Xa itshiswe, uninzi reactions zokuphosa ngokuphindaphindiweyo olukhawulezisiweyo

Njengoko ubona, umsebenzi enzymatic kweziyi kufuna Okukodwa. Ngu ngokwayo iya kongeza ukuba uninzi lwezi iiprothini nazo iintlobo ezithile. Ngamafutshane, enzayim zabantu ngenkankulu efanelekileyo ihagu Guinea.

ulwazi olubalulekileyo malunga isakhiwo enqanda

Isakhiwo ezi zihlanganisi uyazimela nangoko amathathu amanqanaba. Ukuma ephambili bungabonakala kumsi acid iasidi eziyinxalenye enzymes. Ekubeni umsebenzi enzymatic kweziyi, imizekelo apho siye ngokuphindaphindiweyo ezicatshulwe kweli nqaku, ungakwazi kwenziwa kuphela iindidi ezithile iikhompawundi, ukubona kanye ngale ndlela asikho real kakhulu.

Njengoko ukuya kwinqanaba lesibini, kumda isincedisi uzimisele ngendlela yeentlobo ezongezelelweyo neentambo ezingenzeka phakathi kwezi iintsalela acid acid. Le hydrogen unxibelelwano, electrostatic, hydrophobic, kunye Van der unxibelelwano Waals. Ngenxa ukugogeka abanjezelwe loo unxibelelwano kwiindawo ezahlukeneyo enzyme yavelisa α-kweleli, yomtya kunye β-imicu.

Isakhiwo ephakamileyo ngenxa yokuba iinxenye ezinkulu ngokwentelekiso chain polypeptide nemihlambi nje. Izigaba kuphumela ngokuthi domain. Ekugqibeleni, ukwakheka yokugqibela kule sakhiwo kwenzeka kuphela emva kokuba intsebenziswano ezinzileyo phakathi domain ezahlukeneyo. Kufuneka kukhunjulwe ukuba ukuyilwa amathambeka ngokwabo zihamba ngendlela ozimeleyo ngokupheleleyo omnye komnye.

Ezinye iimpawu domain

Ngokuqhelekileyo, chain polypeptide ukuba avele kuwo, iquka nama-150 iintsalela acid acid. Xa domain ziyasebenzisana, kwakheka globule. Ekubeni umsebenzi lwenziwa yi kwiisayithi esebenzayo enzymatic esekelwe phezu kwabo, kufuneka baqonde ukubaluleka kwale nkqubo.

I domain ngokwayo luphawulwa kukuba phakathi kwiintsalela acid acid kubume bayo kukho intsebenziswano ezininzi. Inani labo liphezulu kakhulu ukuba ezo zinto phakathi kwabo domain. Ngoko ke, lo lweHo- phakathi kwabo uthelekisa nezinye "abasemngciphekweni" ukuze izenzo organic izinyibilikisi ezahlukeneyo. Umthamo komyalelo ka 20-30 angstrom cc isngenayo iimolekyuli eziliqela amanzi. domain ezahlukeneyo baqhele ukuba babe isakhiwo eyodwa ngokupheleleyo-ntathu, nto leyo ehambisana kunye nokwenziwa kwemisebenzi ezahlukeneyo ngokupheleleyo.

leendawo ezinale

Njengoko umthetho, iisayithi esebenzayo ibekwe ngokuthe ngqo phakathi domain. Ngako oko, ngasinye kuzo idlala indima ebaluleke kakhulu ekuhambeni basabela njani. Ngenxa eli lungiselelo lwe domains bafumana nezimo okukhulu, ukushukumiseka kwingingqi enzyme. Oku kubaluleke kakhulu, kuba umsebenzi enzymatic lwenziwa kuphela ezo imichiza ukuba ngokufanelekileyo ukutshintsha indawo yayo lomhlaba.

Phakathi ubude polypeptide iqhina kwi umzimba enzyme, kunye nemisebenzi ukuntsonkotha ukuba wenziwe, kukho unxulumano ngqo. zombini indima kama afunyenwe ngokwenza kwisiza esebenzayo basabela njani phakathi domain zokuphosa kwaye ngenxa ukuyilwa domains ezintsha ngokupheleleyo.

Ezinye iiprotheni, enzayim (imizekelo - lysozyme kunye glycogen) ingahluka kakhulu ngobukhulu (129 no 842 iintsalela acid acid, ngokulandelelana), nangona ukusabela catalyzed cleavage neentambo lwemichiza yohlobo olufanayo. Umahluko kukuba enzyme okukhulu ngakumbi kwaye ezinkulu bayakwazi ukulawula ngcono isikhundla salo space, eqinisekisa uzinzo kunye mkhulu nesantya yokusabela.

Eyona engundoqo yokuhlela enqanda

wavuma ngoku bandile ehlabathini luhlelo eqhelekileyo. Ngokutsho kwakhe, sime iiklasi ezintandathu ezingundoqo, kunye subclasses efanelekileyo. Sicinga kuphela engundoqo. Nazi ke:

1. Oxidoreductases. Umsebenzi enqanda kulo mzekelo - inkanuko ngayo redox.

2. Transferases. Ukuze ndisimise substrates transfer phakathi kwamaqela zilandelayo:

• iiyunithi carbon-nye.
• Egqithiseleyo aldehydes kunye ketones.
• amacandelo Acyl kunye glycosyl.
• Alkyl (njenge ngaphandle lingenako ukuthwala CH3) iintsalela.
• iziseko nitrogen.
• Groups equlethe phosphorus.

3. Hydrolases. Kulo mzekelo, umsebenzi enzymatic kukuba ukuyinamathelisa iiproteni ntlobo zilandelayo iikhompawundi:

• Esters.
• Glycosides.
• Esters, kunye thioesters.
• uhlobo Peptide izitropu.
• uhlobo Relationship CN (ngaphandle kwe peptide efanayo).

4. Lyases. Ngaba uyakwazi disengaging amaqela kunye kumiswa esilandelayo ibhondi kabini. Ngaphezu koko, akukho ndisimise inkqubo ngokubaxwa: ukudibanisa amaqela akhethiweyo ukuze kabini izitropu.

5. Isomerases. Kulo mzekelo, umsebenzi enzymatic kweziyi intsonkothile reactions catalysis isomeric. Eli qela ibandakanya enzyme zilandelayo:

• Racemase, epimerase.
• Tsistransizomerazy.
• oxidoreductases Intramolecular.
• transferases Intramolecular.
• lyase Intramolecular.

6. Ligases (eyaziwa ngokuba synthetase). zisetyenziselwa ukuqhekeka ATP ngoxa zokubumba imidibaniso ezithile.

Kulula ukuba uqaphele ukuba umsebenzi enzymatic kweziyi kubalulekile kakhulu, njengoko kwezinye ulawulo ubukhulu phantse zonke abasabela ukuthatha kwindawo yesibini zonke emzimbeni wakho.

Okuseleyo enzyme emva intsebenziswano kunye zeendawana?

Ngokufuthi, le enzyme iproteni imvelaphi globular, iziko asebenzayo apho limelwe iintsalela yayo efanayo acid acid. Kuzo zonke ezinye iimeko, xa inxalenye iziko enxulumene ngokuqinileyo kuyo iqela zokufakelwa okanye coenzyme (ATP, umzekelo), ubudlelwane ithambile kakhulu. A yoguquko wabiza holoenzyme, nento yayo, emva kususwa ATP apoenzyme kwakhiwa.

Ngaloo ndlela, ngokwale phawu enzayim ihlelwa maqela alandelayo:

• hydrolase Simple, lyase, kunye isomerase, leyo ngokubanzi azinamgaqo isiseko coenzyme.
• iiproteni enzyme (imizekelo - ezinye transaminase) eliquka iqela zokufakelwa (lipoic acid, umzekelo). Eli qela libandakanya ezininzi peroxidase.
• Enizmy apho coenzyme ngokutsha efunekayo. Ezi ziquka kinases, kwakunye uninzi oxidoreductases.
• Ezinye ehlanganisa, ukwakhiwa kweengongoma ezahlukileyo ze apho akukaqondwa kakuhle.

Zonke izinto eziyinxalenye iqela lokuqala, ezisetyenziswa kakhulu yokudla. Zonke ezinye ehlanganisa zifuna iimeko ezithile kakhulu ukuba kusebenze layo, ngoko ukusebenza emzimbeni kuphela, okanye kwezinye experiments elebhu. Ngenxa yoko, umsebenzi enzymatic - oku yokusabela ngqo kakhulu, nto leyo equka eyakhayo (catalysis) abasabela kwiintlobo ezithile iimeko kakuhle echazwe lomzimba womntu, okanye isilwanyana.

Kwenzeka ntoni kule ndawo esebenzayo, okanye kutheni enzayim asebenza ngempumelelo?

Besesitshilo ngokuphindaphindiweyo ukuba isitshixo ukuqondwa catalysis enzymatic kukudala iziko esebenzayo. Kukho ukuba esibophelelayo ezizodwa zeendawana, leyo kwiimeko ezinjalo esebenzayo kakhulu kusabela. Ukuze uqonde ukuntsonkotha abasabela kuthwalelwa apho phandle, ukunika umzekelo elula ukuba yenzeke Ukubila iswekile, kuyimfuneko kanye enqanda 12! Ngokulinganayo intsebenziswano enzima kwenzeka kuphela ngenxa yokuba iproteni ezisebenza umsebenzi enzymatic unalo iqondo eliphezulu Okukodwa.

Iintlobo enqanda Okukodwa

Kuyinto efanele. Kulo mzekelo, ingakumbi iboniswa omnye kuphela, echazwe ngokungqongqo uhlobo enzyme. Ngenxa yoko, urease isebenzisana kuphela urea. Ubisi lactose njengoko ungena indlela phantsi kwazo naziphi na iimeko. Yiloo nto umsebenzi wenziwa iiproteni, enzyme emzimbeni.

Ukongeza, iqela ayikho Okukodwa ingaqhelekanga epheleleyo. Njengoko eziqondwa igama, kule meko kukho "receptivity" ngokungqongqo udidi iikhompawundi eziphilayo (esters, kubandakanywa alkoholi ezintsonkothileyo okanye aldehydes). Umzekelo, pepsin, leyo yenye enzayim eziphambili esiswini, ibonisa kuphela Okukodwa ngenxa haydrolisis iibhondi peptide. dehydrogenase Utywala isebenzisana kuphela alkoholi kunye laktikodegidraza gqiphu nantoni na ngaphandle asidi Alpha-hydroxy.

Kwakhona kuyenzeka ukuba umsebenzi enzymatic uphawu iqela elithile iikhompawundi, kodwa phantsi kweemeko ezithile, i-enzayim isinyathelo eyahlukileyo kakhulu ukusuka 'injongo' zazo eziphambili into. Kulo mzekelo, lo kuvala "owalusa" kudidi ezithile izinto, kodwa phantsi kweemeko ezithile ngayo ninamathele kunye nezinye kusitsha (hayi ukuba okulingana). Noko ke, kule imeko, basabela iza kuhamba kakhulu ngokucothayo.

Luphawu eyaziwa ngokuba ukukwazi trypsin ukwenza iibhondi peptide, kodwa bambalwa abantu bazi ukuba le protein ezisebenza umsebenzi enzyme kwisiqwenga zesisu, ukuze kulunge zisenokuxabana iikhompawundi Ester ezahlukeneyo.

Okokugqibela, kukho ingakumbi woqondo. Ezi enzyme angasebenzisana iintlobo ngeentlobo izinto uluhlu ngokupheleleyo, kodwa kuphela phantsi komqathango wokuba babe iipropati woqondo kakuhle echazwe. Ngoko ke, lo msebenzi enzymatic kweziyi kule meko ifana kakhulu kumgaqo yesenzo enzyme, ehlanganisa kunye nemvelaphi nezingaphiliyo.

Ziziphi izinto ukuqinisekisa ukusebenza catalysis?

Namhlanje, kukholelwa ukuba izinto ezibonakalisa ngomlinganiselo omkhulu kakhulu ukuba ucikizeko lwezi enzyme:

• kugxila ukusebenza.
• effect orientation lomhlaba.
• Ngazibini iziko reaction esebenzayo.

Ngokubanzi, isiphumo ukuzikisa ingqondo kweziyobisi ayahlukanga ukusuka ukuba abasabela catalysis ezingaphiliyo. Kulo mzekelo, iqela zeendawana enjalo, nto leyo amaxesha amaninzi mkhulu ixabiso efanayo zonke ezinye izinto umthamo isisombululo elisembindini esebenzayo. Xa iziko reaction ukuhlela emane izinto molecule ekufuneka zisenokuxabana nezinye. Asinto nzima ukuba baqashele ukuba oku kukhokelela ekwandeni indlela izinga zemichiza imiyalelo ezininzi ubukhulu.

Xa inkqubo yemichiza eqhelekileyo ithatha indawo, kubalulekile kakhulu, nto leyo eyinxalenye molekyuli lokunxibelelana zingqubane kunye nabanye. Ngamafutshane, iyeza kwemolekyuli ngexesha le ngozi, kufuneka ngokungqongqo ezijolise xa kuthelekiswa namanye. Ngenxa yokuba into ngokunyanzelwa, koko zicwangciswe onke amacandelo inxaxheba kumgca ethile, basabela catalysis kwandiswa ezintathu nemiyalelo ithuba enjalo kwisiza esebenzayo ye-enzyme.

Phantsi multifunctionality kule meko libhekisela ipropati onke amacandelo kwisiza esebenzayo ngexesha elifanayo (okanye ngqongqo ezinxityelelanisiweyo) isenzo kwi molecule "iphathwa" kweziyobisi. Enanikade omnye (molecule) akukho kuphela ngokufanelekileyo fixed emajukujukwini (bona. Ngaphezu), kodwa Itshintsha kakhulu iimpawu zayo. Konke oku kunye kukhokelela kukuba i-enzyme ibizwa ngokuba kulula kakhulu ukuba asebenze kwi zeendawana njengoko kuyimfuneko.