Enzyme ngamachiza ezinto eziphilayo. Isakhiwo, izakhiwo kunye nemisebenzi

Iseli zonke eziphilayo, izigidi ekudibaneni kwemichiza uthathe indawo. Ngamnye kubo kubalulekile, ngoko kubalulekile ukugcina isantya iinkqubo zebhayoloji kwinqanaba eliphezulu. Phantse wonke ukusabela catalyzed yi enzyme yayo. Yintoni enzyme? Yintoni indima yazo ehokweni?

Enzyme. definition

Igama elithi "enzayimi" livela kwisiLatini fermentum - igwele. Kwakhona kubizwa ngokuba enzayim evela Greek en zyme - "ephala."

Enzyme - izinto eziphilayo esebenzayo, ngoko nayiphi na impendulo esivulekayo esiseleni, Asinakuyenza ngaphandle kwabo. Ezi zinto benza zokuthundeza. Ngako oko, naliphi enzyme na iimpawu ezimbini eziphambili:

1) Enzyme ibalekisa indlela kwemichiza, kodwa lingapheli.

2) Ixabiso le-njalo lizama ayitshintshi, kodwa ibalekisa kuphela impumelelo eli xabiso.

Enzyme kukhawulezisa reactions kwemichiza kumawaka, kwaye kwezinye iimeko, amaxesha yesigidi. Oku kuthetha ukuba ukungabikho kwenkqubo enzyme zonke iinkqubo intracellular sele ndayeka, kwaye iseli ngokwalo uyafa. Ngoko ke, indima enqanda njengoko izithako ezisebenzayo iphezulu.

Iintlobo enqanda kwenza kube lula ukuba diversify ukulawula iseli ukutya. Kuyo nayiphi na kubangela reactions abathatha inxaxheba kwiiklasi ezininzi ezahlukeneyo enqanda. ehlanganisa zebhayoloji abe selectivity ophezulu ngokusebenzisa Ukumila ethile kwemolekyuli. T. To. Kwiimeko ezininzi enzyme iiprothini ngemvelo, ukuba kubume ephakamileyo okanye koqeqesho. Isizathu kukuba kwakhona ingakumbi kwemolekyuli.

Umsebenzi enqanda kwiseli

Eyona Umsebenzi enzyme - lunikezelo engqinelanayo indlela. Nazo naziphi na iinkqubo ukuxubana, ukususela yokubola iperoksayidi yehidrojeni kunye glycolysis nesiphelo, ufuna phambi kuvala eziphilayo.

ukusebenza eyiyo enqanda kufikelelwe Okukodwa eliphezulu ukuya zeendawana ethile. Oku kuthetha ukuba iza sakubanako ukunyusa isantya kuphela indlela ethile kwaye kungekho ngaphezulu, nokuba efana kakhulu. Ngu iqondo ingakumbi enzyme, la maqela alandelayo:

1) enqanda kunye Okukodwa ingundoqo xa catalyzed enye kuphela indlela enye. Umzekelo, collagenase digests lo collagen, kwaye maltase lusicande maltose.

2) enqanda kunye Okukodwa isalamane. Oku kuquka izinto ezinokuthi catalyze kwiklasi ezithile reactions, umzekelo, cleavage hydrolytic.

umsebenzi biocatalyst luqala uxhulumaniso lwe kwisiza esebenzayo ukuya zeendawana. Ngelo xesha vulavula hi intsebenziswano edibanayo efanayo kwilokhu isitshixo. Oku kubhekisela umdlalo ngokupheleleyo kunye zeendawana yakha iziko esebenzayo, nto leyo eyenza kube lula ukuba ukukhawulezisa indlela.

Inyathelo elilandelayo sikuko ekuhambeni basabela njani. ukhula zawo isantya yintshukumo zakhiwo enzyme. Ekugqibeleni, sifumana i-enzayim, nto leyo ehambisana kunye neemveliso basabela.

Isigaba sokugqibela - ukususa iimveliso usabela enzyme, emva koko isiza esebenzayo kwakhona azive ekhululekile ukuba omnye umsebenzi.

Ngokwalo, umsebenzi enzyme kwinqanaba ngalinye angabhalwa ngolu hlobo:

1) S + E -> SE

2) SE -> SP

3) SP -> S + P, apho S - na zeendawana, E - i-enzayim, kunye P - imveliso.

ngezigaba enqanda

Emzimbeni womntu, unako ukufumana inani elikhulu enqanda. Lonke ulwazi malunga nemisebenzi yabo emsebenzini systematized, kwaye ngenxa yoko kukho kudidi eqhelekileyo, apho unako lula ukubona ukuba yintoni na kuvala ethile. Nazi iiklasi ezintandathu ezisisiseko enqanda, kwakunye eminye imizekelo nomnye.

1. Oxidoreductase.

Enzyme kule klasi catalyze ngayo redox. Total waphinda sub-amaqela 17. Oxidoreductases zidla non-protein isahlulo ezinikiweyo vitamin okanye heme.

Phakathi oxidoreductases zidla wafumana subgroups zilandelayo:

a) Dehydrogenase. Eziphilayo-dehydrogenase enzyme ohlaba athom yeehidrojeni abatshintshela kuyo kwenye zeendawana. Le kwama ixhaphake kakhulu abasabela ngayo nokuphefumla, photosynthesis. Njengenxalenye dehydrogenase ethile khona ngohlobo coenzyme nad / NADH okanye flavoproteins asingomkhwa / FMN. Kudla kukho ion yesinyithi. Imizekelo iquka enzyme ezifana tsitohromreduktazy, dehydrogenase pyruvate, dehydrogenase isocitrate, kwaye kananjalo enzayim ezininzi isibindi (zincancise dehydrogenase, glutamate dehydrogenase, njalo njalo. D.).

b) oxidases. A Inani enqanda catalyze kongezwe oxygen hydrogen, apho iimveliso indlela ingaba amanzi okanye iperoksayidi yehidrojeni (H ₂ 0, H ₂ 0 _2). Imizekelo ye-enzayim cytochrome oxidase, tyrosinase.

c) peroxidase kunye catalase - enzayim catalyze le yokubola H _{2 O-2} ukuya emanzini neoksijini.

g) oxygenase. Ezi biocatalysts ukukhawulezisa ioksijini uncamathiselo kwi zeendawana. Dofamingidroksilaza - omnye weyona mizekelo enqanda ezinjalo.

2. Transferases.

Okucetyiweyo enzyme eli qela ukudluliselwa radicals ukusuka ubuncwane lowo wayingcwalisayo uthe kweziyobisi kumamkeli.

a) methyltransferase. DNA methyltransferase - enzayim angundoqo ukulawula inkqubo ye DNA ukuphindaphindeka. nucleotides kwesipirithi idlala indima enkulu ekumiseleni umsebenzi asidi acid.

b) acyltransferase. Enzyme yale iqelana bathuthwayo ukusuka molecule elinye ukuya kwelinye iqela acyl. Imizekelo acyltransferases: lecithin-cholesterol acyltransferase (ephethe iqela ezisebenzayo kunye acid okunamafutha kwi cholesterol), lizofosfatidilholinatsiltransferaza (iqela acyl idluliselwa lysophosphatidylcholine).

c) aminotransferases - enzayim abandakanyeka ukuguquka asidi acid. Imizekelo ye-enzayim aminotransferase alanine leyo catalyzes ukuba Yindibanisela alanine ukusuka pyruvate kunye glutamate ngokuthi kudluliselwe iqela acid.

g) phosphotransferase. Enzyme catalyze kongezwe le nkqutyana qela iqela phosphate. Elinye igama phosphotransferase kinase, kuxhaphake kakhulu. Imizekelo iquka enzyme ezifana hexokinase kunye aspartate, leyo ziqhotyoshelwe kumsi hexose phosphate (ikakhulu glucose), kunye aspartic acid , ngokulandelelana.

3. Hydrolases - udidi enzayim catalyze i cleavage neentambo kwi molecule, kulandele ukongeza yamanzi. Izinto ebe zizezakho kweli qela - i-enzayim main yokwetyisa.

a) esterases - ukwaphula imixokelelwane Ester. Umzekelo - lipases ukuba ndoyidiliza amafutha.

b) glycosidases. Eziphilayo enzyme yale ngcelele kuxhomekeke ekutshatyalalisweni imixokelelwane glycoside of Iipholima (oligosaccharides kunye polysaccharides). Imizekelo: amylase, sucrase, maltase.

c) peptidase - enzayim catalyze ukuwa iiprothini ukuba acid asidi. enzyme ezinxulumene-Peptidase ezifana pepsin, trypsin, chymotrypsin, karboiksipeptidaza.

g) Amidases - imixokelelwane ninamathele amide. Imizekelo: .. Arginase, urease, glutaminase njl abaninzi amidase enqanda zifumaneka kumjikelo ornithine.

4. Lyases - enzayim kwimisebenzi efana hydrolases, nangona kunjalo kwi cleavage neentambo kwi iimolekyuli liphele amanzi. Enzyme kule klasi kusoloko ube yinxalenye yale non-protein isahlulo, umzekelo, ngokohlobo iivithamini B1 kunye B6.

a) decarboxylase. Ezi enzyme sithathele C-C bond. Imizekelo glutamic acid decarboxylase okanye decarboxylase pyruvate.

b) hydratase kunye dehydratase - enzayim catalyze i cleavage ka C-O izitropu.

c) I-amidine-lyases - yokonakalisa C-N bond. Umzekelo: argininsuktsinatliaza.

g) R-O lyase. enzyme ezinjalo bakholisa lwanamathela iqela phosphate evela izinto zeendawana. UMZEKELO: cyclase adenylyl.

Eziphilayo enqanda ngokusekelwe kwisakhiwo sabo

Ukukwazi enzyme ngalinye kumiselwa ngamnye, nesakhiwo sayo okusegazini kuphela. Nawuphi enzyme - ngokuyintloko protein, nesakhiwo sayo kunye nezinga ukusonga kudlala indima ebaluleke kakhulu ekumiseleni umsebenzi wayo.

biocatalyst nganye luphawulwa ebusweni iziko esebenzayo, mvisiswano leyo, kwelinye icala, yahlulelwe kwii ariya ezininzi enomahluko nabasebenzayo:

1) encedisa ukuqalisa Centre - ummandla eyodwa kwiproteni, apho yokubambelela enzyme ukuya zeendawana. Kuxhomekeka Ukumila kwe kwiproteni iziko molecule zokuphosa unokuthabatha ezahlukahlukeneyo, nto leyo kufuneka ne zeendawana kwakunye kwilokhu isitshixo. Loo isakhiwo esimbaxa ichaza isizathu neprothini enzyme kwi karhulumente emfundo ephakamileyo okanye koqeqesho.

2) Adsorption Centre - lisebenza njenge "umnikazi". Apha, okokuqala zonke nxibelelwano luqhubekayo phakathi kwemolekyuli enzyme kunye molecule zeendawana. Nangona kunjalo, lo uxhumo yakha iziko adsorption, buthathaka kakhulu, yaye basabela zokuphosa na ingathityazwa kweli nqanaba.

3) Amaziko Allosteric inokufunyanwa kwiziko esebenzayo, nakuyo yonke kumphezulu enzyme. umsebenzi wazo - ukulawulwa enzyme. UMmiselo lwenzeka nge iimolekyuli inhibitors kunye activators iimolekyuli.

Iiproteni isilumeki ngokuzibophelela kwi kwemolekyuli enzyme, ukukhawulezisa ukusebenza kwawo. Inhibitors, phezu koko, zinqanda umsebenzi zokuphosa, kwaye oku kungenzeka ngeendlela ezimbini: nokuba molecule enebana kummandla kwiziko allosteric kweziko ebonakalayo enzyme (inhibition kukhuphiswano) okanye iqhotyoshelwe omnye kummandla protini (inhibition noncompetitive). inhibition uKhuphiswano kugqalwa ngempumelelo ngakumbi. Emva isithuba ngaloo esivalekileyo zeendawana ngokuzibophelela kwi-enzayim, yaye le nkqubo kunokwenzeka kuphela xa kuqondana phantse ngokupheleleyo kwemolekyuli inhibitor kwaye zenze liziko esebenzayo.

Enzyme kaninzi akunalo asidi acid, kodwa ezinye izinto eziphilayo nezingaphiliyo. Ngako oko, apoenzyme ekwanti - proteinaceous inxenye coenzyme - moiety organic kunye cofactor - inxalenye ezingaphiliyo. Coenzyme angamelwa ulgevodami, amafutha, ii-asidi acid, iivithamini. Ngenxa yoko, i-co-factor - basoloko exhasayo ion yesinyithi. umsebenzi enzyme uzimisele nasekumeni yayo: izinto ezongezelelweyo eziyakubandakanywa kwi-ekwakhiweni, atshintshe iipropati encedisa ukuqalisa imisebenzi. iintlobo ezahlukeneyo enqanda - sisiphumo ngokudibanisa zonke ezi zinto zenze isakhiwo.

Regulation umsebenzi enqanda

Enqanda nomongo eziphilayo esebenzayo akusoloko kuyimfuneko ukuba umzimba. Eziphilayo enqanda kukuba babe kwimeko iiseli abahlala ngokugqithiseleyo catalysis ingozi. Ukuthintela iziphumo eziyingozi emzimbeni enzyme kuyimfuneko ukulawula ngandlel umsebenzi wabo.

T. To. Enzyme iiprothini kwindalo, ukuba sele kutshatyalaliswa kwiqondo lobushushu eliphezulu. inkqubo nokuguqulwa na ingathityazwa, kodwa ezinokuchaphazela kakhulu iziyobisi.

Kwakhona pH idlala indima ebalulekileyo ummiselo. umsebenzi transcriptase obukhulu jikelele ambona pH (7,0-7,2). Kwakhona iye enzayim ukusebenza kuphela phantsi kweemeko emuncu okanye kuphela obrak. Ngoko, kwi lysosomes cellular zigcinwe pH ephantsi, apho umsebenzi ezinintsi enqanda hydrolytic. Xa kuthe qha ngengozi kunye icytoplasm, apho bume ikufutshane cala, umsebenzi wabo luza kuncipha. ukhuseleko enjalo ukusuka 'samopoedaniya "isekelwe phezu iimpawu hydrolase.

Kufanelekile ukuba sikhankanye ngokubaluleka coenzyme kunye cofactor kuhlanganiselo enqanda. Ukubakho iivithamini okanye ion yesinyithi kakhulu kuchaphazela ukusebenza ezinye enzyme ezithile.

Nokuhlelwa enqanda

Zonke enzyme yomzimba ababizwe obuphezu kwabo nayiphi na iiklasi, kwakunye zeendawana ngazo kusabela. Ngamanye amaxesha le nokuhlelwa ngendlela esetyenziswa akukho namnye kodwa ezimbini zeendawana kwi kwisihloko.

Imizekelo amagama kwezinye enzyme:

1. Isibindi enzyme: zincancise degidrogen aza-glutamate-aza-degidrogen.
2. Elipheleleyo Igama yenkqubo enzyme: zincancise + nad-aza -oksidoredukt.

amagama alondolozwe kwaye ezingenamsebenzi, ezo musa bathobele imithetho nokuhlelwa. Imizekelo enzyme: trypsin, chymotrypsin, pepsin.

Inkqubo yokuqaphela enqanda

Imisebenzi enqanda azimisele nokuba kwinqanaba yemfuza. Ekubeni molecule ngokubanzi -. NgeeProteni, kwaye kuyondelelaniswe wayo ncam iinkqubo umbhalo kanye translation.

enzyme yolungelelwaniso kwenzeka ngolu hlobo lulandelayo. Ekuqaleni, DNA ukufunda ulwazi malunga enzyme efunekayo ukwenza mRNA. Messenger RNA buqonda zonke acid eziyinxalenye enzyme. UmMiselo enqanda kwakhona zenzeke kwinqanaba DNA, ukuba imveliso basabela catalyzed ngokwaneleyo zokumisa gene umbhalo kanye phezu koko, ukuba kukho imfuneko kwimveliso, usebenze inkqubo tumbuluxiwa.

Xa mRNA yakhululwa kuloo kukho icytoplasm, isigaba esilandelayo - losasazo. On ribosomes reticulum endoplasmic kuhlanganiswa chain ephambili eyenziwa acid edityaniswe ngeentambo peptide. Noko ke, kwemolekyuli iiprothini isakhiwo zaseprayimari ungakwazi ukwenza umsebenzi walo enzymatic.

Umsebenzi enzyme ixhomekeke izakhiwo protein. EPS efanayo iproteni kwenzeka linegunya, ngaloo ndlela ezakha isakhiwo yokuqala lesibini uze emfundo ephakamileyo. Le Yindibanisela kwezinye enzayim iyakuvingca kweli nqanaba, kodwa ukuphucula umsebenzi kukukhokela rhoqo kuyimfuneko sokuthimba kunye cofactor coenzyme.

iswekile, nucleic, amafutha kunye neevithamini: Kwiindawo ezithile reticulum endoplasmic oza amacandelo somgquba enzyme eqhotyoshelweyo. Ezinye enzyme ayikwazi ukusebenza ngaphandle ebusweni coenzyme.

Cofactor idlala indima ebalulekileyo ukuyilwa kobume koqeqesho le protini. Eminye imisebenzi enqanda zifumaneka kuphela xa umbutho domain protein. Ngoko ke kubaluleke kakhulu kwisakhiwo sabo phambi koqeqesho kanye apho unxibelelwano yokungena phakathi globules ezininzi iproteni i ion yesinyithi.

iintlobo ezininzi enqanda

Kukho iimeko apho kuyimfuneko phambi enqanda emininzi catalyze ukusabela okufanayo, kodwa kwahluka enye kwenye kwezinye iinkalo. Umzekelo, i-enzayim unako ukusebenza degrees-20, kodwa 0 degrees, akayi kuba nako ukwenza imisebenzi yayo. Kufuneka wenze ntoni kwimeko enjalo, umzimba ephilileyo kwiqondo lobushushu eliphantsi?

Le ngxaki ngokulula isonjululwe bubukho enqanda emininzi catalyze ukusabela okufanayo, kodwa iimeko zomsebenzi ezahlukeneyo. Kukho iindidi ezimbini iintlobo ezininzi enqanda:

1. Isoenzymes. iiproteni ezinjalo beminwe yemfuza ezahlukeneyo, baza benziwa asidi ezahlukeneyo acid, kodwa catalyze ukusabela okufanayo.
2. Iifom True ezininzi. Ezi proteni amagama ukusuka gene efanayo, kodwa kwenzeka kwi peptides ribosomes ukulungiswa. Xa imveliso wavelisa iintlobo ezininzi enzyme efanayo.

Ngenxa yoko, ngeendlela ezininzi lohlobo yokuqala siya kwenziwa kwinqanaba yemfuza, xa yesibini - on the post-translational.

enzyme meaning

Ukusetyenziswa enzyme amayeza eza phantsi umba amayeza amatsha, njengenxalenye apho izinto sele ubuninzi ekunene. Izazinzulu ziye engekalifumani indlela ukuvuselela Yindibanisela ezingekhoyo enzyme emzimbeni, kodwa ngoku isasazwa ngokubanzi iziyobisi zilibuyise ixesha osingelo-yabo.

enzyme ezahlukeneyo iseli catalyze inani elikhulu reactions enxulumene nokugcinwa yobomi. Enye yezi abameli enizmov nucleases iqela: endonuclease kunye exonuclease. Umsebenzi wabo kukugcina kwinqanaba rhoqo nucleic kwisisele, ukususwa DNA onakeleyo RNA.

Musa ukulibala malunga ngxaki yokusetyenziswa igazi ekunqandeni. Njengenyathelo olusebenzayo wokhuseleko, inkqubo lilawulwa linani enqanda. OyiNtloko phakathi kwabo thrombin, oguqula engasebenziyo protein lwefibrinogen ibe fibrin esebenzayo. ngentambo yayo kudala uhlobo lomsebenzi womnatha occludes isiza ukwenzakala inqanawa, nto leyo ethi ithintele ilahleko igazi ngokugqithiseleyo.

Enzyme zisetyenziswa iwayini, iyasondela kulo, ukuveliswa iimveliso zobisi ezininzi. Kuba utywala ukusuka igwele iswekile ingasetyenziswa, ke, kuba isenzeko ngempumelelo kwale nkqubo ukucatshulwa ngokwaneleyo kubo.

iinyani ezinika umdla malunga apho babengazi ukuba

- Yonke enqanda umzimba bakaThixo ubunzima elikhulu - 5,000 ukuya 1.000.000 Da. Oku kungenxa kubukho iiprothini molecule. Thelekisa ubunzima beemolekyuli glucose - 180 Ewe, kunye ne-carbon dioxide - iyonke ngama-44 Ewe.

- Ukuza kuthi ga ngoku, wavula enzayim ngaphezu kwama-2000 abafunyanwa kwiiseli eziphilayo ezahlukeneyo. Noko ke, inkoliso yezi zinto nangoku kufundwe ngokupheleleyo.

- umsebenzi Enzyme isetyenziswa ukuze bafumane emigutyeni zokuhlamba olusebenzayo. Apha, enzyme ukufeza indima efanayo emzimbeni; bagqobhozile phantsi izinto eziphilayo, yaye lo mhlaba inceda yokulwa amabala. Kucetyiswa ukuba basebenzise i isepha enjalo kubushushu ongekho ngaphezulu kwe degrees 50, kungenjalo ukuze kwinkqubo nokuguqulwa.

- Ngokwe-manani,-20% yabantu ehlabathini lonke ubunzima ngenxa yokungabikho nayiphi na enzymes.

- Malunga iimpawu enqanda eyaziwa ixesha elide, kodwa kuphela ngo-1897, abantu baqonda ukuba igwele, ibe sisicatshulwa kwiiseli zabo zingasetyenziswa igwele iswekile ibe utywala.