I-enzayim catalase: Iinkalo eziphambili

Catalase - enzyme wafumana eziphilayo phantse bonke bayaphila. Owona msebenzi wayo - ukuba catalyze le yokubola iperoksayidi yehidrojeni zizinto engenabungozi ukuba eziphilayo. Catalase kubaluleke kakhulu ubomi kwiiseli, njengoko khusela kubo, ukuba ndingabatshabalalisi ziintlobo ioksijini lovukelo.

Overview

I-enzayim catalase unxulumene oxidoreductase - class ebanzi enzayim catalyze ukudluliselwa elektroni ukusuka molecule ukunciphisa (donor) ukuya kwemolekyuli oxidant (acceptor).

I-pH ezimpilweni catalase emzimbeni womntu malunga 7 Noko ke, umlinganiselo reaction ayitshintshi kakhulu xa amaxabiso isalathiso hydrogen ukususela 6.8 ukuya 7.5. I-pH ezimpilweni ezinye catalases ezisukela-4 ukuya 11, kuxhomekeka kuhlobo eziphilayo. Iqondo elilelona kwakhona eyahlukileyo ukuba umntu malunga 37 ^° C

Catalase - enye enzymes ngokukhawuleza. molecule enye kuphela iyakwazi ukuguqula izigidi zayo molecule iperoksayidi yehidrojeni amanzi neoksijini ngomzuzwana. Ngokwemiqathango enzymology leyo ethetha ukuba inani elikhulu yeenguqu uphawu enzyme catalase.

isakhiwo enzyme

Catalase i tetramer amatsheyini amane polypeptide, nganye eneyazo ezingaphezu kwama-500 acid ubude. I-enzyme ubunjwe kumaqela amane heme abomvu, yaye apho idityaniswe neentlobo ioksijini esebenzayo. Iqela heme izitho oxidized is a catalase.

History of izovela

Catalase andazekanga izazinzulu iminyaka 1818 de Louis Jacques Thénard usomichiza kufunyanwa iiseli iperoksayidi yehidrojeni esiphila kulo na wacebisa ukuba intshabalalo yayo ngenxa isenzo kukho izinto ongaziwayo eziphilayo.

Ngowe-1900, ekhemesti waseJamani, Apocrypha Leo siqala i "catalase" gama libhekisela into okubolileyo peroxide twisiseka. Wakwazi ukuphendula lo mbuzo, apho i-enzayim catalase eziqulethwe. Ngenxa experimenti ezininzi Apocrypha Leo watyhila ukuba le enzyme uphawu phantse zonke izilwanyana kunye nezityalo. Ezikwiiseli eziphilayo, kwakunye nezinye enzayim ezininzi, catalase uqulathwe peroxisomes.

Ngowe-1937 waba ngowokuqala ukuba nokuntlalutyisa catalase ukusuka yenkomo kwesibindi. KD 250 - ubunzima ngemolekyula ze enzyme wamiselwa ngowe-1938. Ngowe-1981 oosonzululwazi baye bafumana imifanekiso lwesakhiwo-ntathu kwetishu catalase.

Le catalysis hydrogen peroxide

Ngaphandle kokuba iperoksayidi yehidrojeni - imveliso kweenkqubo ezininzi eziqhelekileyo pathways, akukho nto engenabungozi umzimba.

Ukuze kunqandwe ukutshatyalaliswa iiseli zomzimba, iperoksayidi yehidrojeni kufuneka ngokukhawuleza kuguqulelwa kwezinye, yingozi kangako umzimba. Ngulo mngeni ebheka enzyme catalase - ibola le peroxide kwiimolekyuli ezimbini iimolekyuli zamanzi kunye mpilo.

Indlela iperoksayidi yehidrojeni yokubola kwizinto eziphilayo:

2 H ₂ O ₂ → 2 H ₂ O + O ₂

Indlela molekyuli le cleavage enzyme hydrogen peroxide ngu catalase okwangoku ngqo kakuhle. Kucingelwa ukuba indlela kuthatha kuqhubeka ngokwezigaba ezibini - kwinqanaba lokuqala eyenziwe ngentsimbi catalase zokufakelwa iqela yesondo i-atom oksijini peroxide, oku yenza enye molecule yamanzi. In inyathelo lesibini heme oxidized Ngokusebenza kunye nenye molecule ye iperoksayidi yehidrojeni, ngaloo ndlela kusenziwa enye molecule yamanzi kunye omnye molecule ye-oksijini.

Ngesi senzo ke enzyme catalase ngenxa iperoksayidi yehidrojeni, phambi into esebenzayo kwi mbelukazi zeethishu lulula uzimisele. Ukuze oku kongezelela ngokwaneleyo uvavanyo isampula ngemali encinane iperoksayidi yehidrojeni kwaye bagcine indlela. Ubukho enzyme isixelela ukuyilwa maqampu ioksijini. Le ndlela elungileyo kuba ingakufuni naziphi na izixhobo ezizodwa okanye izixhobo - kunokuthi kubonwe ngeliso lenyama.

Kubalulekile ukuphawula ukuba ion nayiphi na heavy metal inokufana inhibitor noncompetitive of catalase. Ngapha koko, wonke benqanda eyaziwa liziphatha inhibitor lokhuphiswano catalase, ukuba ezintweni ezininzi hydrogen peroxide. Arsenates asebenze activators.

isicelo

Action le enzyme catalase abole iperoksayidi yehidrojeni iye yasetyenziswa kwishishini yokutya - usebenzisa le enzyme isusiwe ngobisi H ₂ O ₂ kumalungiselelo sisi. Enye application - nokubopha ukutya ezizodwa ekhusela imveliso igcwala. Catalase lisetyenziswa noshishino lwempahla eyolukiweyo ye zokususwa iperoksayidi yehidrojeni evela amalaphu.

Lusetyenziswa lococeko lenses hi mpimo lowutsongo. Ezinye ntsholongwane iqanjwa iperoksayidi yehidrojeni kunye catalase isetyenziselwa ukwahlula eli candelo phambi kokuba uphinda lenses.

umsebenzi

Umsebenzi we catalase enzyme kuxhomekeke ubudala eziphilayo. Ancedisana abaselula yomsebenzi enzyme iphezulu kakhulu kunaleyo endala. Ngenxa yobudala abantu kunye nezilwanyana umsebenzi catalase ngcembe kunciphisa ngenxa ekugugeni ancedisana amalungu.

Ngokutsho isifundo yakutshanje, ukuncipha umsebenzi catalase yenye oonobangela Ukungaboni iinwele kunokwenzeka. Iperoksayidi yehidrojeni iveliswa ngokuqubekayo kwindlela umzimba womntu, kodwa akukho nto imbi - catalase abole ngokukhawuleza. Kodwa ukuba inqanaba le enzyme lifinyele, kuyacaca ukuba asingabo bonke peroxide hydrogen catalyzed yi enzyme. Ngoko ke, oko discolors ngaphakathi iinwele ezinyibilikayo nedayi zendalo. Le ukufunyanwa engalindelekanga luyavavanywa ngoku ngabaphandi, kwaye idlale indima ekuphuhliseni iziyobisi, asimise Ukungaboni iinwele.