A enzyme catalase: babban fasali

Catalase - wani enzyme samu a kusan duk rayayyun kwayoyin halitta. Its main aiki - don tsara cikin bazuwar na hydrogen peroxide cikin m abubuwa ga kwayoyin. Catalase ne na bayar da muhimmanci ga rayuwar da Kwayoyin, kamar yadda ya kare su daga hallaka ta amsawa oxygen jinsi.

Overview

A enzyme catalase da dangantaka da oxidoreductase - m aji na enzymes cewa tsara da canja wurin da electrons daga rage kwayoyin (bayarwa) zuwa ga oxidant kwayoyin (Mai karɓar).

A ganiya aiki PH ga catalase a jikin mutum shi ne game da 7, duk da haka, da dauki kudi ba ya canja muhimmanci a dabi'u na hydrogen index of daga 6.8 zuwa 7.5. A PH ganiya ga sauran catalases jere daga 4 zuwa 11, dangane da irin kwayoyin. A ganiya zafin jiki ne ma daban-daban ga wani mutum da aka game da 37 ^° C

Catalase - daya daga cikin gaggawa enzymes. Daya kawai kwayoyin da yake iya mayar da miliyoyin kwayoyin na hydrogen peroxide zuwa ruwa da oxygen da na biyu. A cikin sharuddan enzymology wanda ke nufin cewa babban adadin juyin halayyar da enzyme catalase.

Structure enzyme

Catalase ne tetramer na hudu polypeptide sarƙoƙi, kowanne daga abin yana da fiye da amino acid 500 a tsawon. A enzyme da aka hada da hudu kungiyoyin na heme porphyry, kuma ta hanyar da reacts tare da aiki oxygen jinsi. A oxidized heme} afar roba kungiyar ne a catalase.

Tarihi na samu

Catalase aka ba su sani ba masana kimiyya 1818 shekaru har Louis Jacques Thénard sunadarai gano a cikin rayayyun tantani na hydrogen peroxide ba da shawarar cewa ta hallaka saboda da mataki na wani unknown nazarin halittu abu.

A shekarar 1900, wani Jamus sunadarai, Oskar Leo farko da ya gabatar da "catalase" kalma koma zuwa wani m abu saki peroxide. Ya ya iya amsa tambayar, inda enzyme catalase dauke. A sakamakon yawa gwajen Oskar Leo bayyana cewa wannan enzyme ne halayyar kusan dukan dabbobi da kuma shuke-shuke. A rayayyun tantani, kazalika da yawa wasu enzymes, catalase yana kunshe ne a cikin peroxisomes.

A 1937 ya kasance na farko da ya crystallize catalase daga naman sa hanta. 250 KD - kwayoyin nauyi na enzyme da aka ƙaddara a 1938. A shekarar 1981 masana kimiyya sun samu images of uku-girma tsarin Bovine catalase.

A catalysis na hydrogen peroxide

Duk da cewa hydrogen peroxide - wani samfurin na da yawa al'ada tafiyar matakai na rayuwa, shi ne ba m ga jiki.

Don hana halakar Kwayoyin kuma tsokoki, hydrogen peroxide dole ne sauri tuba zuwa sauran, kasa kawo hadari ga jiki. Shi ne wannan kalubale da kuma copes enzyme catalase - shi decomposes da peroxide zuwa biyu kwayoyin na ruwa kwayoyin da oxygen kwayoyin.

A dauki na hydrogen peroxide bazuwar a zaune kyallen takarda:

2 H ₂ Ya ₂ → 2 H ₂ Ya + O ₂

A kwayoyin inji na tsakiyan nonon enzyme na hydrogen peroxide da catalase ba tukuna daidai gane. An zaci cewa da dauki faruwa a matakai biyu - na farko da mataki kunsha na baƙin ƙarfe catalase} afar roba kungiyar bonded zuwa wani oxygen zarra na peroxide, wannan ya haifar da daya kwayoyin na ruwa. A karo na biyu mataki da oxidized heme hulda da wani sunadarin na hydrogen peroxide, game da shi, ya kafa wani sunadarin na ruwa da kuma daya kwayoyin na oxygen.

Ta hanyar wannan mataki na enzyme catalase ga hydrogen peroxide, da gaban da aiki dũkiyõyinsu a cikin nama samfurori da aka sauƙi m. Don wannan ƙara isa ga gwajin samfurin karamin adadin hydrogen peroxide da kuma tsayar da dauki. A gaban da enzyme gaya wa samuwar oxygen kumfa. Wannan dauki kyau domin shi ba ya bukatar wani na musamman kayayyakin aiki, ko kayan aiki - ana iya gani da ido tsirara.

Shi ne ya kamata a lura da cewa an ion na wani nauyi karfe iya aiki a matsayin mai noncompetitive hanawa na catalase. Bugu da ƙari kuma, duk aka sani cyanide behaves kamar yadda wani m hanawa na catalase, idan a cikin da yawa tsokoki na hydrogen peroxide. Arsenates yi aiki a matsayin activators.

aikace-aikace

Action na enzyme catalase decomposes hydrogen peroxide da aka yi amfani da masana'antun sarrafa kayayyakin abinci - yin amfani da wannan enzyme an cire daga madara H ₂ Ya ₂ ga shiri na cuku. Wani aikace-aikace - musamman abinci marufi da kare da samfurin da hadawan abu da iskar shaka. Catalase aka kuma yi amfani da yadi masana'antu domin kau da hydrogen peroxide daga yadudduka.

Ta amfani da kiwon lafiya na lamba ruwan tabarau a kananan yawa. Wasu disinfectants an hada da hydrogen peroxide da kuma catalase ake amfani da su raba wannan bangaren da reusing ruwan tabarau.

aiki

Aiki na catalase enzyme dogara da shekaru da kwayoyin. The matasa kyallen takarda da enzyme aiki ne da ya fi yadda a cikin tsufa. Tare da shekaru a cikin mutane da kuma a cikin dabbobin catalase aiki a hankali rage-rage a sakamakon tsufa da kyallen takarda da kuma gabobin.

A cewar wani nazarin kwanan nan, a rage na catalase aiki ne daya daga cikin yiwu Sanadin gashi graying. Hydrogen peroxide aka samar ci gaba a jikin mutum, amma babu wata cũta - catalase decomposes shi da sauri. Amma idan matakin na wannan enzyme an rage, shi ne bayyananne cewa, ba duk da hydrogen peroxide aka catalyzed da enzyme. Saboda haka, shi discolors daga ciki da gashi ta rushe halitta dyes. Wannan m samu a halin yanzu ana gwada ta da masu bincike, da kuma iya taka rawa a ci gaban da kwayoyi, dakatar da graying na gashi.