Microsomal hadawan abu da iskar shaka: wani sa na halayen

Rawar da microsomal hadawan abu da iskar shaka a cikin rayuwar da kwayoyin da wuya a overestimate ko miss. Inactivation na xenobiotic (mai guba abubuwa) ga rushewar samuwar adrenal hormones da hannu a cikin metabolism sunadaran da kuma adana kwayoyin bayanai - ne kawai a kananan sulusi da murabba'i na san matsalolin da ake warware godiya ga microsomal hadawan abu da iskar shaka. Yana da wani m tsari a cikin jiki, wanda aka gudanar bayan da aka buga ta a jawo abu da kuma kawo karshen tare da elliminatsiey.

definition

Microsomal hadawan abu da iskar shaka - a cascade da halayen kunshe a cikin ta farko hira lokaci na xenobiotics. Jigon da tsari da yake a cikin hydroxylation abubuwa tare da oxygen kwayoyin zarra da form ruwa. Saboda da canje-canje a cikin tsarin asali abu, kuma da kaddarorin iya ko dai a danne ko Littafi.

Microsomal hadawan abu da iskar shaka daukan ka ga Tasrifu dauki. Wannan biyu lokaci canje na xenobiotics, karshen abin da data kasance aikin kungiyar ne a haɗe kwayoyin samar a cikin jiki. Wani lokacin samuwar matsakaici abubuwa da sa hanta cell lalacewa, necrosis da nama degeneration na Oncology.

Hadawan abu da iskar shaka oxidase irin

Microsomal hadawan abu da iskar shaka halayen faruwa waje na mitochondria da haka sun cinye kamar goma bisa dari na jimlar oxygen shigar da jiki. Key enzymes a cikin wannan tsari - oxidase. A cikin tsarin, da karfe kwayoyin halitta ne ba tare da m valence, kamar baƙin ƙarfe, molybdenum, jan, da dai sauransu, da kuma saboda haka suna iya yarda da electrons. A cikin cell oxidase located in takamaiman vesicles (peroxisomes) located a kan m mitochondrial membranes kuma a EPR (m endoplasmic reticulum). Substrate fadowa a kan peroxisome hasarar hydrogen kwayoyin, wanda suna a haɗe zuwa wani kwayoyin na ruwa ta samar da peroxide.

Akwai kawai biyar oxidases:

- monoaminooksigenaza (Mao) - taimaka wajen oxidize adrenaline da sauran biogenic amines samar da adrenal gland.

- diaminooksigenaza (DAO) - da hannu a cikin hadawan abu da iskar shaka na histamine (matsakanci na kumburi da kuma allergies), polyamines da diamines.

- L-amino acid oxidase (ie, levorotatory kwayoyin).

- D-amino acid oxidase (dextrorotatory kwayoyin).

- xanthine - oxidize adenine da kuma Bibyun (nitrogen da kwasfansu kunshe a cikin jigidar halittar DNA).

Tamanin da oxidase irin microsomal hadawan abu da iskar shaka kunshi a kawar da xenobiotics da inactivate ilimin aiki abubuwa. Ilimi peroxide yana da wani bactericidal mataki da inji tsarkakewa na Laifi ne gefen sakamako wanda occupies wani muhimmin wuri a tsakanin sauran effects.

Hadawan abu da iskar shaka oxygenase irin

Oxygenase irin dauki a cikin cell da aka ma faruwa a kan m endoplasmic reticulum da mitochondria membranes vneschnih. Wannan na bukatar takamaiman enzymes - oxygenase cewa tãyar da oxygen kwayoyin daga substrate, da kuma gabatar da shi a cikin oxidizable abu. Idan aiwatar daya oxygen zarra, da monooxygenase enzyme kira ko hydroxylase. A cikin hali na gabatar da biyu kwayoyin halitta (Ina nufin, da dukan mazaunan kwayoyin na oxygen), da enzyme aka kira diaksigenaza.

Oxygenase irin hadawan abu da iskar shaka dauki hada da wani ternary multienzyme hadaddun cewa halarci canja wuri na electrons da protons ne daga substrate bi ta kunnawa da oxygen. Wannan duka tsari na faruwa a tare da sa hannu na cytochrome P450, wanda zai har yanzu za a bayyana a cikin mafi daki-daki.

Misalai oxygenase irin halayen

Kamar yadda aka ambata a sama, monooxygenase for hadawan abu da iskar shaka amfani kawai daya oxygen zarra na biyu akwai. Na biyu, suna a haɗe zuwa biyu kwayoyin na hydrogen ta samar da ruwa. Daya misali na irin wannan dauki da samuwar collagen. oxygen bayarwa a wannan harka abubuwa a matsayin bitamin C. Prolingidroksilaza robs shi na oxygen kwayoyin da bãyar da ita ga proline, wanda a nuna shi ne wani ɓangare na procollagen kwayoyin. Wannan tsari yana da ƙarfi, kuma elasticity na connective nama. Lokacin da akwai wani rashi na bitamin C, da bunkasa gout. Yana bayyana da wani rauni daga cikin connective nama, zubar da jini, bruising, asarar hakora, wato, da ingancin collagen a cikin jiki ne da ke ƙasa.

Wani misali shi ne na hydroxylase cewa maida cholesterol kwayoyin. Wannan shi ne daya daga cikin matakai na samuwar steroid hormones, ciki har da jima'i.

ba takamaiman hydroxylase

Wannan hydrolase zama dole ga hadawan abu da iskar shaka daga kasashen waje abubuwa, kamar xenobiotics. Da ma'anar da halayen ne ya yi irin kayan more amenable ga kau, mafi narkewa. Wannan tsari shine ake kira detoxification, kuma shi ya auku mafi yawa a cikin hanta.

By yin amfani da dukan kwayoyin na oxygen da aka samar a cikin rata xenobiotics sake zagayowar halayen da kuma bazuwar daga cikin hadaddun abu a cikin da dama mafi sauki da kuma samuwa ga tafiyar matakai na rayuwa.

Mai amsawa oxygen jinsunan

Oxygen ne yiwuwar hatsari abu, tun da, a gaskiya, da hadawan abu da iskar shaka - mai konewa tsari. A cikin irin Yã ₂ kwayoyin, ko ruwa ne barga, kuma chemically inert, saboda ta ikon matakin suna cike da sabon electrons ba zai iya shiga. Duk da haka, mahadi a cikin abin da oxygen ba a duk akwai wani biyu daga electrons da high reactivity. Saboda haka aka kira su aiki.

Irin wannan oxygen mahadi:

1. A monooksidnyh halayen samar superoxide wanda aka rabu da cytochrome P450.
2. A oxidase halayen ne da samuwar peroxide anion (hydrogen peroxide).
3. A lokacin sake oxygenation daga kyallen takarda, wadda aka yi mashi ischemia.

A mafi yawan iko oxidizer ne hydroxyl m, shi wanzu a wani free form kawai milyan na biyu, amma a wannan lokacin da lokacin da za a je ta hanyar yawan hadawan abu da iskar shaka halayen. Its alama ne cewa hydroxyl m rinjayar da abu kawai a wuri a cikin abin da aka kafa, kamar yadda ba zai iya shiga cikin masana'anta.

Superoxide anion da hydrogen peroxide

Wadannan abubuwa ne aiki ba kawai a bangaren ilimi, amma kuma a wasu nesa daga gare su, kamar yadda suka iya shiga ta hanyar da jikin tantanin.

Hydroxyl kungiyar sa da hadawan abu da iskar shaka daga cikin amino acid sharan: histidine, cysteine da tryptophan. Wannan take kaiwa zuwa inactivation na enzyme tsarin, kazalika da rushewa daga cikin kai da sunadarai. Bugu da kari, microsomal hadawan abu da iskar shaka da amino acid din take kaiwa zuwa lalata tsarin nucleic nitrogenous tushe, saboda haka, sha kwayoyin na'ura na cell. Kuma oxidized m acid da cewa yin up da cell membranes bilipidnogo Layer. Wannan rinjayar da permeability, aiki electrolyte membrane famfo da kuma wurin da tsoka mai amsa sigina.

Hanawa na microsomal hadawan abu da iskar shaka - ne antioxidants. Aka sãme su a abinci da ake samar a cikin jiki. A mafi yawan sanannun antioxidant ne bitamin E. Wadannan abubuwa za su iya hana microsomal hadawan abu da iskar shaka. Biochemistry bayyana hulda tsakanin su a kan tushen da feedback. Wannan ne, da mafi oxidases, da more suna mur, da kuma mataimakin versa. Wannan taimaka wajen kula da sikẽli tsakanin tsarin da haƙuri da ciki yanayi.

lantarki kai sarkar

Microsomal hadawan abu da iskar shaka tsarin ba narkewa a cikin cytoplasm na gyara don haka da cewa duk da enzymes suna tattara a farfajiya na endoplasmic reticulum. Wannan tsarin hada da dama sunadarai, wanda ya samar da da electrotransport kewaye:

- NADPH-P450 reductase da cytochrome P450.

- kan-tsitohromV5 reductase da cytochrome B5.

- steatorrhea-CoA desaturase.

A electron bayarwa a yawancin lokuta ayyukan NADP (nicotinamide adenine dinucleotide phosphate). Yana oxidizes NADPH-P450 reductase, wanda qunshi biyu coenzyme (fad da FMN), don shan electrons. A karshen sarkar FMN oxidized amfani P450.

cytochrome P450

Wannan enzyme na microsomal hadawan abu da iskar shaka na heme-dauke da gina jiki. Yana binds oxygen da kuma wani substrate (yawanci a xenobiotic). Its sunan ake dangantawa da sha na haske da wani zango na 450 nm. Ilmin halitta sun gano shi a duk rayayyun kwayoyin halitta. A lokacin, ya bayyana fiye da goma sha dubu sunadarai na da cytochrome P450 tsarin. A kwayoyin cuta, da abu ne narkar da a cytoplasm, kuma an yi imani da cewa wannan tsari ne mafi evolutionarily tsoho fiye da na mutane. Mun cytochrome P450 - a mural gina jiki gyarawa a kan cytoplasmic membrane.

A enzymes na wannan kungiya suna da hannu a cikin metabolism na steroids da bile m acid, phenols, neutralizing kwayoyi, poisons ko kwayoyi.

Da kaddarorin microsomal hadawan abu da iskar shaka

A matakai na microsomal hadawan abu da iskar shaka da m substrate bayani dalla-dalla, kuma wannan, bi da bi, damar gane iri-iri abubuwa. Goma sha dubu sunadaran cytochrome P450 za a iya folded a fiye da ɗari da hamsin isoforms na enzyme. Kowace daga cikinsu yana da babban yawan substrates. Wannan damar jiki zuwa rabu da kusan dukkan abubuwa masu cutarwa da aka kafa a ciki ko fada a waje. Samar a cikin hanta microsomal hadawan abu da iskar shaka enzymes iya aiki a gida da kuma a wani babba nesa daga jiki.

A tsari na aiki na microsomal hadawan abu da iskar shaka

Microsomal hadawan abu da iskar shaka a cikin hanta da aka kayyade a cikin mRNA matakin, amma kuma wajen da aiki - kwafi. Duk bambance-bambancen karatu na cytochrome P450, misali, da ke rubuce a kan jigidar halittar DNA, kuma zuwa gare shi ya bayyana a ranar ESR zama dole to "sake rubutawa" da bayanai daga DNA to Manzo RNA. Sa'an nan mRNA ne zuwa ga ribosome inda sunadarai na gina jiki suna kafa. Yawan wadannan kwayoyin da aka kayyade daga waje da kuma shi ne dogara a kan adadin abubuwa wanda dole ne a kashe, da kuma kasancewa da muhimmanci amino acid.

A halin yanzu, fiye da ɗari biyu da hamsin da aka bayyana sinadaran mahadi da cewa kunna jiki microsomal hadawan abu da iskar shaka. Wadannan sun hada da barbiturates, aromatic hydrocarbons, alcohols, ketones kuma ji ba gani. Duk da wannan fili bambancin, duk wadannan abubuwa ne lipophilic (narkewa a cikin fats), sabili da haka mai saukin kamuwa zuwa cytochrome P450.