Microsomal namachibi: iqoqo ukusabela

Indima microsomal namachibi emphilweni umzimba kunzima overestimate noma miss. Inactivation ka xenobiotic (ezinobuthi), wokugoqa kanye kumiswa hormone adrenal ehilelekile umzimba amaprotheni kanye nokulondolozwa ukwaziswa kwezakhi zofuzo - sibonga encane lwezinkinga ezaziwayo kuphela isixazululekile ukuba microsomal namachibi. Kuyinto inqubo ezizimele emzimbeni, okuyinto ngimlandele yokushayiswa into inhlamvu ziphethe elliminatsiey yakhe.

definition

Microsomal namachibi - kubangela ukusabela kufakwe ukuguqulwa Isigaba sokuqala xenobiotics. Ingqikithi inqubo itholakala hydroxylation izinto nge-athomu omoya-oxygen ne amanzi fomu. Ngenxa yezinguquko isakhiwo amathambo emvelo, futhi izakhiwo zalo lingasethelwa ukuyiveza noma iyakhula.

Microsomal namachibi kukuthatha ukuphendula conjugation. Lesi sigaba kugucuka wesibili ka xenobiotics, ekupheleni okuyinto neqembu elikhona obusebenzayo unamathele molecule ekhiqizwa phakathi nomzimba. Ngezinye izikhathi kumiswa izinto eziphakathi ezibangela isibindi cell umonakalo, necrosis nezicubu ukonakala of Oncology.

Namachibi oxidase uhlobo

Microsomal namachibi ukusabela zenzeka ngaphandle kwe-mitochondria ngakhoke aphele cishe eziyishumi amaphesenti oxygen Imininingwane engena emzimbeni. enzyme Key kule nqubo - oxidase. Uma sibheka ukwakheka kwazo yabo, ama-athomu metal abakhona nge Valence ziyinani elifanayo, njengokudla yensimbi, molybdenum, ithusi, njll, futhi ngaleyo bayakwazi ukwamukela ama-electron. Esikhathini oxidase cell elise ethize vesicles (peroxisomes) esisogwini yangaphandle ulwelwesi mitochondrial futhi EPR (anolaka reticulum endoplasmic). Substrate ehlela phezu peroxisome ilahlekelwa hydrogen amangqamuzana, okuyinto anamekwe molecule yamanzi ukwakha peroxide.

Kukhona oxidases emihlanu kuphela:

- monoaminooksigenaza (mao) - kuyasiza oxidize adrenaline nezinye ama biogenic ekhiqizwa nezindlala adrenal;

- diaminooksigenaza (Dao) - abathintekayo kulo namachibi of histamine (umlamuleli ukuvuvukala komzimba), polyamines futhi diamines;

- L-amino acid oxidase (ie, amangqamuzana omoya levorotatory);

- D-amino acid oxidase (molecule dextrorotatory);

- xanthine - oxidize adenine ihambisane ne-guanine (nitrogen elisekela kufakwe molecule ye-DNA).

Inani oxidase uhlobo microsomal namachibi siqukethe ekuqedweni xenobiotics futhi okunqanda izinto eziphila abakhuthele. Ezemfundo peroxide has a isinyathelo amagciwane nokuhlanzwa mechanical iphutha iyona side effect okuyinto zisendaweni ebalulekile phakathi eminye imiphumela.

Namachibi oxygenase uhlobo

Oxygenase uhlobo ukusabela kweselula futhi ezenzeka emangelengele reticulum endoplasmic futhi mitochondria ulwelwesi vneschnih. Lokhu kudinga enzyme ethize - oxygenase ukuthi ukukhulisa engqamuzaneni oksijini evela substrate, nekungeniswa kube ketshezi oxidizable. Uma lwenteke eyodwa yomoya-mpilo-athomu, enzyme monooxygenase ngokuthi noma hydroxylase. Endabeni ethula athomu amabili (ngamanye amazwi, i-molecule wonke umoya-mpilo), i-enzyme ibizwa ngokuthi i diaksigenaza.

Oxygenase uhlobo namachibi ukuphendula kufaka ternary multienzyme eziyinkimbinkimbi iqhaza ku ukudluliselwa electron nama-proton kusukela substrate kulandele ukusebenza komoya-mpilo. Yonke le nqubo kwenzeka iqhaza cytochrome P450, okuyinto isazoqhubeka kuchazwe kabanzi.

Izibonelo oxygenase khambi

Njengoba kushiwo ngenhla, monooxygenase ngoba namachibi ukusetshenziswa eyodwa kuphela-mpilo athomu amabili etholakalayo. Okwesibili, basuke enamathiselwe ezimbili molecule hydrogen ukuze akha amanzi. Esinye isibonelo ukusabela ngaleyo ndlela Ukwakheka collagen. umoya-mpilo donor kuleli cala uba vitamin C odingekayo ngosuku Prolingidroksilaza komphangayo ke ka-mpilo futhi okunika proline, nakho kuyingxenye engqamuzaneni procollagen. Le nqubo unika amandla futhi kuyaqina zezicubu zezinzwa. Lapho kukhona ukuntula uvithamini C, i-sifo asathuthuka. Kubonisa ngobuthakathaka ezicutshini, ukopha, nokulimala, ukuphuma amazinyo, okungukuthi, ikhwalithi ye-collagen emzimbeni ingezansi.

Esinye isibonelo hydroxylase ukuthi ukuguqula cholesterol-molecule. Lona omunye izigaba kumiswa hormone steroid, kuhlanganise ocansini.

akuyona hydroxylase ethize

Lokhu hydrolase adingekayo ukuze namachibi izidakamizwa bezinye izizwe, njenge xenobiotics. Okwakushiwo ukusabela ukwenza izinto ezinjalo amenable ngaphezulu ukususwa, encibilikayo ngaphezulu. Le nqubo ibizwa ngokuthi ngokukhishwa kobuthi egazini, futhi kwenzeka ikakhulukazi esibindini.

Ngokusebenzisa wonke molecule-mpilo ikhiqizwa esikhaleni xenobiotics umjikelezo ukusabela kanye noqhekeko we ketshezi eziyinkimbinkimbi ku eziningana okulula futhi iyatholakala izinqubo umzimba.

zinhlobo oksijini esisheshayo

Oxygen kuyinto into yingozi, njengoba, eqinisweni, namachibi - inqubo amandla omlilo. Ngesimo O ₂ molecule noma amanzi uzinzile futhi inert amakhemikhali, ngoba amandla ayo ezingeni zigcwele futhi electron entsha Awukwazi ukujoyina. Nokho, compounds lapho umoya-mpilo neze kukhona pair of electron babe reactivity okusezingeni eliphezulu. Ngakho-ke babizwa asebenzayo.

umoya-mpilo okunjalo compounds:

1. Ngo ukusabela monooksidnyh ekhiqizwa superoxide okuyinto ahlukaniswa P450 cytochrome.
2. Ukusabela oxidase Ukwakheka kwezitho anion peroxide (i-hydrogen peroxide).
3. Phakathi kabusha oxygenation kwezicubu, okuyinto kwavele ischemia.

I oxidizer enamandla kakhulu kuyinto olukhulu hydroxyl, ikhona ifomu mahhala nje kweziyisigidi yomzuzwana, kodwa ngaleso sikhathi babe nesikhathi zidlule eziningana namachibi ukusabela. Sici Its wukuthi olukhulu hydroxyl kuthinta ketshezi kuphela endaweni kwakheka okuyinto, njengoba abakwazi ukungena lendwangu.

anion Superoxide futhi i-hydrogen peroxide

Lezi izinto abakhuthele hhayi kuphela endaweni imfundo, kodwa futhi ukuqhela kwabo, njengoba bengeke bakwazi ukungena ngokusebenzisa ulwelwesi cell.

iqembu hydroxyl kubangela namachibi of izinsalela acid acid: histidine, cysteine futhi tryptophan. Lokhu kuholela inactivation izinhlelo enzyme, kanye ukuphazamiseka namaprotheni ezokuthutha. Ngaphezu kwalokho, microsomal namachibi of amino acid kuholela ekubhujisweni isakhiwo isizinda nucleic nitrogen, futhi ngenxa yalokho, sihlupheke apharathasi zofuzo engqamuzaneni. Futhi oxidized fatty acid ezakha cell ulwelwesi bilipidnogo ungqimba. Lokhu kuthinta permeability zabo, umsebenzi electrolyte ulwelwesi futha indawo yokwamukela.

Inhibitors ka microsomal namachibi - kukhona Antioxidants. Atholakala ukudla futhi kukhiqizwa ngaphakathi emzimbeni. I antioxidant kakhulu owaziwa Vitamin E. Lezi izinto singavimbela microsomal namachibi. Biochemistry uchaza ukuxhumana phakathi kwazo ngesisekelo impendulo. Okungukuthi, abangabantwana oxidases okwengeziwe, kulapho basuke ukuyiveza, futhi okuphambene nalokho. Lokhu kusiza ukuba silondoloze ukulinganisela phakathi izinhlelo kanye ukuqinisela imvelo yangaphakathi.

kagesi ezokuthutha chain

Microsomal namachibi uhlelo akuyona oncibilikayo le cytoplasm yezingxenye ukuze wonke enzyme yayo ziqoqwa phezu kobuso reticulum endoplasmic. Lolu hlelo kuhlanganisa amaprotheni amaningi, akha isifunda electrotransport:

- NADPH-P450 reductase futhi cytochrome P450;

- PHEZU-tsitohromV5 reductase futhi cytochrome B5;

- steatorrhea-CoA desaturase.

I donor electron e iningi izimo izenzo NADP (nicotinamide adenine ihambisane dinucleotide phosphate). It oxidizes NADPH-P450 reductase, okuyindawo ehlanganisa coenzyme ezimbili (mkhuba futhi FMN), ngokuthatha electron. Ekupheleni iketango FMN oxidized usebenzisa P450.

cytochrome P450

Lokhu enzyme we namachibi microsomal wamaprotheni i-heme-aqukethe. It lubopha oxygen ne substrate (ngokuvamile xenobiotic). Igama layo lihlotshaniswa ukumuncwa ukukhanya nge wavelength 450 nm. Izazi zezinto eziphilayo ziye zathola kuyo zonke izinto eziphilayo. Okwamanje, echazwe ngaphezulu kuka nanye ayizinkulungwane amaprotheni okuqondene uhlelo cytochrome P450. Ngo-bacterium, ketshezi siphela ku cytoplasm, futhi kunenkolelo yokuthi le fomu endala kakhulu evolutionarily kunowabantu. Thina cytochrome P450 - iprotheni mural zigxilé ulwelwesi cytoplasmic.

I-enzyme yaleli qembu zinengxenye umzimba kwezidakamizwa kanye Bile-fatty acid, phenols, zokuyithena izidakamizwa, ubuthi noma izidakamizwa.

I izakhiwo microsomal namachibi

Izinqubo of microsomal namachibi abe ezibanzi substrate ngokucacile, futhi lokhu, esikhundleni salokho, kuvumela ukuthola ezihlukahlukene izinto. amaprotheni ayizinkulungwane Eleven P450 cytochrome kungenziwa eligoqiwe ezingaphezu kweyodwa namashumi amahlanu isoforms of enzyme. Ngamunye wabo has inqwaba substrates. Lokhu kwenza umzimba ukuqeda cishe zonke izidakamizwa eziyingozi okuyinto akhiwa ngaphakathi noma ziphumela ngaphandle. Ukukhiqiza esibindini microsomal namachibi enzyme bangase benze kuzo ngaphakathi ezweni nakumazwe at amabanga amade uma liya kusuka emzimbeni.

Ukulawulwa umsebenzi microsomal namachibi

Microsomal namachibi esibindini ulawulwa ezingeni mRNA, kodwa kunalokho umsebenzi walo - umbhalo. Zonke okuhlukile cytochrome P450, isibonelo, owalotshwa lapho molecule ye-DNA, futhi kwakubonakala sengathi ku ESR ezidingekayo "ubhale" ulwazi kusuka DNA isithunywa RNA. Khona-ke mRNA siqondiswe ribosome lapho akhiwa amaprotheni molecule. Inani la mangqamuzana ulawulwa kusukela ngaphandle luncike inani izinto okumele isasebenza, futhi ukutholakala ebalulekile amino acid.

Okwamanje, engaphezu kwamakhulu amabili namashumi ayisihlanu-echazwe chemical compounds ukuthi kusebenze namachibi umzimba microsomal. Lezi zihlanganisa barbiturates, hydrocarbon elimnandi, alcohols, ketones futhi hormone. Naphezu kwakho konke lokhu ukwehluka sobala, zonke lezi izinto kukhona lipophilic (oncibilikayo amafutha), futhi ngenxa yalokho ukungenwa cytochrome P450.