I-CYANOCOBALAMIN (IVITAMIN B12)
Imilo kunye neempawu
Le mveliso yikristale ebomvu okanye i-crystalline powder, ayinavumba, ayinancasa kwaye ineempawu ezinamandla zokufunxa umswakama. Inyibilika kancinci emanzini okanye kwi-ethanol, ayinyibiliki kwi-chloroform okanye kwi-ether. Ayinakumelana nobushushu, kodwa isenokungasebenzi xa ivezwa kwizinto ezikhupha i-oxidizing okanye ezinciphisa ubushushu (ezifana ne-vitamin C okanye i-hydrogen peroxide, njl.njl.), iityuwa zesinyithi esinzima kunye nee-asidi ezinamandla kunye ne-alkalis ezinamandla.
Ulwakhiwo lweKhemikhali
I-Vitamin B12 yi-equioctaphedral compound equlethe ii-ion ze-cobalt. Ulwakhiwo lwayo oluphakathi yi-flat corrin ring eyenziwe zii-pyrroles ezine ezidityanisiweyo. Iimolekyuli ze-vitamin B12 zenziwe malunga namacandelo ama-3: i-gourin ring e-chylated yi-atoms ezine ze-N kunye nee-ion ze-cobalt eziphakathi; i-5,6-dimethylbenzimidazole (5,6-dimethylbenzimidazole, DMBI) edityaniswe nee-atoms ze-N-7 kunye nee-ion ze-cobalt njengeemolekyuli ze-vitamin B 12 ze-low-level (α) ligands. Ukongeza, i-DMBI ikwadityaniswe ne-aminopropanol ngamaqela e-phosphate, kwaye i-aminopropanol idityaniswe ngokudibeneyo kwi-chain ye-propionic acid ecaleni kwi-pyrrole D; iqela le-adenosyl okanye iqela le-methyl. Idityaniswe nee-ion ze-cobalt ukwenza i-ligand ephezulu (β) yeemolekyuli ze-vitamin B12. Iintlobo ezahlukeneyo zezinto ze-vitamin B12 zenziwa xa iqela le-chemical book lahlukile kwi-high chemical book kwi-axis ye-goline ring. Iqela le-hydroxyl (-OH) liqhagamshelwe kwi-cobalt ion kwiringi ye-gluline ukuze lenze i-hydroxycobalamin. Ngokufanayo, i-deoxyadenosine (5'-deoxyadenosyl), i-methyl (-CH3), i-cyanide (-CN) kunye nee-ion ze-cobalt ziqhagamshelwe ukuvelisa i-adenosine cobalt ngokulandelelana. I-Amine (deoxyadenosylcobalamin), i-methylcobalamin (methylcobalamin) kunye ne-cyanocobalamin (cyanocobalamin). Kwindalo, uhlobo lokugqibela lwe-vitamin B12 biosynthesis yi-microorganisms yi-adenosine cobalamine (coenzyme B12), i-methyl cobalamine kunye ne-hydroxycobalamine. Nangona kunjalo, ngenxa yokuba iipropati zazo azizinzanga kakhulu, i-sodium cyanide yongezwa ngokwenziwa kwinkqubo yokucoca imboni ukuguqula uhlobo lwendalo lwe-vitamin B12 lube yi-cyanocobalamin ezinzileyo ngakumbi.
Umsebenzi wePhysiological
Phucula izinga lokusetyenziswa kwe-folic acid, ukwenziwa kwe-meththionine (eyenziwe kwi-cysteineine ephezulu) kunye ne-choline ene-folic acid, kunye nokwenziwa kwe-cyanocobalamin precursors ezifana ne-methyl coballamin kunye ne-coenzyme B12 kwinkqubo yokuvelisa i-prine kunye ne-pyrimidine, kwaye uthabathe inxaxheba kwinkqubo ye-methylation yeekhompawundi ezininzi ezibalulekileyo. Xa i-vitamin B12 inqongophele, umsebenzi wokudlulisa amaqela e-methyl kwi-methyl tetrahydrofolic acid uyancitshiswa, okwenza i-folic acid ibe yindlela engasetyenziswayo, ekhokelela ekuswelekeni kwe-folic acid. Gcina imetabolism kunye nomsebenzi we-nerve myelin sheath. Ukunqongophala kwe-vitamin B12 kunokubangela iingxaki ze-neurological, ukuwohloka komgogodla, kunye ne-chemical book kunokubangela iimpawu ezinzulu zengqondo. Ukunqongophala kwe-Vitamin B12 kunokukhokelela kwi-peripheral neuritis. Iimpawu zokuqala zokunqongophala kwe-vitamin B12 ebantwaneni ziimvakalelo ezingaqhelekanga, ukubonakaliswa okucothayo, ukuphendula kancinci, kwaye ekugqibeleni kukhokelela kwi-anemia. Khuthaza uphuhliso kunye nokuvuthwa kweeseli ezibomvu zegazi. I-Methylpropandiyl coenzyme A iguqulwa ibe yi-succinoyl coenzyme A kwaye ithatha inxaxheba kumjikelo we-tricarboxylic acid, apho i-succinyl coenzyme A inxulumene nokwenziwa kwe-heme. I-Vitamin B12 ikwathatha inxaxheba ekwenziweni kwe-deoxynucleic acid (DNA), imetabolism yamafutha, iicarbohydrate kunye neeproteni, kwaye inyusa ukwenziwa kwe-nucleic acids kunye neeproteni.
