L-Cysteine (CAS # 52-90-4)
| Hazard Cov Cim | Xn – Ua phem |
| Risk Codes | R22 - Ua phem yog tias nqos R36/37/38 - Kab mob rau qhov muag, ua pa thiab tawv nqaij. |
| Kev nyab xeeb piav qhia | S26 - Thaum sib cuag nrog lub qhov muag, yaug tam sim ntawd nrog dej txaus thiab nrhiav kev kho mob. S37/39 - Hnav cov hnab looj tes tsim nyog thiab tiv thaiv qhov muag / ntsej muag |
Taw qhia
L-cysteine (L-Cysteine) yog ib qho tsis tseem ceeb amino acid, encoded los ntawm codons UGU thiab UGC, thiab yog sulfhydryl-muaj amino acid. Vim muaj cov pab pawg sulfhydryl, nws cov toxicity yog me me, thiab raws li ib qho antioxidant, nws tuaj yeem tiv thaiv kev tsim cov dawb radicals. & & L-cysteine yog ib txwm tshwm sim tsis tseem ceeb amino acid. Nws yog tus activator ntawm NMDA. Nws kuj ua tau ntau lub luag haujlwm hauv kab lis kev cai ntawm tes, raws li hauv qab no: 1. Protein synthesis substrate; Cov pab pawg sulfhydryl hauv cysteine ua lub luag haujlwm tseem ceeb hauv kev tsim cov disulfide daim ntawv cog lus, thiab tseem yog lub luag haujlwm rau folding ntawm cov proteins, tiam ntawm cov txheej txheem theem nrab thiab theem nrab. 2. Acetyl-CoA synthesis; 3. tiv thaiv hlwb los ntawm oxidative kev nyuaj siab; 4. yog qhov tseem ceeb ntawm leej faj hauv cov kab lis kev cai ntawm tes; 5. Hlau ionophore. & & Kev ua haujlwm lom neeg: Cysteine yog ib qho polar α-amino acid uas muaj sulfhydryl pawg hauv aliphatic pawg. Cysteine yog ib qho tseem ceeb ntawm cov amino acid thiab saccharogenic amino acid rau tib neeg lub cev. Nws tuaj yeem hloov pauv los ntawm methionine (methionine, qhov tseem ceeb amino acid rau tib neeg lub cev) thiab tuaj yeem hloov mus rau hauv cystine. Lub decomposition ntawm cysteine yog decomposed rau hauv pyruvate, hydrogen sulfide thiab ammonia los ntawm kev ua ntawm desulphurase nyob rau hauv anaerobic tej yam kev mob, los yog los ntawm transamination, intermediate khoom β-mercaptopyruvate decomposed rau hauv pyruvate thiab sulfur. Nyob rau hauv cov xwm txheej oxidation, tom qab oxidized rau cysteine sulfurous acid, nws tuaj yeem decomposed rau hauv pyruvate thiab sulfurous acid los ntawm transamination, thiab decomposed rau hauv taurine thiab taurine los ntawm decarboxylation. Tsis tas li ntawd, cysteine yog ib qho tsis ruaj khov, yooj yim redox, thiab cuam tshuam nrog cystine. Nws tuaj yeem ua rau condensed nrog cov tshuaj lom neeg muaj ntxhiab los ua ke mercapturic acid kom detoxify. Cysteine yog ib qho kev txo qis, uas tuaj yeem txhawb kev tsim gluten, txo lub sij hawm xav tau rau kev sib xyaw thiab lub zog xav tau rau kev siv tshuaj. Cysteine tsis muaj zog rau cov qauv ntawm cov protein los ntawm kev hloov cov disulfide bonds ntawm cov protein molecules thiab hauv cov protein molecules, kom cov protein stretches.
