Qhov twg protein synthesis tshwm sim? Lub essence ntawm tus txheej txheem, thiab qhov chaw ntawm cov protein synthesis nyob rau hauv lub cell

Tus txheej txheem ntawm protein biosynthesis yog tsis tshua muaj ib qho tseem ceeb rau lub cell. Vim hais tias cov nqaijrog muaj txoj tshuaj uas ua si ib tug siv lub luag hauj lwm nyob rau hauv cov ntaub so ntswg, lawv yog irreplaceable. Vim li no, nyob rau hauv tag nrho cov cell dab siv saw protein biosynthesis, uas hais nyob rau hauv ob peb organelles. Qhov no kom hais tias lub cell tu tub tu kiv thiab tau ntawm cov hav zoov.

NTSIAB protein biosynthesis

Lub chaw cov synthesis ntawm cov nqaijrog - yog ib tug ntxhib endoplasmic reticulum. Ntawm no yog lub ib thooj ntawm ribosomes, uas yog lub luag hauj lwm rau tsim ntawm ib tug polypeptide saw. Txawm li cas los, ua ntej rau theem ntawm translation (protein synthesis), yuav tsum tau ua kom ntawm lub noob, uas khw muag khoom cov lus qhia txog cov qauv ntawm cov protein pib. Tom qab ntawd, qhov no feem yuav tsum tau luam DNA (los yog RNA, thaum saib cov kab mob biosynthesis).

Tom qab ib tug DNA daim qauv ntawm RNA yuav tsum tau cov creation ntawm ib tug ntaub ntawv txheej txheem. Nyob rau lub hauv paus ntawm nws cov protein synthesis yuav raug nqa tawm ntawm lub saw. Thiab tag nrho cov kauj ruam uas tshwm sim uas nucleic acids, yuav tsum muab qhov chaw nyob rau hauv lub cell nucleus. Txawm li cas los, qhov no yog tsis ib qho chaw qhov twg protein synthesis tshwm sim. Qhov no qhov chaw, uas yog npaj rau lub biosynthesis.

Ribosomal protein biosynthesis

Main qhov chaw nyob qhov twg cov protein synthesis - nws ribosome, cell organelle, muaj raws ntawm ob subunits. Tej lug nyob rau hauv lub cell ib tug lossis loj npaum li cas, thiab lawv mas nyob rau hauv lub week ntawm lub ntxhib endoplasmic reticulum. biosynthesis nws tus kheej yog raws li nram no: nyob rau hauv lub cell nucleus tsim tub txib RNA mus los ntawm lub nuclear pores rau hauv lub cytoplasm thiab muaj raws li cov lub ribosome. Ces mRNA yog thawb mus rau hauv cov kis ntawm tus ribosome subunits, whereupon lub fixation ntawm cov thawj amino acid.

Mus rau qhov chaw nyob qhov twg cov protein synthesis, amino acids yog nkag los ntawm txoj kev hloov mus rau lwm RNA. Ib tug xws li ib molecule yuav ris ib amino acid. Lawv koom ib lub sij hawm nyob rau ib theem zuj zus ntawm cov tub txib RNA codons. Tsis tas li ntawd, lub synthesis yuav nres ib pliag.

Thaum tsiv raws lub mRNA, lub ribosome yuav tau txais mus rau hauv lub qhov chaw (introns) uas tsis encode amino acids. Nyob rau hauv cov qhov chaw, ib tug ribosome tsiv raws mRNA, tab sis yog tsis muaj cov amino acid tas li ntawd mus rau lub saw. Sai li sai tau raws li lub ribosome nce mus txog lub exon uas yog, qhov chaw, uas encodes lub acid, ces nws yog dua txuas mus rau lub polypeptide.

Postsynthetic kev hloov kho ntawm cov nqaijrog

Tom qab kho kom sawvdaws xeeb lub tsheb codon ntawm lub ribosome mRNA direct synthesis txheej txheem xaus. Txawm li cas los ua qauv muaj ib tug thawj qauv thiab tseem yuav tsis ua zog tseg rau nws. Nyob rau hauv thiaj li yuav kom ua, cov molecule yuav tsum tau ib lub koom haum nyob rau hauv ib tug tej yam qauv: theem nrab, tertiary los yog txawm ntau - quaternary.

Cov yam ntxwv lub koom haum ntawm cov protein

Secondary qauv - tus thawj theem ntawm cov yam ntxwv lub koom haum. Mus cuag cov thawj polypeptide saw yuav tsum spiralized (tsim alpha-helix) los yog bent (los ua ib tug beta-khaubncaws sab nraud povtseg). Ces, nyob rau hauv thiaj li yuav coj li txawm tsawg qhov chaw raws qhov ntev ntawm lub molecule ntau rub ua ke thiab lub qhov txhab mus rau hauv ib lub pob los ntawm hydrogen, covalent thiab ionic bonds, raws li zoo raws li lub interatomic kev sib tshuam. Yog li, ib tug globular cov protein.

Quaternary protein qauv

Lub quaternary qauv yog tus yam tag nrho. Nws muaj ob peb seem nrog ib tug globular qauv txuas fibrillar polypeptide strands. Nyob rau hauv tas li ntawd, tertiary thiab quaternary qauv yuav comprise ib tug carbohydrate los yog lipid residue, uas nthuav lub ntau yam ntawm cov protein zog. Nyob rau hauv kev, glycoproteins, complex sib txuas ntawm ib tug protein thiab ib tug carbohydrate yog immunoglobulins thiab ua ib tug tiv thaiv muaj nuj nqi. Tsis tas li ntawd glycoproteins nyob rau lub week ntawm lub hlwb thiab receptors ua hauj lwm. Txawm li cas los, tsis muaj hloov molecule nyob qhov twg protein synthesis tshwm sim, thiab nyob rau hauv lub du endoplasmic reticulum. Ntawm no nws yog tau lipid Symptoms, co, thiab carbohydrates rau protein thawj.