Ua pa saw: haumxeeb enzymes

Tag nrho biochemical kev tig cev nyob rau hauv lub hlwb ntawm tej kab mob tshwm sim nrog lub zog expenditure. Ua pa saw - ib theem kev lug uas yog nyob rau ntawm lub puab membrane ntawm mitochondria thiab ua hauj lwm rau cov tsim ntawm ATP. Adenosine yog ib tug ntau yam chaw ntawm lub zog thiab muaj peev xwm noog lub 80 mus rau 120 kJ.

Ua pa electron saw - yog dab tsi?

Electrons thiab protons ua si ib qho tseem ceeb luag hauj lwm nyob rau hauv lub zog kawm ntawv. Lawv tsim ib tug voltage txawv rau ob tog ntawm daim nyias nyias ntawm lub mitochondria uas generates ib tug qhia cov lus tsa suab ntawm tus hais - tam sim no. Ua pa saw (nws ETC, electron thauj saw) yog ib tug neeg tuaj daws kho nyob rau hauv cov kev hloov ntawm qhov zoo them hais nyob rau hauv lub intermembrane qhov chaw thiab tsis zoo them hais nyob rau hauv lub thickness ntawm lub puab membrane ntawm mitochondria.

Lub ntsiab lub luag hauj lwm nyob rau hauv lub tsim ntawm lub zog belongs rau lub ATP-synthase. Qhov no complex set ntawm lub zog alters cov kev taw qhia ntawm cov proton tsab ntawv tsa suab nyob rau hauv lub biochemical zog ties. Los ntawm txoj kev, yog yuav luag zoo tib yam rau lub complex yog nyob rau hauv lub chloroplasts ntawm cov nroj tsuag.

Thiab ceg ntawm lub pa saw enzymes

Electron hloov lwm lub tsev yog nrog los ntawm biochemical kev tig cev nyob rau hauv lub xub ntiag ntawm lub enzyme system. Cov biologically active tshuaj, ntau cov ntawv luam ntawm cov uas tsim loj complex lug, ua hauj lwm raws li intermediaries nyob rau hauv cov kev hloov ntawm electrons.

Ceg ntawm lub pa saw - yog central Cheebtsam ntawm cov thauj ntawm them hais. Tag nrho cov nyob rau hauv lub puab mitochondrial membrane 4 yog xws tsim, raws li zoo raws li ATP synthase. Tag nrho cov lug koom ib lub hom phiaj - wrapping ETC electron hloov lwm lub tsev ntawm hydrogen protons nyob rau hauv lub intermembrane qhov chaw thiab, raws li ib tug tsim nyog tau, qhov synthesis ntawm ATP.

Cov ua yog ib tug sawv ntawm protein molecules, cov uas muaj enzymes, cov yam ntxwv thiab taw proteins. Txhua lub 4 ceg kom muaj raws li nws tsuas nws cov yam ntxwv, muaj nuj nqi. Cia peb kawm saib uas paub tab nyob rau hauv lub ETC tuaj cov lug.

kuv complex

Cov kev hloov ntawm electrons nyob rau hauv sab hauv ntawm lub mitochondrial membrane ntsiab luag hauj lwm no yog ua si los ntawm cov pa saw. Ntaus cov tshuaj tiv thaiv ntawm hydrogen protons thiab electrons nrog lawv - ib qho ntawm lub ntsiab tshua LWMYAM Ib tug thawj txheej ntawm thauj saw assumes molecule ntawm NAD * H + (nyob rau hauv cov tsiaj) los yog NADP * H + (nroj tsuag), ua raws li los ntawm cleavage ntawm cov plaub hydrogen protons. Ua tau, vim rau qhov cov complex biochemical cov tshuaj tiv thaiv kuv tseem hu ua NADH - dehydrogenase (lub npe central enzyme).

Muaj pes tsawg leeg dehydrogenase complex hlau-leej faj cov nqaijrog muaj xws li 3 hom, thiab flavin mononucleotide (FMN).

II complex

Lag luam ntawm no complex tsis koom nrog cov kev hloov ntawm hydrogen protons nyob rau hauv lub intermembrane qhov chaw. Lub ntsiab muaj nuj nqi ntawm cov qauv no yog muab ntxiv electrons mus rau lub electron thauj saw hlau los ntawm txoj kev succinate oxidation. Central enzyme complex - succinate-ubiquinone oxidoreductase, uas catalyzes lub cleavage ntawm electrons los ntawm succinic acid thiab hloov lwm lub tsev rau ubiquinone yog lipophilic.

Tsum ntawm hydrogen protons thiab electrons mus rau lub thib ob ua yog kuj fad * H _2. Txawm li cas los, flavin adenine dinucleotide efficiency tsawg tshaj li uas ntawm nws analogues - NAD los yog NADP * H * H.

Muaj pes tsawg leeg II muaj peb hom ntawm complex hlau-leej faj cov nqaijrog thiab central oxidoreductase enzyme succinate.

III complex

Cov tom ntej no kev tivthaiv ntawm cov nyiaj, ETC muaj cytochrome b ₅₅₆ b _560, thiab c _1, raws li zoo raws li hlau-leej faj protein Risk. Kev ua hauj lwm ntawm peb txheej yog txuam nrog rau cov kev hloov ntawm ob hydrogen protons nyob rau hauv lub intermembrane qhov chaw, thiab electrons los ntawm cov lipophilic ubiquinone rau cytochrome C.

Risk feature ntawm protein yog hais tias nws dissolves nyob rog. Lwm yam nqaijrog ntawm no pab pawg neeg uas tau ntsib nyob rau hauv lub ceg ntawm cov pa saw, dej-soluble. Qhov no feature muaj feem xyuam rau txoj hauj lwm ntawm cov protein molecules nyob rau hauv lub thickness ntawm lub puab mitochondrial membrane.

Qhov thib peb txheej zog raws li ubiquinone-cytochrome c oxidoreductase.

complex IV

Nws cytochrome-oxidant complex uas yog zaum kawg destination nyob rau hauv lub LWMYAM Nws txoj hauj lwm yog mus rau cov hloov electrons los ntawm cytochrome c rau cov pa atoms. Tom qab tsis zoo them O atoms yuav hnov mob nrog cov hydrogen protons tsim dej. Lub ntsiab enzyme - cytochrome c oxidoreductase oxygen.

Tus qauv ntawm cov plaub complex muaj xws li cytochrome ib tug, ib tug _3, thiab ob tug tooj liab atoms. Lub hauv paus luag hauj lwm nyob rau hauv cov kev hloov ntawm electrons rau oxygen mus cytochrome ib tug _3. Lub sis ntawm cov lug yog suppressed nitrogen cyanide thiab cov pa roj carbon monoxide, nyob rau hauv lub ntiaj teb no kev txiav txim zoo, nws ua rau yus lub txiav ntawm ATP synthesis thiab kev puas tsuaj.

ubiquinone

Ubiquinone - ib tug vitamin zoo li tshuaj yeeb dej caw, ib tug lipophilic compound, uas tsiv dawb nyob rau hauv lub thickness ntawm daim nyias nyias. mitochondrial pa saw yuav tsis ua li cas tsis cov qauv no, piv txwv li. k. Nws yog lub luag hauj lwm rau electron thauj los ntawm cov ceg kuv thiab II rau txoj III.

Ubiquinone yog ib tug benzoquinone derivative. Qhov no qauv yuav raug xa mus nyob rau hauv Schemes Q tsab ntawv los yog abbreviated haujlwm uas yog COy (lipophilic ubiquinone). Cov oxidation ntawm lub molecule ua mus rau tsim ntawm semiquinone - ib tug muaj zog oxidizer, uas yog muaj feem txaus ntshai rau lub cell.

ATP synthase

Lub ntsiab lub luag hauj lwm nyob rau hauv lub tsim ntawm lub zog belongs rau lub ATP-synthase. Qhov no qauv siv gribopodobnaya zog qhia cov lus tsa suab hais (protons) los hloov nws mus rau hauv tshuaj muaj zog.

Cov yooj yim txoj kev uas tshwm sim thoob plaws hauv lub ETC - yog oxidation. Cov pa saw yog lub luag hauj lwm rau electron thauj nyob rau hauv lub mitochondrial membrane thicker thiab lawv txuam nrog nyob rau hauv lub matrix. Ib txhij, lub ceg ntawm kuv, III thiab IV yog pumped hydrogen protons nyob rau hauv lub intermembrane qhov chaw. them nyiaj sib txawv nyob rau hauv lub sab ntawm daim nyias nyias ua rau directional zog ntawm protons los ntawm cov ATP synthase. Txij li thaum H + nkag mus rau matrix, electrons yog tau ntsib (uas yog txuam nrog rau oxygen) mus ua ib lub nyob nruab nrab tshuaj rau lub cell - dej.

ATP synthase F0 muaj thiab F1 subunits uas ua ke rau router molecule. F1 muaj peb peb alpha thiab beta subunits, uas ua ke tsim tau ib cov channel. Qhov no channel muaj raws nraim tib yam kab uas hla, uas muaj ib tug hydrogen protons. Nrog rau cov zaj uas zoo them hais los ntawm lub ATP synthase lub taub hau F ₀ molecules yog cov los ntawm 360 degrees ib ncig ntawm nws axis. Thaum lub sij hawm lub sij hawm no, mus AMP los yog ADP (adenozinmono- thiab diphosphate) txuas phosphate residue nrog ib tug high-zog bonds, uas puag ncig lub loj npaum li cas ntawm lub zog.

ATP synthase yog pom nyob rau hauv lub cev, tsis yog nyob rau hauv lub mitochondria. Nyob rau hauv cov nroj tsuag, cov ceg kuj nyob rau ntawm daim nyias nyias ntawm lub vacuoles (tonoplast), raws li zoo raws li lub chloroplast thylakoids.

Tsis tas li ntawd nyob rau hauv cov tsiaj hlwb thiab cog ATPases yog tam sim no. Lawv muaj ib tug uas zoo sib xws qauv raws li hais tias ntawm lub ATP synthase, tab sis lawv txiav txim yog hais rau tshem tawm ntawm phosphate residues mus rau lub expenditure ntawm lub zog.

Lub lom ntsiab lus ntawm qhov ua pa saw

Firstly, qhov kawg khoom ETC tshua yog lub thiaj li hu ua metabolic dej (300-400 ml ib hnub twg). Secondly, qhov synthesis ntawm ATP thiab lub zog cia nyob rau hauv biochemical bonds ntawm lub molecule. Thaum hnub 40-60 kg adenosine yog tsim, thiab tib yam yog siv nyob rau hauv enzymatic tshua hlwb. Lub neej ntawm ib tug qauv ntawm ATP yog 1 feeb, ces tus pa saw yuav tsum khiav haujlwm zoo, meej thiab tsis muaj kom raug. Txwv tsis pub, lub cell yuav tuag.

Mitochondria yog xam tau tias yog zog noj ntawm tej cell. Lawv tus xov tooj yog nyob rau hauv lub zog uas yuav tsum tau rau tej yam kev khiav dej num. Piv txwv li, neurons yuav raug suav mus txog 1000 mitochondria uas feem ntau tsim ib pawg nyob rau hauv lub synaptic thiaj li hu ua quav hniav.

Sib txawv ntawm cov pa saw nyob rau hauv cov nroj tsuag thiab cov tsiaj

Nyob rau hauv cov nroj tsuag, ib tug ntxiv "fais fab nroj tsuag" ntawm lub cell yog ib tug chloroplast. Nyob rau lub puab membrane ntawm cov organelles no tseem nyob ATP synthase, thiab qhov no yog ib qho kom zoo dua li tus tsiaj hlwb.

Tsis tas li ntawd cov nroj tsuag muaj peev xwm ciaj sia nyob rau hauv siab ntau ntawm cov pa roj carbon monoxide, nitrogen thiab cyanide vim cyanide-resistant txoj kev nyob rau hauv lub LWMYAM Ua pa saw li xaus rau ubiquinone, los ntawm uas electrons yog ncaj qha mus pauv mus rau lub oxygen atoms. Raws li ib tug tshwm sim, tsawg ATP yog tsim, txawm li cas los, cov nroj tsuag muaj peev xwm ciaj sia phiv tej yam kev mob. Tsiaj txhu nyob rau hauv xws li mob, heev raug tuag.

Peb yuav piv efficiency ntawm NAD, fad thiab cyanide-resistant txoj kev los ntawm cov ATP qhia tsim thaum Identify 1 electron.

• nrog NAD los yog NADP tsim los ntawm 3 molecules ntawm ATP;
• Fad yog tsim nrog ob molecules ntawm ATP;
• ntawm cyanide ntaub ntawv 1 sustainable txoj kev ATP molecule.

Evolutionary tseem ceeb ntawm ETC

Rau tag nrho eukaryotic kab mob, ib tug loj qhov chaw ntawm lub zog yog lub ua pa saw. Biochemistry ATP synthesis nyob rau hauv lub cell yog muab faib ua ob hom, substrate ntsev thiab oxidative ntsev. ETC yog siv nyob rau hauv lub synthesis ntawm ob hom ntawm lub zog, piv txwv li. E. Vim redox tshua.

Nyob rau hauv prokaryotic kab mob ATP tsim xwb nyob rau hauv substrate ntsev nyob rau hauv glycolysis theem. Rau-carbon suab thaj (dua li glucose) muab kev koom tes nyob rau hauv cov tshuaj tiv thaiv kev voj voog, thiab cov qhov tso zis cell tau txais ob molecules ntawm ATP. Qhov no hom ntawm lub zog yog pom tau hais tias yuav lub feem ntau txheej thaum ub synthesis, piv txwv li. K. Eukaryotes thaum lub sij hawm oxidative ntsev tsim 36 ATP molecules.

Txawm li cas los, qhov no tsis txhais hais tias hnub no lub nroj tsuag thiab cov tsiaj tau poob lub peev xwm los substrate ntsev. Cia li no hom ntawm ATP synthesis yog tus tsuas yog ib qho ntawm cov peb theem ntawm lub zog ntau lawm nyob rau hauv lub cell.

Glycolysis nyob rau hauv eukaryotes yuav siv sij hawm qhov chaw nyob rau hauv lub cytoplasm ntawm lub cell. Muaj tag nrho cov tsim nyog enzymes uas yuav muab siab npuab zib rau ob molecules ntawm pyruvic acid tsim 2 molecules ntawm ATP. Tag nrho cov tom ntej cov kauj ruam coj qhov chaw nyob rau hauv lub mitochondrial matrix. Krebs voj voog los yog lub tricarboxylic acid voj voog, raws li tshwm sim nyob rau hauv lub mitochondria. Qhov no kaw saw tshua raws li ib tug tshwm sim ntawm uas coj los ua ke NAD thiab fad * H * H2. Cov molecules yuav siv tau raws li ib tug consumable nyob rau hauv LWMYAM