ATP synthesis: nta ntawm tus txheej txheem no

Zog metabolism, uas yuav siv sij hawm qhov chaw nyob rau hauv tag nrho cov hlwb ntawm ib tug nyob kab mob, hu ua dissimilation. Nws yog ib tug sau ntawm decomposition tshua ntawm organic tebchaw, nyob rau hauv uas ib qhov nqi ntawm lub zog tso.

Dissimilation yuav siv sij hawm qhov chaw nyob rau hauv ob los yog peb theem, nyob ntawm seb lub hom uas muaj sia nyob. Yog li, nyob rau hauv aerobic zog metabolism muaj kev npaj, anoxic thiab oxygen theem. Nyob rau hauv anaerobes (kab mob uas muaj peev xwm sawv ntawm ua tau hauj lwm nyob rau hauv cov pa-free ib puag ncig) dissimilation tsis yuav tsum tau lub dhau theem.

Cov kauj ruam kawg nyob rau hauv lub zog metabolism aerobes xaus kom tiav cov oxidation. Thaum zoo li no cleavage ntawm zib molecules nrog tsim lub zog, uas yog tej nyob rau hauv lub tsim ntawm ATP.

Nws yuav tsum tau muab sau tseg tias ATP synthesis tshwm sim nyob rau hauv tus txheej txheem ntawm ntsev thaum ADP yog txuas mus rau ib tug inorganic phosphate. Yog li adenosine triphosphate yog tsim nyob rau hauv mitochondria uas ATP synthase.

Yuav ua li cas cov tshuaj tiv thaiv yuav siv sij hawm qhov chaw thaum lub sij hawm tsim ntawm lub hwj chim kev twb kev txuas?

Adenosine thiab phosphate muab tsim ATP thiab lub zog daim ntawv cog lus, uas yog siv rau cov tsim ntawm txog 30,6 kJ / mol. ATP muab lub zog lub hlwb, vim ib tug tseem ceeb npaum li cas los ntawm yog tso tawm thaum lub sij hawm hydrolysis yog lub zog-nplua nuj ATP bonds.

Molecular tshuab, uas yog lub luag hauj lwm rau lub synthesis ntawm ATP yog hais synthase. Nws muaj ob qhov chaw. Ib tug ntawm lawv yog ib tug membrane thiab yog ib tug channel los ntawm kev uas protons poob hauv mitochondria. Thaum no lub zog yog tso tawm, uas yog kuaj los ntawm lwm tus yam ntxwv ib feem ntawm lub ATP yog hu ua F1. Nws comprises ib stator thiab ib tug rotor. Ib tug stator fixedly nyob rau hauv daim nyias nyias thiab muaj lub delta cheeb tsam, thiab kuj alpha- thiab beta-subunits, uas yog lub luag hauj lwm rau cov tshuaj synthesis ntawm ATP. Lub rotor comprises gamma thiab epsilon subunits. Qhov no yog ib feem yog spinning, siv lub zog ntawm cov proton. Qhov no yog qhia ATP synthase synthesis yog protons nrog lub txheej membrane ntawm mitochondria qhia ntawm hauv nruab nrab.

Nws yuav tsum tau muab sau tseg tias tshuaj nyob rau hauv lub cell yam ntxwv spatial ordering. Cov khoom ntawm tshuaj cov kev sib tshuam ntawm tshuaj yog faib asymmetrically (zoo them ions mus nyob rau hauv ib tug coj, thaum lub sij hawm tsis zoo them hais yuav muab xa mus rau lwm sab), ua daim nyias nyias electrochemical peev xwm. Nws muaj cov tshuaj thiab hluav taws xob Cheebtsam. Nws yuav tsum tau hais tias qhov no tej zaum nyob rau saum npoo ntawm mitochondria ua ib tug universal daim ntawv ntawm lub zog cia.

Tus qauv no nrhiav tau los ntawm lus Askiv paub txog P. Mitchell. Nws yog speculated tias lub substance tom qab lub oxidation tsis noj rau hauv daim ntawv ntawm molecules, thiab zoo thiab tsis zoo them ions, uas yog muab tso rau ob tog hauv daim nyias nyias ntawm mitochondria. Qhov no assumption yog ua tau rau yus qhov xwm ntawm qhov cov kev mus ntawm lub tsim ntawm lub zog-nplua nuj phosphate nyob rau hauv lub synthesis ntawm ATP, thiab tseem mus npaj lub hypothesis chemiosmotic tshuaj tiv thaiv no.