Numfashi sarkar: aikin enzymes

All biochemical halayen a cikin sel wani kwayoyin faruwa tare da makamashi kashe kudi. Numfashi sarkar - a jerin takamaiman Tsarin cewa suna located a ciki membrane na mitochondria da kuma bauta ga samuwar ATP. Adenosine ne m tushen samar da makamashi da kuma iya tara da 80 zuwa 120 KJ.

Numfashi electron sarkar - abin da yake da shi?

Electrons da protons taka muhimmiyar rawa a samar da makamashi da ilimi. Sun haifar da wani irin ƙarfin lantarki bambanci a tarnaƙi na membrane na mitochondria cewa ya haifar da wani directed motsi daga cikin barbashi - yanzu. Numfashi sarkar (da shi da dai sauransu, electron kai sarkar) shine matsakanci a canja wuri na gaskiya caje barbashi a cikin intermembrane sarari da kuma barnatar da cajin barbashi a cikin kauri daga cikin ciki membrane na mitochondria.

Babban rawa a cikin samuwar makamashi nasa ne da ATP-synthase. Wannan hadadden sa na makamashi musanya masa a cikin shugabanci na proton motsi a cikin biochemical makamashi tsakaninsu. Af, shi ne kusan m ga hadaddun aka located a cikin chloroplast na shuke-shuke.

Kuma gidaje na numfashi sarkar enzymes

Electron canja wuri ne tare da biochemical halayen a gaban enzyme tsarin. Wadannan ilimin aiki abubuwa, mutane da yawa kofe na wanda ya samar da manyan sifofi, bauta a matsayin shamaki ba a canja wuri na electrons.

Gidaje na numfashi sarkar - suna tsakiyar gyara na sufuri da na cajin barbashi. Total a ciki mitochondrial membrane 4 ne na wannan samuwar, kazalika da ATP synthase. Duk wadannan Tsarin raba na kowa burin - Kintsa da dai sauransu electron canja wuri na hydrogen protons a intermembrane sarari kuma, kamar yadda wani sakamako, kira na ATP.

A hadaddun ne wani tari na gina jiki, tsakanin wanda akwai enzymes, tsarin da sigina sunadaran. Kowace daga cikin 4 gidaje cika ta kawai ya halayyar, aiki. Bari mu ga abin da ayyuka a cikin sauransu gabatar da wadannan sifofi.

na hadaddun

Canja wuri na electrons a cikin ciki na mitochondrial membrane babban rawa da aka buga da numfashi sarkar. Kawar dauki na hydrogen protons da electrons rakiyar su - daya daga cikin manyan halayen da dai sauransu A farko sa na kai sarkar kwakwalwa kwayoyin na nad * H + (a dabbobi), ko NADP * H + (shuke-shuke), biye da tsakiyan nonon na hudu hydrogen protons. A gaskiya, saboda wannan hadadden biochemical dauki Na kuma ake kira NADH - dehydrogenase (mai suna tsakiyar enzyme).

A abun da ke ciki dehydrogenase hadaddun baƙin ƙarfe-sulfur sunadaran hada 3 iri, da kuma flavin mononucleotide (FMN).

II hadaddun

Aikin wannan hadaddun ba ya unsa da canja wurin da hydrogen protons a intermembrane sarari. Babban aiki na wannan tsarin ne don bayar ƙarin electrons da electron kai sarkar ta wajen succinate hadawan abu da iskar shaka. Jamhuriyar enzyme hadaddun - succinate-ubiquinone oxidoreductase, wanda catalyzes da tsakiyan nonon na electrons daga succinic acid da kuma canja wuri zuwa ubiquinone ne lipophilic.

Maroki na hydrogen protons da electrons da biyu hadaddun ne ma fad * H _2. Duk da haka, flavin adenine dinucleotide ingancinsu kasa da cewa na ta analogues - nad ko NADP * H * H.

A abun da ke ciki II kunshi iri uku hadaddun baƙin ƙarfe-sulfur sunadaran da tsakiyar oxidoreductase enzyme succinate.

III hadaddun

A gaba bangaren na lissafi, da dai sauransu kunshi cytochrome b ₅₅₆ b _560, kuma c _1, kazalika da baƙin ƙarfe-sulfur gina jiki Hadarin. Aiki na uku sa ake dangantawa da canja wuri na biyu hydrogen protons a intermembrane sarari, da kuma electrons daga lipophilic ubiquinone zuwa cytochrome C.

Hadarin alama na gina jiki shi ne cewa shi dissolves a kitse. Sauran sunadarai na wannan kungiyar cewa hadu a gidaje na numfashi sarkar, ruwa mai narkewa. Wannan yanayin rinjayar da matsayi na gina jiki a cikin kauri daga cikin ciki mitochondrial membrane.

The uku sa na ayyuka kamar yadda ubiquinone-cytochrome c oxidoreductase.

hadaddun IV

Ya cytochrome-oxidant hadaddun cewa ne tashar karshe a da dai sauransu Its aiki ne don canja wurin electrons daga cytochrome c ga oxygen kwayoyin halitta. Daga bisani barnatar da cajin Yã atoms zai amsa tare da hydrogen protons ta samar da ruwa. Babban enzyme - cytochrome c oxidoreductase oxygen.

A tsarin da hudu hadaddun hada da cytochrome wani, wani _3, da kuma biyu jan kwayoyin halitta. A tsakiyar rawa a cikin canja wurin na electrons zuwa oxygen tafi cytochrome a _3. The hulda da wadannan sifofi aka mur nitrogen cyanide da carbon monoxide, a cikin duniya, ma'ana, shi take kaiwa zuwa ƙarshe na ATP kira da halaka.

ubiquinone

Ubiquinone - a bitamin-kamar abu, wani lipophilic fili, wanda motsa yardar kaina a cikin kauri daga cikin membrane. mitochondrial numfashi sarkar ba zai iya yi ba tare da wannan tsarin, watau. k. Shi ne alhakin electron kai daga gidaje I da na II su hadaddun III.

Ubiquinone ne benzoquinone wanda aka samu. Wannan tsarin iya kira a makircinsu Q harafi ko rage tsawon LN (lipophilic ubiquinone). A hadawan abu da iskar shaka daga cikin kwayoyin take kaiwa ga samuwar na semiquinone - mai karfi oxidizer, wanda shi ne yiwuwar hatsari ga cell.

ATP synthase

Babban rawa a cikin samuwar makamashi nasa ne da ATP-synthase. Wannan tsarin yana amfani da gribopodobnaya makamashi directed motsi na barbashi (protons) a maida shi cikin sinadaran makamashi.

Ainihin tsari da ya auku a ko'ina cikin da dai sauransu - shi ne hadawan abu da iskar shaka. A numfashi sarkar ne alhakin electron kai a cikin mitochondrial membrane thicker da su jari a cikin matrix. Lokaci guda, da gidaje na I, III da IV ne pumped hydrogen protons a intermembrane sarari. cajin bambanci a tarnaƙi na membrane take kaiwa zuwa directional motsi protons ta hanyar da ATP synthase. Tun H + shigar da matrix, electrons an hadu (cewa suna hade da oxygen) ta samar da wata tsaka tsaki abu don cell - ruwa.

ATP synthase F0 kunshi kuma F1 subunits wanda tare samar da na'ura mai ba da hanya tsakanin hanyoyin sadarwa kwayoyin. F1 kunshi uku uku alpha da beta subunits, wanda tare samar da wata tashar. Wannan tashar yana daidai da wannan diamita, wanda da hydrogen protons. Tare da nassi na gaskiya caje barbashi ta hanyar da ATP synthase shugaban F ₀ kwayoyin da aka juya ta 360 digiri a kusa da axis. A wannan lokaci, to HAU ko ADP (adenozinmono- da diphosphate) suna a haɗe phosphate saura tare da wani high-makamashi shaidu, wanda kewaye manyan adadin kuzari.

ATP synthase ake samu a cikin jiki, ba kawai a cikin mitochondria. A shuke-shuke, wadannan gidaje suna kuma located a kan membrane na vacuoles (tonoplast), kazalika da chloroplast thylakoids.

Har ila yau a cikin dabba Kwayoyin da shuka ATPases ne ba. Bã su da wani irin wannan tsarin a matsayin cewa na ATP synthase, amma su mataki ne directed a kan kawar da phosphate sharan da kashe kudi da makamashi.

A nazarin halittu ma'anar numfashi sarkar

Da fari dai, karshen samfurin da dai sauransu halayen ne da ake kira rayuwa ruwa (300-400 ml a kowace rana). Abu na biyu, da kira na ATP da makamashi ajiya a biochemical shaidu na kwayoyin. A ranar 40-60 kg adenosine aka hada, da kuma guda da ake amfani a enzymatic halayen Kwayoyin. A rayuwa na daya kwayoyin na ATP ne 1 minti daya, don haka da na numfashi sarkar dole ne ta yi tafiya daidai, daidai da ba tare da kurakurai. In ba haka ba, da cell zai mutu.

Mitochondria suna dauke ikon tashoshin na wani cell. Su yawan dogara a kan makamashi da cewa ana buƙatar ga takamaiman ayyuka. Alal misali, neurons za a iya kidaya har zuwa 1000 mitochondria wanda sau da yawa samar da wani tari a cikin synaptic ake kira plaque.

Bambance-bambance tsakanin numfashi sarkar in shuke-shuke da dabbobi

A shuke-shuke, an ƙarin "ikon shuke-shuke" na cell ne a chloroplast. A ciki membrane daga cikinsu kuma sami ATP synthase, kuma wannan shi ne wani amfani a kan dabba Kwayoyin.

Har ila yau, shuke-shuke iya tsira a high yawa na carbon monoxide, nitrogen da cyanide saboda cyanide-resistant hanya a da dai sauransu Numfashi sarkar haka ƙare a ubiquinone, daga abin da electrons aka kai tsaye canjawa wuri zuwa oxygen kwayoyin halitta. A sakamakon haka, kasa ATP da aka hada, duk da haka, da shuka zai iya tsira m yanayi. Animals a irin haka ne, da shafe tsawon daukan hotuna zuwa mutu.

Za mu iya kwatanta yadda ya dace da nad, fad da cyanide-resistant hanya ta cikin ATP nuna alama samuwar lokacin da canja wurin 1 electron.

• tare da nad ko NADP kafa ta 3 kwayoyin na ATP.
• Fad an kafa tare da biyu kwayoyin na ATP.
• na cyanide suranta 1] orewar hanya ATP kwayoyin.

Evolutionary muhimmancin da dai sauransu

Domin duk eukaryotic kwayoyin, manyan tushen samar da makamashi ne na numfashi sarkar. Biochemistry ATP kira a cikin cell ne zuwa kashi biyu iri daban-daban, substrate phosphorylation da oxidative phosphorylation. Da dai sauransu da ake amfani a cikin kira na biyu da irin makamashi, watau. E. Saboda redox halayen.

A prokaryotic kwayoyin ATP kafa kawai a substrate phosphorylation a glycolysis mataki. Shida-carbon sugars (zai fi dacewa glucose) da hannu a dauki sake zagayowar, da kuma fitarwa cell na'am biyu kwayoyin na ATP. Wannan irin makamashi aka dauke su mafi m kira, watau. K. Eukaryotes a lokacin oxidative phosphorylation kafa 36 ATP kwayoyin.

Duk da haka, wannan ba ya nufin cewa yau shuke-shuke da dabbobi sun rasa ikon substrate phosphorylation. Kamar irin wannan ATP kira shi ne kawai daya daga cikin matakai uku na samar da makamashi a cikin cell.

Glycolysis a eukaryotes faruwa a cytoplasm na cell. Akwai dukan zama dole enzymes cewa zai iya manne glucose zuwa biyu kwayoyin na pyruvic acid don ya samar 2 kwayoyin na ATP. All m matakai dauki wuri a cikin mitochondrial matrix. Krebs sake zagayowar ko tricarboxylic acid sake zagayowar, kamar yadda yakan faru a cikin mitochondria. Wannan rufe sarkar halayen a sakamakon wanda haduwa nad kuma fad * H * H2. Wadannan kwayoyin Za a yi amfani a matsayin consumable a da dai sauransu