2. Electrons collected in nadh and FADH are released and transported to O, via the respiratory chain The chain is located on the convoluted inner D membrane(cristae) of mitochondria in eukaryotic cells(revealed by Eugene Kennedy and Albert Lehninger in 1948)or on the plasma membrane in prokaryotic cells A 1.14-volt potential difference(E )between NADH (-0.320 V)and O2(0.816 V)drives electron flow through the chain. D
2. Electrons collected in NADH and FADH2 are released and transported to O2 via the respiratory chain • The chain is located on the convoluted inner membrane (cristae) of mitochondria in eukaryotic cells (revealed by Eugene Kennedy and Albert Lehninger in 1948) or on the plasma membrane in prokaryotic cells. • A 1.14-volt potential difference (E`0 ) between NADH (-0.320 V) and O2 (0.816 V) drives electron flow through the chain
The respiratory chain consists of four large multi protein complexes(, Il, III, and IV; three being proton pumps) and two mobile electron carriers ubiquinone( q or coenzyme Q, and cytochrome c Prosthetic groups acting in the proteins of respiratory chain include flavins(FMn, FAD) hemes(heme A, iron protoporphyrin IX, heme C) iron-sulfur clusters(2Fe-2S, 4Fe-4S), and copper
• The respiratory chain consists of four large multiprotein complexes (I, II, III, and IV; three being proton pumps) and two mobile electron carriers, ubiquinone (Q or coenzyme Q, and cytochrome c. • Prosthetic groups acting in the proteins of respiratory chain include flavins (FMN, FAD), hemes (heme A, iron protoporphyrin IX, heme C), iron-sulfur clusters (2Fe-2S, 4Fe-4S), and copper
ATP synthase Outer membrane (F。F1) Freely permeable to Cristae Inner membrane Impermeable to most small molecules and ions luding H I .Respiratory electron carriers( Complexes I-IV · ADP-ATP translocases ATP synthase(FFu) her me transpo Matrix Pyruvate dehydrog Cristae(the convoluted Citric acid cycle enzymes inner membrane of Fatty acid B-oxidation mitochondria) is Amino acid oxidation where the respiratory Ribo DNA, ribosome Porin channels Many other enzymes ATP, ADP, Pi, Mg2+, Ca2,K. chain is located Many soluble metabolic intermediates
Cristae (the convoluted inner membrane of mitochondria) is where the respiratory chain is located
NADH NAD+H NADH-CoO reductase Succinate. Co0 complex reductase complex Fumarate FMN H·out FAD FAD.+2 H CoQH2-Cytochrome c Cyt b reductase complex Hout Fe-S : 200- Four multi-protein 三兰 Complexes(LIl so IlL, and Tv) Cytochrome c oxIdase com Cyt a TTwo mobile yt a3 Electron carriers 202+2H H,O
Four multi-protein Complexes (I, II, III, and IV) Two mobile Electron carriers I II III IV
H,C HC H,C C=0 HC H CH2 H2 H-C-OH H-C-OH H-C-OH H-C-OH CH, OPO, 2 CH, OPO, CH- OPO, 2- Flavin mononucleotide Semiquinone intermediate Reduced flavin mononucleotide (FMN) (FMNH2) FMN can accept one electron (and FMNH, can donate one electron) to form a semiquinone radical intermediate
FMN can accept one electron ( and FMNH2 can donate one electron) to form a semiquinone radical intermediate