Map · Energy metabolism · Oxidative phosphorylation

Oxidative phosphorylation electron transport chain · Complex I–V

Inner mitochondrial membrane. Four real crystals in electron-flow teaching order. The map page (etc.html) has no chemistry — open a complex. Complex II opens TCA step 6.

Oxidative Phosphorylation — the Electron Transport Chain (Complex I–V)

OXPHOS · MAP

Electron Transport Chain (legend — not a respirasome)

NADH + O₂ + ADP + Pᵢ → NAD⁺ + H₂O + ATP

Four real crystals in electron-flow teaching order. No chemistry on this page — open a complex below, or click a tube on the map. Complex II is not a fifth mesh: it is TCA Step 6 (SDH), the same page as the II door.

PDB 4HEA · 1BGY · 1OCC · 1BMF · CII = 1ZOY

▶ OPEN MAP
I

Complex I NADH:ubiquinone

NADH → Q

FMN + Fe-S wire. 4HEA.

EC 7.1.1.2

▶ OPEN
II = TCA 6

Complex II SDH — same page

succinate → Q

Not a second simulator. Opens TCA Step 6.

EC 1.3.5.1 · 1ZOY

▶ OPEN
III

Complex III cytochrome bc₁

QH₂ → cyt c

Q-cycle half. 1BGY.

EC 7.1.1.8

▶ OPEN
IV

Complex IV cyt c oxidase

cyt c → O₂

O–O cleavage. 1OCC.

EC 7.1.1.9

▶ OPEN
V

Complex V ATP synthase F₁

ADP + Pᵢ → ATP

Binding-change. 1BMF.

EC 7.1.2.2

▶ OPEN
⤷ Per NADH ≈ 2.5 ATP · per FADH₂ ≈ 1.5 ATP (chemiosmotic theory, Mitchell 1961). Complex II = TCA 6 sdh.html — one URL, two doors.