Template:SUIT-006 O2 mt D022

Steps and respiratory states

Step	State	Pathway	Q-junction	Comment - Events (E) and Marks (M)
1SRot	S_L	S	CII	1SRot Succinate, S ( type S-pathway to Q). Succinate pathway control state (S-pathway) after inhibiting CI with rotenone, which also inhibits the F-pathway. Non-phosphorylating resting state (LEAK state); LEAK respiration L(n) in the absence of ADP, ATP, AMP (no adenylates).
2D	S_P	S	CII	1SRot;2D Succinate, S ( type S-pathway to Q). OXPHOS capacity P (with saturating [ADP]), active OXPHOS state.
2c	Sc_P	S	CII	1SRot;2D;2c Succinate, S ( type S-pathway to Q). OXPHOS capacity P (with saturating [ADP]), active OXPHOS state. Addition of cytochrome c yields a test for integrity of the mtOM (cytochrome c control efficiency). Stimulation by added cytochrome c would indicate an injury of the mtOM and limitation of respiration in the preceding state without added c due to loss of cytochrome c. Typically, cytochrome c is added immediately after the earliest ADP-activation step (OXPHOS capacity P with saturating [ADP]).
3U	S_E	S	CII	1SRot;2D;2c;3U Succinate, S ( type S-pathway to Q). Uncoupler titration (avoiding inhibition by high uncoupler concentrations) to obtain electron transfer (ET) capacity E (noncoupled ET-state). Test for limitation of OXPHOS capacity P by the phosphorylation system (ANT, ATP synthase, phosphate transporter) relative to ET capacity E in mt-preparations: E-P control efficiency and E-L coupling efficiency. In living cells: E-R control efficiency and E-L coupling efficiency.
4Ama	ROX			1SRot;2D;2c;3U;4Ama Rox is the residual oxygen consumption in the ROX state, due to oxidative side reactions, estimated after addition of antimycin A (inhibitor of CIII). Rox is subtracted from oxygen flux as a baseline for all respiratory states, to obtain mitochondrial respiration (mt).