Arrestin binds tightly to rhodopsin only when rhodopsin kinase has phosphorylated a sufficient number of C-terminal serines and threonines.

TLS Online TPP Program

#Id: 3347

#Unit 6. System Physiology – Plant

Arg residue swings aside, forming an interaction with the Asp on the adjacent c subunit in the ring and displacing the proton from that Asp; this adjacent proton exits through the second half- channel to the N side, completing the movement of one proton equivalent from outside to inside the matrix.

TLS Online TPP Program

#Id: 3351

#Unit 6. System Physiology – Plant

The streaming of protons through the F_o pore causes the cylinder of c subunits and the attached ϒ subunit to rotate about the long axis of ϒ, passes through the center of the α₃β₃ spheroid

TLS Online TPP Program

#Id: 3353

#Unit 6. System Physiology – Plant

Each rotation of 120 ^o , ϒ comes into contact with a different β subunit, and the contact forces that β subunit into the β-empty conformation.

TLS Online TPP Program

#Id: 3355

#Unit 6. System Physiology – Plant

If 10 protons are pumped out per NADH and 4 must flow in to produce 1 ATP, the proton-based P/O ratio is 2.5 for NADH as the electron donor and 1.5 (6/4) for succinate.

TLS Online TPP Program

#Id: 3356

#Unit 6. System Physiology – Plant

the energy of substrate oxidation (succinate yields fumarate) drives ATP synthesis in mitochondria, we would expect inhibitors of the passage of electrons to O2 (such as cyanide, carbon monoxide, and antimycin A) to block ATP synthesis.

TLS Online TPP Program

#Id: 3357

#Unit 6. System Physiology – Plant

Oligomycin and Venturicidin, toxic antibiotics that bind to the ATP synthase are potent inhibitors of both ATP synthesis and the transfer of electrons through the chain of carriers to O2.