Question

A) How many protons are required for ATP synthase to rotate 360 degrees? Explain!

B) How many ATPs are produced in a 360-degree rotation of ATP synthase? Explain!

C) How does this account for the fact that electrons from 2 NADH molecules results in the production of 5 ATP molecules? Explain!

Answer 1

A)

• there are 10 subunits in the c ring of ATP synthase
• Every subunit releases 1 proton into the matrix when it turns 360 degree
• Hence totally 10 protons are released into the matrix by 10 subunits for every 360 degree turn

B)

• Every 120 degree catalyses the formation of 1ATP
• Every 1 degree catalyses the formation of 1/120 ATP
• Every 360 degree catalyses the formation of 1/120 X360 ATP=3ATP
• Therefore total 3 ATPs are produced

C)

• Each NADH2 yields 2.5 ATP
• Therefore 2 NADH2 yields 2.5 X2= 5 ATP