ATP synthase

Question 1

where are ATP synthases located in mitochondria

Answer 1

in criastae in the innner mmebrane
cells that have high metabolic activity have more criastae

Question 2

where and why are H pumped in mitochondria

Answer 2

pumped across the innner membrane resulting in proton motive formce

pumped from the intermembrane space to the matrix

Question 3

what are the two distinct compoents fo ATP synthase

Answer 3

F1- and Fo

Question 4

F1-

Answer 4

peripheral membrane protein that catalzyes the hydrolysis of ATP when in reverse and ATP production when functioning normally

Question 5

Fo

Answer 5

integral membrane protein with a proton pore
contains the part that moves and movemnt of protons

Question 6

immobilized part of ATP synthase

Answer 6

alternating aB sunbunints anchored to a by b proteins

Question 7

c ring in ATP synthase

Answer 7

can rotate- rotaional catalasys
connected to F1 by y protein

Question 8

protein in membrane in ATP synthase

Answer 8

has half channel where h can go halfway through

two half channes stop and connect in the c ring

Question 9

function of Fo in ATP synthase

Answer 9

proton transport DOWN concentration gradient- passsive- more like a channel

Question 10

c protein in ATP synthase and the amino acids and their charges

Answer 10

unprotonated glutamate (aspartate in bacteria) has negatvie charge

balanced by positive charge on arginine in the a subunit

Question 11

what allows the proton to enter the c subunit in ATP synthase

Answer 11

glutamate/ aspartate

Question 12

what “boots” the proton out

Answer 12

arginine subunit with positive charge

Question 13

step 1 in proton movement in ATP synthase

Answer 13

proton from intermembrane space enters the first half channel and moves towards the empty unprotonated glutamate proton binding site

Question 14

what happens after proton binds to glutamate

Answer 14

proton binding displaces positively charged Arg-210 side chain on the a subunit which swings over to the filled proton binding site on the adjacing c subunit displacing/ booting the bound proton

Question 15

what happnes after the bound proton is booted by argiine

Answer 15

the displaced adjacent proton moves throug the second half channle and is releaed into the matrix leaving an empty proton binding site in glu-61

Question 16

what happens after the proton is released into the matric

Answer 16

the c ring rotates counterclockwise to move the empty c subunit over halfchannel 1
-slight conformational change when h binds shifting c protiein away from h channel
transient protonation in each c subunit drives rotation and transports protons

Question 17

movement in f type pumps

Answer 17

continuous rotation of c ring and entry of H+

Question 18

what rorates in F type pumps

Answer 18

Y shaft but aB are anchohred which leads to the Y shaft producing conformational change in aB subunits as it turns but the changes arent unifrom resulting in 3 states

Question 19

B subunit confromations

Answer 19

each subunit can assume 3 different confromations
each has one catalytic site for ATP sytnehis

B-ATP—– tight
B-ADP—–loose
B-empty

Question 20

O state

Answer 20

B empty- weak binding of ATP so ATP is released

Question 21

L state

Answer 21

B-ADP—- loose
binds AP and Pi more strongly

Question 22

T state

Answer 22

B-ATP—- tight

binds ADP and Pi so tightly that they are joined to form ATP