Nov 9, 2013
2
0
San Diego, CA
Status
Pre-Medical
Question: Is the catalytic knob subunit of ATP synthase hydrophobic or hydrophilic? What about the rotor subunit? Explain your reasoning.

I'm working on the chemiosmosis and happen to come across this question. My answer for it is that the catalytic knob subunit is hydrophilic since it's on the matrix side of the mitochondrial inner membrane, whereas the rotor subunit hydrophobic since it's embedded within the membrane.

Please correct me if I'm wrong. I've attached here a picture of the ATP synthase structure for your convenience. The catalytic knob subunit is labeled 4, and the rotor subunit 2.

Thank you in advance for any helps! :)

 

PlumbLine

5+ Year Member
May 23, 2012
244
53
Status
Medical Student
That logic is the same approach that I would use. Inside the bilayer = hydrophobic. Outside = hydrophilic