8 Responses to “F-ATP Synthase mechanism teaches scientists how to dance”

1. kallikak Says:
   January 2nd, 2007 at 8:16 pm

   I guess you have to sort of on the inside to understand the relevance of the 'dance.'

   The asymmetric gamma subunit rotates within the alpha-beta hexamer, as it does, it induces conformational changes in the beta subunit that combines ADP + Pi –> ATP. The person in the center represents the asymmetric gamma subunit, the three on the outside represent beta subunits. I would imagine they left out the alpha subunits as they are not considered catalytic, even though several residues associated with the alpha subunit do play a role in catalysis at the active site.

   Pretty cool… in a weird, twisted, and nerdy kind of way. Nice find… any explanation at the source site?

Comment by kallikak — January 2, 2007 @ 8:16 pm

2. Guts Says:
   January 2nd, 2007 at 10:38 pm

   This is on the CD that comes with the textbook Molecular Biology of the Cell, along with other neat animations, like this one:

   ATP synthase requires various modes of interaction in order to function correctly. The F1FO ATPase is composed of two rotary motors (F1 and Fo) working against each other. Thus the interactions can be classified as within each motor and between the two motors. In F1, there are interactions between the rotary part (gamma/epsilon) and the stationary part (alpha, beta) that play important roles in regulating and guiding coupling between ATP synthesis and rotation, and you can see the F1 "dance" in this animation as well.

Comment by Guts — January 2, 2007 @ 10:38 pm

3. Mesk Says:
   January 2nd, 2007 at 11:02 pm

   This hilarious video provides a more elaborate example of using dance to explain molecular biology, by building a ribosome out of hippies.

Comment by Mesk — January 2, 2007 @ 11:02 pm

4. kallikak Says:
   January 3rd, 2007 at 12:09 am

   Hi Guts

   The F1FO ATPase is composed of two rotary motors (F1 and Fo) working against each other. Thus the interactions can be classified as within each motor and between the two motors. In F1, there are interactions between the rotary part (gamma/epsilon) and the stationary part (alpha, beta) that play important roles in regulating and guiding coupling between ATP synthesis and rotation

   I think a more correct description is that the F1Fo ATP Synthase is a rotary motor comprised of two competing portions. A stator… composed of at least the alpha-beta hexamer, and the b and delta subunits. And a rotor, which consists of the c ring… 10-14 subunits, and the gamma epsilon complex.

   There are not two motors per se. The motor can be driven both forwards and backwards by ion-motive force or via ATP hydrolysis, but it is essentially the same motor. In the former case, ion diffusion through the c ring results in rotation of the c-ring gamma complex, in the latter, ATP hydrolysis drives conformational change in the beta subunits, which subsequently drives gamma rotation.

   The molecular interactions that facilitate this are fascinating…. they've been compared to the workings of clock… Walker who won the shared a Nobel for work on this on enzyme first postulated the 'escapement mechanism' in this enzyme… great stuff indeed.

Comment by kallikak — January 3, 2007 @ 12:09 am

5. Guts Says:
   January 3rd, 2007 at 6:37 am

   Just a quibble, even in your articulate descriptions, I see two motors. The gamma/epsilon subunits of F1 interact with (are connected to) the c subunit of the Fo motor. These subunits move together approximately as a rigid body. In the ATP synthesis mode, rotation of the c subunit drives the gamma/epsilon shaft (i.e. Fo acts as the motor). In the ATP hydrolysis mode rotation of the gamma/epsilon drives c subunit rotation (F1 acts as the motor). Also, the ab2 subunit of Fo interacts with the alpha3beta3 complex of F1 through the delta subunit to form the "stationary" part of the F1Fo complex (actually, these structures counter-rotate). The b2 subunits have long, elastically flexible coiled-coil structures that scientists suggest help smooth torque transmission between the two motors. Here's a good discussion ATP synthase: two motors, two fuels

Comment by Guts — January 3, 2007 @ 6:37 am

6. Guts Says:
   January 3rd, 2007 at 8:31 am

   Mesk:

   This hilarious video provides a more elaborate example of using dance to explain molecular biology, by building a ribosome out of hippies.

   lmao , I kept expecting a quick zooming in and out of Jim Morrison's face somewhere in there.

Comment by Guts — January 3, 2007 @ 8:31 am

7. kallikak Says:
   January 3rd, 2007 at 10:10 am

   Hi Guts,

   Yes, I suppose it is just a quibble, and certainly nothing to fight about. The Oster and Wang paper is a classic… I've probably read that paper 150 times… lots of great stuff in there.

   Gamma-epsilon rotation during hydrolysis mode is actually driven by the beta subunits. ATP hydrolysis in the catalytic site results in large scale conformational changes including movement of the 'catch loop' residues, and movement of the hinged DELSEED region located a considerable distance from the active site. What you have is essentially the same exact mechanism running in reverse. It is an interesting thing however that the motor can use either fuel though. I can't remember off the top of my head… but I'm pretty sure that [i]in vivo[/i] not all ATP synthase complexes are capable of proton pumping though… In any case, all isolated F1 sectors are capable of ATP hydrolysis.

   Another interesting point about ATP Synthases… the CF1CFO complex present in chloroplasts actually contains on 'off' switch that is regulated by redox potential in the chloroplasts.

   No offense intended… just a slight difference of scientific opinion.

Comment by kallikak — January 3, 2007 @ 10:10 am

8. Exile From Groggs Says:
   January 3rd, 2007 at 4:26 pm

   Did they say molecular machine? Is that allowed?

Comment by Exile From Groggs — January 3, 2007 @ 4:26 pm