In article <2v0cm1$mh7 at styx.uwa.edu.au> camn at uniwa.uwa.edu.au (Cameron Neylon) writes:
>Ok, having read Dr Kell's comments and now having read most of the
>references (I can't seem to get the Bacterial Energy Transduction ref) I
>have a few questions;
>>My project involves the measuring of oxygen consumption and lactate
>production in a cell suspension to estimate total ATP production.
>The work I quoted in my last post (Brand,et al (1993) Biochem. J.
>291:739-748) and other communications between our lab and the Brand lab
>have implied that this approach is at best approximate and at worst,
>completely wrong.
I didn't see your last post (possible news outage here; not uncommon) but I would
agree with Martin Brand that the method is at best approximate in intact cells.
>>Does Dr Kell's hypothesis render Brands work irrelevant in the
>determining of ATP production from O2 consumption (by making the proton
>leak, if it is there, an unimportant issue) or does it only make things
>worse for those of us trying to determine ATP production from O2
>consumption.
The question of where protons go in the ABSENCE of valinomycin, thiocyanate
and so on is orthogonal to the question of the number that are actually pumped
across the midpoint of membrane (regardless of how they would normally
return to where they came from).
>>Or to put it differently. Is there any hope of an exact and constant
>stoichiometry between electrons transported (or at least FADH2 and NADH
>oxidised) and ATP produced.
Hope is unimportant. Likelihood is zero. Think about what uncouplers do (ET up,
or at least not down, ATP down).
>ANd if there is a constant stoichiometry
>does anybody know what it is, or how it could be measured in a given
>system (easily).
>>Or am I really completey without hope in this respect? Please help :-)
>>----
>>Cameron Neylon, Honours, Dept of Biochemistry,
>University of Western Australia
>>(09) 368-2717 or more regularly camn at uniwa.uwa.edu.au>>Biochemistry: noun, The art of sitting, late at night, transferring
> ridiculously small volumes of liquid with one hand and
> attempting to hold onto one's sanity with the other.
>Internet: noun, The art of sitting, late at night, transferring
ridiculously large numbers of bytes with one hand and
attempting to hold onto one's sanity with the other.
Best wishes,
Douglas.
