'pH' in a small volume?

Peter Lundberg peterl at umdix.umdc.umu.se
Thu Sep 22 04:39:03 EST 1994

Dear Bill,

* So the pH inside the small volume should be viewed as a
'time-average' then. This time-average is different in different
locations inside the volume? It would be very interesting to obtain a
'map' of this 'time-averaged' pH, near proteins (say hemoglobin in an
erythrocyte), near the cell membrane, etc.

* This averaging I can sort of understand, but what about the transport
of protons across a cellular membrane? How does that affect the
picture? This transport is often viewed as a stoichiometric transport
of so and so many protons (or ions) being translocated in each cycle.
My view was that this transport is a lot slower than any
'time-averaging' of the pH inside the small volume. Thus, the incoming
protons would 'suddenly' change the pH inside the volume?

* I guess my question really is: What are the relative time-scales of
proton transport processes (across biological membranes), compared with
biochemical events (enzymatic reactions or other)! 



Peter Lundberg
Email: peterl at umdix.umdc.umu.se

More information about the Bioforum mailing list