I am puzzeled with H+ ions!

[Maria87]

Hi there,

ok, so there are loads of transporters in the cell membrane that extrude/import H+. E.g, Na+/H+ antiporter, Lactate/H+ symport, HCO3/Cl , ..... etc

ok thats fine, but when you are modeling a cell in a test tube with no vasculature, where do you expect the extracellular H+ to go? Would it degrade? or used up in celluar metabolism,....cell movement,...??

Apart from buffering and exchangers, what are the fates of intr/extra Hydrogen ions.

Many thanks
Maria

[Alysha]

I imagine the solvent you'd be using would take them up, forming hydrogen bonds... but perhaps that's the same thing that you meant by buffering?

[Alysha]

Oh, and of course, as you've seen, particularly violent chemical reactions give of little bubbles, of e.g. hydrogen gas.

[Pammy]

Actually, you definitely would not use a solvent, you'd use an aqueous buffer, which would buffer the H+. The amounts of H+ moved across the membrane are quite small (so can be buffered well), with the exception of cells such as in the gastric mucosa that pump out H+ (where the concentration gradient may be a million).
Also, the only way to generate hydrogen would be if the cells are bacteria - some of these generate hydrogen as a byproduct of their metabolism (e.g. the ones in your gut...). Else I have no idea what "vigorous reactions" you could be talking about taking place in a suspension of cells in a test tube!

[Alysha]

I guess my answer was more out of a gen chem / organic chem point of view - not really biochem, so mhmmm, I'd probably go with what Pammy said. I think i was just spurting out ideas for what can happen to hydrogen ions in general in any chemical reaction...

[Arch_Angel]

Also, your language may be showing that you're a little unsure of the nature of ions/atoms. Atoms degrading works on a quantum level and does not involve electrons, which is the component that you are working on in chemistry/biochemistry. As far as a chemist is concenred atoms do not degrade, nor can they be destroyed in any way, but molecules can be used/changed to yield energy (work) but always result in the same number of atoms at the end (although the molecule may be split or components attached to something else).