how to maintain ionic strength?

[Dr Engelbert Buxbaum]

DK wrote:


> I know, sounds like a lot of work :-) But If I were a reviewer, I would 
> never buy a conclusion based on just NaCl replacement at just one 
> concentration.

Full Ack. Especially Na has considerable effects on many proteins. If
one is dealing with cytosolic proteins, the use of K is better anyway,
since the cytoplasm is a High K, low Na environment. Note that Rb, Cs
and Tl have K-like properties, Li somewhat Mg-like.

It is probably even worthwhile to try some uncharged molecules as well
(glycerol, sucrose, mannitol or the like) since any solute competes with
proteins for water, which enzymes need as a "greese" for conformational
changes during turnover. Thus solutes stabilise proteins (the named ones
are often used for that very purpose), but reduce turnover rate.