help X-gal

[R. Rex Denton]

 There were two recent articles in Biotechniques (sorry, issues not handy)
> about using X-gal in a mixture of water and DMSO.  Rationale was substitute
> for 'hazardous' DMF.  Looked reasonable to me, but I recall putting X-gal
> in 100% DMSO once and over several days, a faint blue color appeared (even
> though the solution was frozen in the refrigerator.  Still, you may be able
> to salvage your solution via the Biotechniques procedures.  SWM
> 
> mamber at synapse.bms.com


Would not recommend this DMSO/X-Gal solubilization thing.  Tried it and found
reduced cloning efficiency (reduced colony numbers) with DMSO.  Hanahan
mentions that oxidation products of DMSO influence transfection efficiencies
but I suspect they may also be toxic to the rescued transformants.  Just my two
cents worth...