[RASMB] Protein degradation in AUC

[Leech, AP]

Hi Claus, all,

I have given up with pipe-cleaners as they usually have a wire down the
middle which risks scratching. I now use Chemtronics #140 Foamtips which
are small enough to fit into the sectors but all plastic construction.
These seem to be good for removing mechanically adherent residues that
liquid reagents don't dissolve.

I usually keep the residue from sample loading in the lab at about the
same temperature as the run, so if necessary the user can run a
comparison gel after the experiment - sometimes the protease is in the
sample before it gets to the cell, and the time at 20C is the problem!

Andrew

Claus Urbanke wrote:
> Hello RASMBers,
> 
> for a few weeks now we encounter a nasty problem regarding the cleaning 
> of epon centerpieces (charcoal/aluminum). With an occurence of 10 - 30% 
> protein will be partially cleaved (by a protease?) after a sedimentation 
> run. Has anyone encountered this before? How can one clean the 
> centerpieces. The resistance chart tells me that GuaHCl is satisfactory 
> and urea is unknown, so we are testing some centerpiece fragments over 
> the weekend in concentrated urea solution.
> 
> We are cleaning our centerpieces with a pipe cleaner using commercial 
> household detergent rinse them with hot water and finally with doubly 
> distilled (dd) water. The detergent itself was tested to be protease 
> free. We use saphire windows that are cleaned by >  1 hour 50% nitric 
> acid, rinsing with water, dd water and drying.
> 
> Many thanks in advance for any suggestion
> 
> Claus
> 
> 
> 

-- 
Dr Andrew Leech                   *  Laboratory Manager
Technology Facility               *  Molecular Interactions Laboratory
Department of Biology (Area 15)   *  Tel   : +44 (0)1904 328723
University of York                *  Fax   : +44 (0)1904 328804
PO Box 373,  York  YO10 5YW       *  Email : apl3 at york.ac.uk