(no subject)

[Haralt Leiter]

Hi everybody !

I´m a poor PhD Student (my supervisor hasn´t paid me) purifying a
fucosyltransferase with an estimated (SDS-PAGE) molecular weight of at
least 50kDa. During ultrafiltration the entire enzyme-activity passes
through the membrane (cutoff 30000). Has anybody observed a similar
effect or can offer a reasonable explanation ?
I use a 25mM Tris/HCl pH7,3
	0,1% Triton X-100
	10% Glycerol
	0,02% NaN3    buffer and the applied protein solution contains several
hundreds of micograms.
Thanks for any answers in advance

Haralt

BTW, I have already tried membranes of different companies