I have been attempting obtain whole-cell protein profiles of the oral
anaerobe Porphyromonas gingivalis using two-dimensional electrophoresis,
basically according to the method of O'Farrell (1975). I get clear bands in
the first dimension (isoelectric focussing in tube gels) but these proteins
fail to transfer into the second dimension slab gel. I have varied the
concentration of SDS, pH and incubation time in the second dimension buffer,
and ensured good contact between the two gels. None of these variables
produce an improvement.
2D electrophoresis is not known for being straightforward, but does anyone
have any experience of these problems and any suggestions for improving my
results?
