We have constucted and apparently expresssed a fusion protein
with GST at the end terminus and a yeast ORF of unknown function at the
C terminus. After induction, we can detect a fusion protein of the
right size using polyclonal anti-GST anti-body. The size of the fusion
protein is 60-70kDa. However, following standard protocols we cannot
get the protein to stick to Glutathione Sepharose.
1. Is there something in yeast extracts which interferes with
binding? Are there alternate protocols ?