Hi all,
I'm presently using the his-tag sequence from Novogen's pET19b which
has 12 histidines(10 in tandem), 4 aspartates(enterokinase cleavage site), 2
glycines, 2 serines, a methionine, a lysine and an isoleucine residue in the
sequence upstream of my own protein but I'm not using the pET19b vector but
cloned the fusion sequence into another vector which uses the lac p/o control.
What I'm observing is this tag is making a vast difference to the
folding/assembly characteristics of some of my mutant fusions, namely, the
presence of the tag greatly facilitates assembly of my mutant proteins. I'm
observing this phenomena in both E. coli and T.ni insect cells. Has anyone
any information or ideas on how this tag may be influencing the favourable
folding of my mutant proteins or is there anything in the literature along
these lines. Any comment would be greatly appreciated. Thanks!