[HTML][HTML] Changing residue 338 in human factor IX from arginine to alanine causes an increase in catalytic activity

J Chang, J Jin, P Lollar, W Bode, H Brandstetter… - Journal of Biological …, 1998 - ASBMB
This study was designed to identify functionally important factor IX (FIX) residues. Using
recombinant techniques and cell culture, we produced a mutant FIX with arginine at 338
changed to alanine (R338A-FIX). This molecule had approximately 3 times greater clotting
activity than that of wild type FIX (wt-FIX) in the activated partial thromboplastin assay.
R338A-FIX reacted normally with a panel of three FIX specific monoclonal antibodies and
migrated on sodium dodecyl sulfate-polyacrylamide gels indistinguishably from wt-FIX …