Can MBP fusions be digested with factor Xa while bound to the amylose resin?
Cutting a bound fusion with factor Xa has been done, by us and in Rawlings and Kaslow, 1992, J Biol Chem 267(6)3976-82. It has two problems that make it less than ideal. First, it takes a lot more factor Xa. With the fusion immobilized, it takes 5% for 24-48h to get decent cleavage. The second problem is that during the incubation, a little of the MBP always seems to fall off the column. This may be because there are trace amounts of amylase bound to the column too, and the amylase liberates enough maltose over time to elute some of the MBP.
