The problem is that the activity is all in the P1 (pellet after homogenization and centrifugation at 1,000xg). When we apply the re-suspended P1 to a sucrose step gradient all the activity is at the 20/30% sucrose interface. This interface material is rather gelatinous and can be lifted out pretty much intact with a spatula. Thus, further enrichment is impossible. Does anyone know what this material is or how we might prevent it or solubilize it without detergents. We have tried DNAse, RNAse, and sonication with no change in the interface. Our activity is too labile after detergent extraction.