sentence: Different strategies were used to identify these proteins as Cry1A ‐ binding proteins , for instance , several APN molecules have been shown to bind with different Cry toxins by using pull ‐ down Cry1A ‐ affinity chromatography assays followed by elution with different buffers : APN1 from Heliothis virescens was eluted with N ‐ acetyl ‐ galactosamine ( GalNAc ) containing buffer as Cry1Ac binding to APN1 relies on GalNac moieties ( Luo et al. 1997 ) ; in the case of APN2 from Manduca sexta , it was eluted using a high ‐ pH carbonate buffer ( Denolf et al. 1997 ) , while APN4 from H. virescens was eluted with 2.0 mol / L NaSCN buffer ( Banks et al. 2001 ) .