The specific CrSGD-mediated deglucosylation activates strictosidine and induces in vitro cross-linking and precipitation of BSA. (a) Picture of microtubes showing the apparition of a yellowish precipitate within few seconds when CrSGD was mixed with 10 mM strictosidine, its specific substrate. (b) EMSA (SDS-PAGE and Coomassie blue staining) of supernatants showing that in the specific presence of both strictosidine and CrSGD the BSA was cross-linked and precipitated and therefore barely entered the gel with a consecutive disappearance of the monomeric BSA band at 66 kDa. Cross-linking of BSA with glutaraldehyde is also shown as a control. (c) HPLC monitoring of the final strictosidine concentration (mM) in the supernatants allowed to check the specificity of strictosidine deglucosylation by recombinant CrSGD. ND, not determined.