Figure 1

Figure 1

Fluorescent BEL β-trefoil purification. (A) Elution profile of fluorescent BEL β-trefoil on the IMAC column. The blue line refers to the protein elution followed spectrophotometrically at 280 nm; the green line represents the increase in the imidazole concentration along the gradient. (B) Elution profile of fluorescent BEL β-trefoil on the G75 gel filtration column, recorded at 280 nm. (C) SDS-PAGE (12%). Lane 1: molecular mass markers (BlueRay Prestained Protein Marker, Jena Bioscience); lane 2: crude extract from bacteria; lane 3: first peak from the IMAC column, corresponding to nonspecific proteins; lane 4: second peak from the IMAC column, corresponding to the fluorescent BEL β-trefoil; lane 5: pure fluorescent BEL β-trefoil present in the main peak of the G75 chromatography.