Detection of gelatinolytic enzyme activities after sodium dodecyl sulfate-electrophoresis and protein blotting.

Visualization of proteases with gelatinolytic activity in sodium dodecyl sulfate gels is described. After conventional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, proteins are transferred onto nitrocellulose membranes preincubated with 0.3% gelatine. During the protein electrotransfer, the proteases are renaturated and their enzymatic activity is restored. After nonspecific protein staining, bands with proteolytic activity appear as white areas on a dark background.