Zymographic analyses of carboxymethylcellulases secreted by the bacterium from wood-boring marine shipworms

Abstract

Zymographic techniques were used for identifying multiple carboxymethylcellulase (CMCase) activities present in the cell free culture broth of the marine shipworm bacterium. CMCase activity was associated with at least three major and four minor polypeptides. After sodium dodecyl sulphate (SDS) removal from polyacrylamide gels, the major CMCase polypeptides became active, apparently renaturing, even when samples were boiled for 10 minutes in the presence of SDS and β-mercaptoethanol (βME) prior to electrophoresis. The relative binding affinity of the active polypeptides for microcrystalline cellulose was also qualitatively determined by zymography.