Plate screening methods for the detection of polysaccharase-producing microorganisms

Polysaccharide-degrading enzymes (polysaccharases) are widely applied in industry. One of the sources of these enzymes are polysaccharide-degrading microorganisms. To obtain such microorganisms from enrichment cultures, strain collections or gene libraries, efficient plate screening methods are required that discriminate between intact and degraded polysaccharide. This can be achieved by making use of specific physicochemical properties of the polysaccharide, such as complex formation with dyes and gelling capacity, or by the application of dye-labelled polysaccharides. This review presents a survey of plate methods based on these principles. Both theoretical and practical aspects of the methods are discussed.