Method for the rapid screening of cellulolytic streptomycetes and their mutants

A method for the rapid screening of cellulolytic streptomycetes and their mutants is reported. The technique consists of a plate assay on media containing filter paper fibres as cellulose substrate. The cellulolytic activity is detected and measured by the formation of clearing zones around the streptomycete colonies. The sensitivity of the method is increased considerably by subjecting the plates to an additional incubation period at 43 degrees C in the presence of a buffer at pH 5.3. by replicating these colonies on other Petri plates containing the appropriate media, it is possible to assess rapidly, not only the degree of catabolic repression of the cellulase production by glucose, but also, in a semiquantitative way, the amount of enzymes produced.