BETA-MANNANASES ELABORATED BY THE PHYTO-PATHOGEN XANTHOMONAS-CAMPESTRIS

The phytopathogen Xanthomonas campestris when grown on several polysaccharide substrates, including galactomannan, produced β-mannanases and carboxymethylcellulases which were present as cell wall-, or membrane-bound constituents, and also in the extracellular medium. The extracellular β-mannanases are constitutive enzymes. Cell-bound β-mannanases could be partially solubilized by Triton X-100, but this treatment could not release cell-bound cellulase. This is the first report of the existence of a cell-bound β-mannanase. Cell-free and bound β-mannanases and carboxymethylcellulases were found to be of the endoenzyme type. © 1979 Springer-Verlag.