Physiological studies on induction and catabolite repression of beta-xylosidase and endoxylanase in Streptomyces sp CH-M-1035

The specificity of induction of beta-xylosidase and endoxylanase from Streptomyces sp. CH-M-1035 was investigated using mono-, di- and poly-saccharides, among other compounds. This microorganism was able to grow on all carbon sources except cellulose microcrystalline and methyl-beta-D-xylopyranoside. beta-Xylosidase was induced by larchwood xylan, birchwood xylan, oat spelts xylan and D-xylose. Basal levels of activity were obtained in sucrose, lactose, maltose and pectin. Endoxylanase activity was induced in presence of xylans, D-xylose, sucrose and D-arabinose. Both enzymes, beta-xylosidase and endoxylanase, were repressed by the addition of glucose, glycerol and succinic acid to the culture medium containing 1% birchwood xylan. On the other hand, addition of methyl-beta-D-xylopyranoside in the same conditions induced beta-xylosidase but not endoxylanase synthesis. An unexpected stimulatory effect was observed on beta-xylosidase biosynthesis when pyruvic acid was added to the culture medium independently of the xylan used.