Purification and some properties of a chitosanase of Nocardioides sp.

Chitosanases which degrade chitosan to glucosamine oligomers have been purified from several microorganisms, including bacteria (7,15,18,(21)(22)(23), fungi (4,19) and actinomycetes (5,8,(12)(13)(14)16,17).We found a thermostable chitosanase produced by Amycolatopsis sp.14).Although strain Cs0-2 is mesophile, it produced thermostable chitosanase (CsO-2 chitosanase).We also isolated a mesophile actinomycete, strain K-O1, producing a thermostable chitosanase (K-O1 chitosanase) different from Cs0-2 chitosanase.In this paper, we report on the identification of strain K-O1 and some properties of K-O1 chitosanase.Strain K-O1 was isolated from soil by the same method as the case of strain Cs0-2, and maintained on Bennet agar slants (14).Strain K-01 was identified in the following way: The isomeric form of diaminopimelic acid and sugars were determined by chromatography of whole-cell hydrolyzates on Cellulose glass plates (Merck, Darmstadt, Germany) as described by Becker et al. ( 1) and Staneck and Roberts (20).The mycolic acid was examined by the method of Goodfellow et al. ( 6).The phosphatidylethanolamine of the cell membrane was examined by the method of Minnikin et al. (11).Degradation tests of casein, xanthin, hypoxanthin, tyrosine, urea, and cellobiose were examined by the method of de Boer et al. (3).Lysozyme resistance was determined by the method of Berd (2).Chitosanase production by strain K-O1 was done in the following way: As seed culture, a loopful of the organism was inoculated into 20 ml of Bennet's liquid medium in a 100-ml Erlenmeyer flask, and was then incubated on a rotary shaker