1975 Volume 23 Issue 6 Pages 1304-1308
Some physicochemical properties and amino acid compositions of dextranases from Brevibacterium fuscum and Penicillium funiculosum IAM 7013 were investigated. The values of 4.35S and 4.37S, respectively, were obtained for the sedimentation constant (S20, w) of dextranases from B. fuscum and P. funiculosum, and their isoelectric points (pI) were also determined 4.17 and 4.19, respectively. Gel filtration on Bio Gel P-100 indicated the molecular weight 5.5×104 for B. fuscum and 4.4×104 for P. funiculosum, and their intrinsic viscosities were 0.038 dl/g and 0.027 dl/g, respectively. Amino acid analysis suggested that dextranase of B. fuscum was found to be composed of more than 429 amino acid residues of 17 amino acids and the enzyme of P. funiculosum contained more than 349 of the residues of 18 amino acids. The composition of the enzymes was very similar except for two residues of cystine which were contained in only P. funiculosum dextranase. Dextranase of B. fuscum contained 11 moles of neutral sugars as glucose and 3 moles of amino sugars as glucosamine per one mole of the enzyme, and in P. funiculosum, the former was 10 moles and the later was found to be 1 mole. The results of staining of the enzymes in disc electrophoresis gels by periodic acid and fuchsin-sulfite, and the observations above mentioned indicated that both dextranases were glycoprotein.
