The substance, which acted on the mycelial cells of Asp, oryzae was found in the culture fluid of a newly isolated bacterial strain. This organism seemed to belong to Bacillus circulans: gram-negative, spore-forming rods, (spore: oval, terminal to subterminal), motile, peritrichous flagella, reduces nitrate, acetylmethyl-carbionl-negative, acid from glucose-without gas. This active material was an enzyme with an optimum pH at 6.8, and precipitated in a 40-60% saturated solution of ammonium sulfate. The enzyme acted on the cell-wall and liberated hexose-polymer from the cell-walls of Asp. oryzae. but could not liberate any hexosamine or amino acid. This liberated hexose- polymer seemed to be a polymer of melibiose consisting of glucose and galactose. It seems that the polysaccharide is a cementing and coating material of the network of chitin fiber of the cell-walls. Specificity of the enzyme was very broad; the enzyme acted on the living cells of Asp, sojae, Mucor Mu-5, Pen. purpurogenum var., and heat treated cells of Saccharomyces saké, but was inactive on Rhizopus javanicus. This result may be assumed to indicate that the structure of the cell- wall of Asp. sojae, Pen. sp., and Mucor are similar to Asp. oryzae, but that of Rhizopus is different. This enzyme was produced during the sporulation of Bacillus circulans.
1. Most of the fungi tested in this study were found to be able to grow on D-glutamate medium (containing D-glutamate as the sole source of carbon and nitrogen). Several strains of them, belonging to Aspergillus, Penicillium or Monascus, could grow on D-glutamate medium as rapidly as on L-glutamate medium. 2. In these fungi, two types of D-glutamate oxidizing enzyme were found; the one was a specific D-glutamic oxidase and the other was a D- glutamic-aspartic oxidase. 3. Most of fungi tested were found to possess D-glutamic-aspartic oxidase, whereas, fungi belonging to Aspergillus oryzae possessed a specific D-glutamic oxidase. 4. These D-glutamate oxidizing enzymes were remarkably formed when the fungi were grown on D-glutamate containing medium, whereas a little enzyme activity was observed in fungi grown on a peptone-glucose medium. 5. The physiological significance of D-amino acid oxidizing enzymes are discussed here.
1) Three strains of tetrads-forming bacteria belonging to Pediococcus were isolated from beer. 2) Each strain was injurious against beer changing the flavor to abominable. It formed a compact deposit at the bottom of the bottle without showing notable turbidity upon the beer. 3) It is characterized chiefly by its strict growth-dependency toward mevalonic acid (hiochic acid). 4) The name Pediococcus mevalovorus nov. spec. has been proposed (mevalo-mevalonic acid, voro-to devour).
Several cross tests were carried out between a white methionineless mutant of Aspergillus oryzae and a yellow leucineless mutant of Asp. sojae. The mixed plating of two kinds of conidia onto a limitedly supplemented medium yielded brown prototrophic colonies in the frequency of 2-8 per 108 plated conidia. The new strains were quite stable even after sequential stransfers and partially equipped with hybrid characters. Four possible mechanisms were discussed in regard to the appearance of new strains.
1) The xylanase system produced by Aspergillus oryzae No. 8 in the wheat bran culture was able to hydrolyze xylan in a degradation limit of 90%. 2) By paper chromatography, the end products from xylan by this enzyme were demonstrated to be xylobiose, xylotriose and xylotetraose. 3) From the observation on the process of xylan digestion by this enzyme it was concluded that this system should be classified into liquefying xylanase or xylanase A. 4) When various xylo-oligosaccharides were used as substrates, it was observed that the higher polymer was hydrolyzed much faster than the lower. The innermost bonds of substrate molecules were most easily hydrolyzed. 5) A main products of xylan degradation by the enzyme system, xylobiose, xylotriose, xylotetraose and xylopentaose were isolated in a crystalline form or powder by applying the charcoal column technique.