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A newly isolated, anaerobic, mesophillic bacterium, Clostridium sp. strain YK-3, ferments pentoses, hexoses, oligosaccharides and polysaccharides, such as soluble starch and glycogen, to ethanol and acetate. The potential of this strain for ethanol and amylase production has been examined. Ethanol was the major product and acetate a minor one. The organism could grow with soluble starch in the presence of 40 g ethanol/l. Extracellular α-amylase activity was detected when the strain was cultivated with soluble starch, glycogen or dextrin. The optimum pH of this amylase was 5.5 to 7.5 with an optimum temperature of 50°C.

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/?-(l->4)-D-Glucanase(II) was isolated and purified to homogeneity on SDS-electrophoresis from brewing barley malt. This enzyme had an endo-hydrolase action pattern on /?-glucan prepared from the same malt, while the enzyme formed precipitates in the reaction mixture. These precipitates (P-I) as a whole were composed of /?-(l->3) and (l->4) linkages in a molar ratio of 27.6: 72.4. The P-I was separated into two parts and analyzed; they had mainly linear /?-(l->4) linkages. Whencellotetraose or 3-O-/?-cellotriosyl-D-glucose was used as a substrate for /?-(l-»4)-dglucanase(II), insoluble materials were similarly formed in reaction mixture. These water-insoluble materials were cellooctaose and 3-0-/?-cellooctaosyl-D-glucose, respectively. These results suggest that /?-(l->4)-D-glucanase(II) catalyzed the transfer of /?-D-glucosyl residues from each oligosaccharide to C4-OHof the non-reducing residue in each of them, and the resulting products from the transglucosylation precipitated in the reaction mixture. When/?-glucanases prepared from malt are incubated with solutions containing malt /?glucan, insoluble materials are formed in the reaction mixture. In a previous paper1) of this series, we described some properties of three /?glucanases which participated in the formation of precipitates in malt, two of which were different from knownenzymes. One of them was /Kl->4)-D-glucanase(I), with a molecular weight of 37,000 and an optimum pH of 5.0. The other enzyme was /?-(1-»4)-dglucanase(II), with a molecular weight of 49,000 and an optimum pH of4.5. In addition, it was found that /?-(l->4)-D-glucanase(II) was relatively stable to heat treatment and formed most of the precipitates in the reaction mixture. MATERIALS AND METHODS Materials. Two-rowed brewing barley malt was obtained from the Providence Co., France. Standard proteins: bovine serum albumin (mol. wt. 67,000); ovalbumin (mol. wt. 45,000); chymotrypsinogen (mol. wt. 26,000); myoglobin (mol. wt. 17,800) and cytochrome c (mol wt. 12,500) for the molecular weight estimation were obtained from the Sigma Chemical Co., U.S.A. DEAE-Sephadex A-50, CM-Sephadex C-50, and Sephadex G-75 were obtained from Pharmacia, Sweden. Hydroxyapatite was obtained from Seikagaku Kogyo Co., Ltd., Japan. All other reagents used were guaranteed grade purchased from Seikagaku Kogyo Co., Wako Pure Chemical Co., and Nakarai Chemicals Co., Japan.