海洋細菌Ｖｉｂｒｉｏ ｓｐ．ＡＸ‐４の産生するβ‐１，３‐キシラナーゼのウスバアオノリによる誘導

Abstract

In the extract from acetone powder of topshell hepatopancreas, the activity of β-1, 3-xylanase is too low to isolate protoplasts from algal thalli. In our previous study, β-1, 3-xy-lanase was prepared from Vibrio sp. AX-4 by using β-1, 3-xylan as an inducer, and was add-ed to the preparation of algal cell wall-degrading enzymes. Since the habitat of Surikogizuta Caulerpa racemosa var. laete-virens which was used as a material for β-1, 3-xylan is limited to a particular region, research for the other materials was undertaken in the present study with regard to five species of green algae, four of brown, four of red, and three of land plants. Dry powder of a green alga, Usuba-aonori Enteromorpha linza was found to be most useful for inducing β-1, 3-xylanase in the culture fluid. The enzyme in the culture fluid containing the Usuba-aonori extract was partially purified by ammonium sulfate precipitation and successive Sephadex G-100 column chromatography. The active fractions were pooled and concentrated to 0.85unit/ml. We tried to isolate protoplasts from Oba-asakusa-nori Porphyra tenera var. tamatsuensis by using an enzyme mixture containing this β-1, 3-xylanase and were able to obtain a large number of protoplasts from the algal thalli.