ENHANCEMENT OF ACTIVITY OF MICROORGANISMS CULTIVATED WITH BIOMASS SUPPORT PARTICLES

点击翻译按钮获取中文摘要

This work was undertaken to develop a new method for producing immobilized microorganisms which have high activity and are suitable for industrial use. First, proteins in the cells and supernatant, which were produced by suspension culture of filamentous fungus Rhizopus chinensis and by cultivating the cells in porous urethane beads, were analyzed by using SDS-PAGE.Then, one of the proteins in supernatant obtained by suspension culture of Rh. chinensis was purified. The principla results are as follows : (1) The SDS-PAGE of the proteins in the cells and in the supernatant, both of which were obtained by suspension culture and by cultivating the cells in porous urethane beads, showed that the patterns of electrophoresis were considerably different. This means that different kinds of proteins were produced in the supernatant and cells, and this depended on the cultivation methods. (2) One of the proteins in the supernatant of the suspension culture was purified by use of ion-exchange chromatography, hydrophobic interaction chromatography and gel filtration chromatography. (3) The purified protein was a monomeric enzyme consisting of a single polypeptide chain and had a molecular weight of 32,000. The optimum reaction temperature and optimum pH were 37ﾟC and 5.5, respectively. A lyophilized sample of the purified protein had an ester-hydrolyzing activity of 81.8 Unit/mg, but did not have any interesterification activity. From these results, we concluded that Rh. chinensis secreted lipase having high ester-hydrolyzing activity and have lipase with high interesterification activity in the cells.