@article{oai:fukuyama-u.repo.nii.ac.jp:00007971, author = {岩本, 博行 and 廣瀬, 順造 and 廣海, 啓太郎}, issue = {2}, journal = {福山大学工学部紀要}, month = {Mar}, note = {P(論文), Starch-debranching-enzyme hydrolyzes the α-1,6-glucosidic linkages of starch and other α-glucans. Isoamyase and pullulanase belong to this enzyme group, and are key enzymes for the industrial production of glucose, maltose and other oligosaccharides from starch. In this paper, we examined the interaction between pullulanase from Klebsiella pneumomae and α-, β-, and γ-cyclodextrins by means of inhibition studies of the enzyme activity, UV and fluorescence difference spectroscopy, and flow calorimetry. All the above cyclodextrins were found to be competitive inhibitors, but the inhibition and dissociation constants of β-cyclodextrin were two orders of magnitude less than those of α- and γ-cyclodextrins. The UV and fluorescence spectral change (excitation at 295 nm) induced by the addition of β-cyclodextrin were significantly different from those of other cyclodextrins. In the calorimetric analysis, only β-cyclodextrin showed a positive entropy change upon binding with the enzyme. Moreover, preliminary kinetic studies were done on the binding of the enzyme with cyclodextrins by following the increase of the fluorescence intensity with a micro-stopped-flow apparatus. The apparent first-order rate constants, K_, for α- and γ-cyclodextrins were independent of the concentration of cyclodextrins. In contast, β-cyclodextrin showed a hyperbolic cyclodextrin concentration dependence of K_. judged from these results, the binding mode of β-cyclodextrin is subtly different from those of α- and γ-cyclodextrins.}, pages = {71--80}, title = {澱粉枝切り酵素プルラナーゼとシクロデキストリンとの相互作用}, volume = {19}, year = {1996} }