Purification and Properties of an exo-α-Amylase fromPseudomonas stutzeri

Publisher Website
Google Scholar
Abstract
A maltotetraose-forming amylase from Pseudomonas stutzeri was highly purified by adsorption on starch granules and by chromatographies on Sephadex G-100 and DEAE-cellulose. The purified enzyme showed a single band in polyacrylamide gel electrophoreses with or without sodium dodecylsulfate. The optimum pH for enzyme action on starch was 6.0-6.5, and the optimum temperature was 45°C. The purified enzyme attacked starch from the non-reducing end to produce α-anomer oligosaccharides. This indicated that the enzyme was an exo-α-amylase which had not hitherto been found. The enzyme activity was markedly inhibited by the addition of Cu2+, Hg2+, N-bromosuccinimide and 2,3-butanedione. The molecular weight of the enzyme determined by the method of Weber and Osborn was about 5.7 × 104. The isoelectric point of the enzyme was estimated to be 5.3 by polyacrylamide gel electrofocusing. The Km and k0 values of this enzyme for starch, glycogen, short chain amylose and some maltooligosaccharides were calculated from Lineweaver-Burk plots.

This publication has 4 references indexed in Scilit: