ABSTRACT
The amino acid and sugar composition of the enzyme protein, the effect of urea, sodium dodecyl sulphate and Concanavalin A on the purified alpha-galactosidase (EC 3.2.1.22) from the mold Cephalosporium acremonium has been studied. The results obtained by gas liquid chromatography indicated the presence of N-acetylglucosamine, mannose, galactose and N-acetylneuramic acid in the molar proportions 2:7:3:11. The presence of two types of Asn-linked oligosaccharide structures in the enzyme molecule is assumed. The alpha-galactosidase liberates alpha(1-3), alpha(1-4) and alpha(1-6)-linked D-galactose units from various synthetic and natural substrates which have been tested. The effects of pH, substrate concentration and temperature on the catalytic activity of the enzyme are described. The purified alpha-galactosidase also exhibited a lectin activity with an affinity towards glucose, and to some extent mannose.
Subject(s)
Acremonium/enzymology , Galactosidases/metabolism , Amino Acids/analysis , Carbohydrates/analysis , Chromatography, Gas , Enzyme Stability , Galactosidases/antagonists & inhibitors , Galactosidases/chemistry , Galactosidases/isolation & purification , Hydrogen-Ion Concentration , Kinetics , Substrate Specificity , TemperatureABSTRACT
Different methods for preparing alpha-galactosidase from the culture fluid of the micromycete Cephalosporium sp. 237 were tested. They included precipitation with ethanol, isopropanol, and acetone. Precipitation with two volumes of acetone gave the best results with respect to specific activity (12 units) and yield of the enzyme (78%). Properties of alpha-galactosidase (optimum pH at 5.5, temperature optimum at 40 degrees C. thermolability, etc), when different substrates were used, were examined.
Subject(s)
Acremonium/enzymology , Galactosidases/isolation & purification , alpha-Galactosidase/isolation & purification , Hydrogen-Ion Concentration , Methods , Temperature , alpha-Galactosidase/metabolismABSTRACT
The review discusses properties, distribution and potential use of microbial alpha-galactosidase (alpha-D-galactoside galactohydrolase, EC 3.2.1.22), the enzyme catalyzing degradation of alpha-D-galactoside bonds. Recent years have witnessed many publications describing microbial alpha-galactosidase which, in contrast to the similar enzyme from higher plants, has been poorly studied. The microbial enzyme has certain specificities: a smaller substrate specificity, existence in one molecular form, etc. The present communication is an attempt to systematize the data about microbial alpha-galactosidase and to outline the most important investigations for the future.
Subject(s)
Bacteria/enzymology , Fungi/enzymology , Galactosidases/analysis , alpha-Galactosidase/analysis , Animals , Blood Group Antigens , Enzyme Induction , Food Technology , Humans , Kinetics , Substrate Specificity , Temperature , alpha-Galactosidase/isolation & purification , alpha-Galactosidase/metabolismABSTRACT
The capacity for biosynthesis of alpha-galactosidase was examined in 89 yeast cultures belonging to 21 genera during submerged cultivation on a medium containing dry whey. This capacity was found only in one genus, namely Schwanniomyces. Optimal cultivation conditions were selected for the strain Schw. alluvius 1167 that showed the highest alpha-galactosidase activity. As a result, activity of alpha-galactosidase was increased 4.8 times as compared with the initial level.
Subject(s)
Galactosidases/analysis , Yeasts/enzymology , alpha-Galactosidase/analysis , Species SpecificityABSTRACT
The capacity to synthesize alpha-D-galactosidase (EC 3.2.1.22), alpha-D-mannosidase (EC 3.2.1.24), alpha-L-fucosidase (EC 3.2.1.51) and beta-D-acetylglucose aminidase (EC 3.2.1.30) was tested among 100 different cultures of soil microscopic fungi and actinomycetes. Two genera of micromycetes, viz. Scopulariopsis and Aposphaeria, which had not been known as producing alpha-D-galactosidase, were found, as well as several new species of the genus Penicillium: Pen. canescens, Pen. claviforme, Pen. cyclopium, Pen. daleae, Pen. frequentans, Pen. piscarum, Pen. simplicissimu, Pen. thomii.
