Compared with many different amylases that are able to hydrolyze only α-d-(1,4)- glycosidic bonds, maltogenic amylases exhibit catalytic versatility: hydrolysis of. The physiological functions of two amylolytic enzymes, a maltogenic amylase ( MAase) encoded by yvdF and a debranching enzyme (pullulanase) encoded by . Enzymatic characterization of a maltogenic amylase from. Lactobacillus gasseri ATCC expressed in Escherichia coli. Ko-Woon Oh a., Myo-Jeong Kim b.
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Proposed model of starch and glycogen amhlase in Bacillus spp. This article has been cited by other articles in PMC. Gene cloning and overproduction of ThMA was described recently 5. Use of G7 by MAase in vivo.
Isoamylase, a debranching enzyme that is found mainly in plants, is also expressed constitutively and involved in the synthesis of starch 3. The shape of the active site cleft of ThMA explains much slower hydrolysis of starch than CDs by the enzyme. The inset shows the line fitting of the elution time amylade logarithm of the molecular weight of the size markers.
Maltogenic amylase from Bacillus stearothermophilus expressed in Bacillus subtilis
Separation and quantitative-determination of nanogram quantities of maltodextrins and isomaltodextrins by thin-layer chromatography. Preparation of glucose dehydrogenase GluDH reagent: Samples were eluted with a linear gradient of 0. The malZ gene of Escherichia colia member of the maltose regulon, encodes a maltodextrin glucosidase. The two strains in cultures containing G7 as the carbon source had logarithmic growth phases of similar lengths 16 to 18 hlonger than those of strains in cultures containing glucose or maltose as the carbon source data not shown.
The yvdF glg strain exhibited an intermediate decrease. A closely linked enzyme, CGTase, is hypothesized to have evolved from an ancestral hydrolase on the aylase of sequence and phylogenetic analysis Prev Next Table of Contents.
Maltogenic amylase (WHO Food Additives Series 40)
Molecular cloning and biochemical characterization of the first archaeal maltogenic amylase from the hyperthermophilic archaeon Thermoplasma volcanium GSS1. The first solution was rotated according to the noncrystallographic symmetry NCSand a translation search along the xy plane was performed, which was followed by a translation search along the z -axis to correlate the relative z -positions of the two solutions.
The calculations generated the final solutions with an R -factor of PTS can be recovered in pure form from an enzyme reaction mixture. Thus, the pullulanase has a specific preference for side chains with DP of 3 to 5, which are the lowest DP that can be hydrolyzed by glycogen phosphorylase The docking of the substrate molecule did not require reorientation of the protein amino acid side chains and change in torsion angles of substrate.
One group of these, maltogenic amylases MAases; 1 EC 3. The catalytic residues of ThMA would be reached only by the disordered part of starch.
Suzuki for assistance during data collection at Photon Factory PF. The vegetative cells of B. Open in a separate window. YvdK readily catalyzes the phosphorylysis of maltose to yield glucoseP and glucose.
Glycogen samples from the amyX glg and glg DM strains exhibited average molecular masses two and three times larger, respectively, than that of glycogen from the glg mutant. However, glycogen is barely detected in B. Total areas in the HPAEC chromatogram for bovine glycogen at various concentrations were used as standards. Overexpression, purification and preliminary X-ray analysis of pullulanase from Bacillus subtilis strain The final model at 2. In the absence of the enzyme, bacteria accumulated structurally modified glycogen forms comprising a high number of branches with DP of 4.
Support Center Support Center. Search for related content. The plate was dried and the contents were visualized by being dipped into a solution containing 0.
The black boxes represent the catalytic residues. The expression of MAase in E. Google Scholar Articles by Kim, J. Four glucosyl residues remaining in the side chain of glycogen would then be preferably cleaved at the branch point by pullulanase. Expression of the promoter for the maltogenic amylase gene in Bacillus subtilis This solution can be stored for two weeks at room temperature not in a refrigerator. CDase Oand A. Figure 2 asize exclusion column chromatography of ThMA and size marker proteins.
The two molecules exhibit the same molecular contacts as the ThMA dimer does. In Klebsiella oxytocathe open reading frames for CDase and an extracellular enzyme CGTase are clustered on the chromosomal DNA together with genes coding for products homologous to the maltose and linear maltodextrin uptake system