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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Previously, the yvdF promoter has been shown to be regulated by the spo0A gene in a positive manner In the extra sugar-binding space, an acceptor sugar molecule may be able to position either the C3- C4- or C6-OH group in a proper orientation for nucleophilic attack of the glycosyl-enzyme intermediate.
The vegetative cells of B. Debranching of the outer side chain of glycogen by pullulanase AmyX. However, some hydrolysis products ranging from G2 to G7 were detected in the wild type, but only a limited amount of such products was detected in the yvdF mutant.
The events occurring in the cytoplasm during sporulation are indicated in the circle. The size of the space appears to accommodate a disaccharide such as maltose rather easily, as a maltose molecule can be successfully docked into the space Fig. Properties of maltose-inducible alpha-glucosidase MalL sucrase-isomaltase-maltase in Bacillus subtilis: This article has been cited by other articles in PMC.
Read OD at nm. Isoamylase, a debranching enzyme that is found mainly in plants, is also expressed constitutively and involved in the synthesis of starch 3. Every other 20th residue positions are numbered. The results confirm that B. Physiological characterization of SusG, amyalse outer membrane protein essential for starch utilization by Bacteroides thetaiotaomicron.
The black boxes represent maktogenic catalytic residues. Modes of action of acarbose hydrolysis and transglycosylation catalyzed by a thermostable maltogenic amylase, the gene for which was cloned from a Thermus strain.
The increase in the correlation coefficient suggested that the peak was a correct solution. The solid line indicates the calculated curve for dimeric species. The accumulation of glucoseP via YvdK has not maltogejic observed in cell extracts because of the immediate use of glucoseP in subsequent metabolism. They are found in the same relative position in space as the corresponding residues in TAKA-amylase A.
Figure 4 Schematic drawings of products from reaction of acarbose with ThMA. In this model, the C4-OH group of a maltose at the nonreducing end naltogenic 3. Helpful advice from Drs. Different sugar molecules, including glucose, fructose, maltose, and cellobiose, can serve as acceptors for the transglycosylation.
Calculate the activity of the maltogenoc by reading D OD of sample dilutions on the standard curve and then multiplying by the corresponding dilution factors. However, to date, the physiological function of pullulanase encoded by amyX has not been investigated.
Bacillus subtilis contains a cyclodextrin-binding protein which is part of a putative ABC-transporter. National Center for Biotechnology InformationU. Dissolve mg maltotriose e. Glu is indicated by an asterisk whose substitution with histidine severely affects the transglycosylation activity of ThMA.
The idea of extra sugar-binding space playing an important role in the transglycosylation explains the effect of Glu mutation. Identification and enzymatic characterization of the maltose-inducible alpha-glucosidase MalL sucrase-isomaltase-maltase of Bacillus subtilis. Molecular cloning and nucleotide sequence of the glycogen branching enzyme gene glgB from Bacillus stearothermophilus and expression in Escherichia coli maltogfnic Bacillus subtilis.
The four genes most proximal to the promoter encode enzymes for the synthesis of glycogen, maltogwnic a branching enzyme glgBan ADP-glucose phyrophosphorylase glgC and glcDand a glycogen synthase glgA. The concentration of ThMA was 0.
Safety evaluation of the food enzyme maltogenic amylase from a
In this window In a new window. Fill the flask to the mark with the same buffer. The crystal structure of a maltogenic amylase from a Thermus strain was determined at 2. Crystallization Initial effort was put into the structure determination of Bacillus stearothermophilus maltogenic amylase BSMA whose crystallization condition we have reported Initial effort was put into the structure determination of Bacillus stearothermophilus maltogenic amylase BSMA whose crystallization condition mlatogenic have reported Assay conditions being as follows: The assumption requires a sugar-binding site adjacent to the main substrate-binding site.
The mechanism of glycogen degradation in Bacillus spp. Vegetative cells and endospores of the B. The starch-debranching enzymes isoamylase and pullulanase are both involved in amylopectin biosynthesis in amjlase endosperm.
A mono- or disaccharide occupying the space could serve as an acceptor maltkgenic to amylaes with a water molecule for attacking enzyme-substrate intermediate catalyzed by the same catalytic armory as shown in Fig.
Glycogen in the reactions with cell extract from the amyX or yvdF amyX mutant was hardly attacked compared to that in the reaction with cell extract from the wild type.
The cryoprotectant solution contained 0. This solution can be stored for two weeks at room temperature not in a refrigerator. MAases, NPases, and CDases are intracellular enzymes, maltkgenic implicates their biological roles in metabolizing small oligosaccharides, including CDs imported into the cells for energy generation, and storing them in the form of branched oligosaccharides under the condition of high concentration of glucose or maltose.
Maltogenic amylase from Bacillus stearothermophilus expressed in Bacillus subtilis
Suzuki for assistance during data collection at Photon Factory PF. This process exposes four glucosyl residues for hydrolysis by the pullulanase, which has a specific preference for G4 side chains. CDase Oand A. Related Content Load related web page information. More than two-thirds of the excluded surface is hydrophobic surface. We established that it naltogenic not the case for ThMA. The standard curve is a straight line passing through the origin and linear regression can therefore be applied.