Cloned (Comment) | Organism |
---|---|
expression of the truncated mutant enzyme, B-512FMC dextransucrase, in Escherichia coli | Leuconostoc mesenteroides |
Protein Variants | Comment | Organism |
---|---|---|
additional information | construction of a truncated mutant of enzyme B-512F, the mutant shows sigmoidal shaped curves when the initial velocities are plotted against the concentration of added dextran. The increase in the reaction rate and the decrease in the sigmoidal curve with increasing dextran concentrations indicate that dextran binds at a noncatalytic or allosteric site to give a more active enzyme | Leuconostoc mesenteroides |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetic analysis of the low-molecular-weight products D-glucose, D-fructose, leucrose and isomaltodextrins formed during the synthesis of dextran by B-512FMC dextransucrase, overview | Leuconostoc mesenteroides |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
sucrose + [(1,6)-alpha-D-glucosyl]n | Leuconostoc mesenteroides | a highly processive mechanism of dextran biosynthesis, overview | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1,6)-alpha-D-glucosyl]n | Leuconostoc mesenteroides B-512FMC | a highly processive mechanism of dextran biosynthesis, overview | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Leuconostoc mesenteroides | - |
- |
- |
Leuconostoc mesenteroides B-512FMC | - |
- |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
sucrose + [(1->6)-alpha-D-glucosyl]n = D-fructose + [(1->6)-alpha-D-glucosyl]n+1 | involvement of the three conserved amino acids (Asp551, Glu589, and Asp662) in the organic reaction enzyme mechanism for the biosynthesis of dextran at the active site of dextransucrase by the insertion mechanism addition of D-glucose to the reducing-end of a growing dextran chain | Leuconostoc mesenteroides |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
sucrose + isomaltose | - |
Leuconostoc mesenteroides | D-fructose + isomaltotriose | - |
? | |
sucrose + isomaltose | - |
Leuconostoc mesenteroides B-512FMC | D-fructose + isomaltotriose | - |
? | |
sucrose + [(1,6)-alpha-D-glucosyl]n | a highly processive mechanism of dextran biosynthesis, overview | Leuconostoc mesenteroides | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1,6)-alpha-D-glucosyl]n | the enzyme performs dextran synthesis from sucrose, but D-glucose and sucrose are no initiator primers. Both D-glucose and dextran are covalently attached to B-512FMC dextransucrase at the active site during polymerization. The D-glucose moieties of sucrose are added to the reducing ends of the covalently linked growing dextran chains. Asp551, Glu589, and Asp 622 at the active sites of glucansucrases participate in the polymerization of dextran and related glucans from a single active site by the addition of the D-glucose moiety of sucrose to the reducing ends of the covalently linked glucan chains in a two catalytic-site, insertion mechanism overview. In the early stages of the reaction the products are D-glucose, D-fructose, leucrose, and isomaltodextrins in low, exponentially decreasing amounts from DP 2-5, with minuscule amounts of DP 6-12, but exponentially decreasing amounts of isomaltodextrins, down to minuscule amounts of DP 20-25, overview | Leuconostoc mesenteroides | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1,6)-alpha-D-glucosyl]n | a highly processive mechanism of dextran biosynthesis, overview | Leuconostoc mesenteroides B-512FMC | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? | |
sucrose + [(1,6)-alpha-D-glucosyl]n | the enzyme performs dextran synthesis from sucrose, but D-glucose and sucrose are no initiator primers. Both D-glucose and dextran are covalently attached to B-512FMC dextransucrase at the active site during polymerization. The D-glucose moieties of sucrose are added to the reducing ends of the covalently linked growing dextran chains. Asp551, Glu589, and Asp 622 at the active sites of glucansucrases participate in the polymerization of dextran and related glucans from a single active site by the addition of the D-glucose moiety of sucrose to the reducing ends of the covalently linked glucan chains in a two catalytic-site, insertion mechanism overview. In the early stages of the reaction the products are D-glucose, D-fructose, leucrose, and isomaltodextrins in low, exponentially decreasing amounts from DP 2-5, with minuscule amounts of DP 6-12, but exponentially decreasing amounts of isomaltodextrins, down to minuscule amounts of DP 20-25, overview | Leuconostoc mesenteroides B-512FMC | D-fructose + [(1,6)-alpha-D-glucosyl]n+1 | - |
? |
Synonyms | Comment | Organism |
---|---|---|
B-512F dextransucrase | - |
Leuconostoc mesenteroides |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
23 | - |
assay at | Leuconostoc mesenteroides |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
5.2 | - |
- |
Leuconostoc mesenteroides |