Activating Compound | Comment | Organism | Structure |
---|---|---|---|
Triton X-100 | reagent in the preincubation mixture at concentrations 0.05-1% activates the enzyme by 45-72% | Solanum tuberosum |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
p-chloromercuribenzoate | reversible inactivation | Solanum tuberosum |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
83000 | - |
1 * 83000 + 1 * 95000 | Solanum tuberosum |
95000 | - |
1 * 83000 + 1 * 95000 | Solanum tuberosum |
178000 | - |
native enzyme | Solanum tuberosum |
520000 | - |
gel filtration | Solanum tuberosum |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
starch + H2O | Solanum tuberosum | - |
? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Solanum tuberosum | - |
potato, L. cul. var. "Danshaku" | - |
Purification (Comment) | Organism |
---|---|
- |
Solanum tuberosum |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
tuber | - |
Solanum tuberosum | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
8 | - |
- |
Solanum tuberosum |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
amylopectin + H2O | or the beta-limit dextrins, cleaves the branching points completely in vitro | Solanum tuberosum | maltose + maltooligosaccharides | hydrolysis of beta-limit dextrins forming maltotriose as main reaction product | ? | |
amylose + H2O | short chain | Solanum tuberosum | ? | - |
? | |
glycogen + H2O | cleaves the branching points completely in vitro | Solanum tuberosum | maltose + maltooligosaccharides | - |
? | |
glycogen + H2O | or the beta-limit dextrins | Solanum tuberosum | maltose + maltooligosaccharides | - |
? | |
maltopentaose + H2O | sugar immobilized on Sepharose 4B | Solanum tuberosum | ? | - |
? | |
additional information | direct debranching enzyme, attacks unmodified glycogen and/or amylopectin with hydrolysis of the 1,6-bond, smallest substrate is not known | Solanum tuberosum | ? | - |
? | |
additional information | distinguished from alpha-dextrin endo-1,6-alpha-glucosidase, EC 3.2.1.41, by the inability of isoamylase to attack pullulan, and by limited action on alpha-limit dextrins, action on glycogen however is complete in contrast to limited action by alpha-dextrin glucanohydrolase, 1,6-linkage hydrolysed only at branch point | Solanum tuberosum | ? | - |
? | |
phythoglycogen + H2O | highly branched polysaccharide, complete hydrolysis of the alpha-1,6-glucosidic bonds | Solanum tuberosum | ? | - |
? | |
starch + H2O | - |
Solanum tuberosum | ? | - |
? | |
starch + H2O | soluble starch, immobilized on Sepharose 4B | Solanum tuberosum | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | 1 * 83000 + 1 * 95000 | Solanum tuberosum |
Synonyms | Comment | Organism |
---|---|---|
potato isoamylase | - |
Solanum tuberosum |
Temperature Minimum [°C] | Temperature Maximum [°C] | Comment | Organism |
---|---|---|---|
60 | - |
not active above, amylopectin | Solanum tuberosum |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
45 | - |
- |
Solanum tuberosum |
50 | - |
amylopectin, incubated in the absence of substrate enzyme stable only up to 45°C | Solanum tuberosum |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
5.5 | 6 | amylopectin | Solanum tuberosum |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
4 | 8 | not active below, amylopectin | Solanum tuberosum |