Protein Variants | Comment | Organism |
---|---|---|
additional information | the sucrase-free mutant lacks the entire sucrase domain and 69 amino acids of the C-terminus of isomaltase domain, the isomaltase function is unaffected by the mutation, sucrase function is missing | Suncus murinus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
7 | - |
maltose | wild-type sucrase-isomaltase | Suncus murinus | |
12.8 | - |
isomaltose | wild-type sucrase-isomaltase | Suncus murinus | |
13.6 | - |
isomaltose | mutant isomaltase | Suncus murinus | |
27.5 | - |
sucrose | wild-type sucrase-isomaltase | Suncus murinus | |
62.8 | - |
maltose | mutant isomaltase | Suncus murinus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
membrane | - |
Suncus murinus | 16020 | - |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
103000 | - |
1 * 103000, mutant sucrase-free isomaltase, SDS-PAGE | Suncus murinus |
106000 | - |
1 * 106000, isomaltase subunit of the wild-type enzyme, + 1 * 115000, sucrase subunit of the wild-type enzyme, SDS-PAGE | Suncus murinus |
115000 | - |
1 * 106000, isomaltase subunit of the wild-type enzyme, + 1 * 115000, sucrase subunit of the wild-type enzyme, SDS-PAGE | Suncus murinus |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Suncus murinus | - |
house musk shrew, contains 2 enzyme forms: a sucrase-free isomaltase and a sucrase-isomaltase | - |
Posttranslational Modification | Comment | Organism |
---|---|---|
glycoprotein | enzyme, especially the mutant enzyme, contains probably carbohydrates with terminal L-fucose, determined by lectin affinity, overview | Suncus murinus |
Purification (Comment) | Organism |
---|---|
sucrase-free isomaltase and a sucrase-isomaltase from a wild-type and a sucrase-deficient mutant line, from intestine, by temperature adsorption-desorption affinity chromatography on Sephadex gel | Suncus murinus |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
intestine | - |
Suncus murinus | - |
mucosa | - |
Suncus murinus | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
2.12 | - |
purified mutant sucrase-free isomaltase, maltase activity | Suncus murinus |
7.79 | - |
purified wild-type sucrase-isomaltase, sucrase activity | Suncus murinus |
8.08 | - |
purified wild-type sucrase-isomaltase, isomaltase activity | Suncus murinus |
12.3 | - |
purified mutant sucrase-free isomaltase, isomaltase activity | Suncus murinus |
14.5 | - |
purified wild-type sucrase-isomaltase, maltase activity | Suncus murinus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
amylose + H2O | n = 18, low activity of wild-type sucrase-isomaltase, very low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
glycogen + H2O | substrate from oyster, low activity of wild-type sucrase-isomaltase, very low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
isomaltose + H2O | best substrate for the mutant isomaltase | Suncus murinus | 2 D-glucose | - |
? | |
maltoheptaose + H2O | low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
maltohexaose + H2O | low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
maltopentaose + H2O | - |
Suncus murinus | ? | - |
? | |
maltose + H2O | best substrate of the wild-type sucrase-isomaltase | Suncus murinus | 2 D-glucose | - |
? | |
maltotetraose + H2O | low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
maltotriose + H2O | low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
additional information | substrate specificities of mutant isomaltase and wild-type sucrase-isomaltase, overview | Suncus murinus | ? | - |
? | |
pullulan + H2O | low activity | Suncus murinus | ? | - |
? | |
soluble starch + H2O | low activity of wild-type sucrase-isomaltase, very low activity of mutant isomaltase | Suncus murinus | ? | - |
? | |
sucrose + H2O | wild-type sucrase-isomaltase, no activity with the mutant isomaltase | Suncus murinus | D-glucose + D-fructose | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | 1 * 106000, isomaltase subunit of the wild-type enzyme, + 1 * 115000, sucrase subunit of the wild-type enzyme, SDS-PAGE | Suncus murinus |
monomer | 1 * 103000, mutant sucrase-free isomaltase, SDS-PAGE | Suncus murinus |
Synonyms | Comment | Organism |
---|---|---|
isomaltase | - |
Suncus murinus |
sucrase-isomaltase | - |
Suncus murinus |