Cloned (Comment) | Organism |
---|---|
DNA and amino acid sequence determination and analysis, sequence comparisons | Zea mays |
Protein Variants | Comment | Organism |
---|---|---|
additional information | generation of mutant isa2-339 | Zea mays |
additional information | generation of mutant su1-4582 | Zea mays |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
chloroplast | - |
Zea mays | 9507 | - |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
75000 | - |
x * 75000, SDS-PAGE | Zea mays |
80000 | - |
x * 80000, about, SDS-PAGE | Zea mays |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Zea mays | - |
gene isa2 | - |
Zea mays | B6U0X5 | gene su-1 | - |
Purification (Comment) | Organism |
---|---|
native subunit ISA2 from leaves by anion exchange chromatography, ultrafiltration, and gel filtration, separation from subunit ISA1 | Zea mays |
native subunit ISAI from leaves by anion exchange chromatography, ultrafiltration, and gel filtration, separation from subunit ISA2 | Zea mays |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
endosperm | the ISA1 homomer does not provide the full physiological function of ISA activity in maize leaves. This is in contrast to the endosperm, where loss of ISA2, and thus the ISA1/ISA2 heteromeric enzyme, can be tolerated without major defects | Zea mays | - |
leaf | three ISA activity forms are observed in leaves, two ISA1/ISA2 heteromultimers and one ISA1 homomultimer. ISA1 homomultimer activity exists in mutants lacking ISA2. Mutants without ISA2 differ in leaf starch content, granule morphology, and amylopectin structure compared with nonmutants or lines lacking both ISA1 and ISA2. The data imply that both the ISA1 homomultimer and ISA1/ISA2 heteromultimer function in the maize leaf. The ISA1 homomer does not provide the full physiological function of ISA activity in maize leaves. This is in contrast to the endosperm, where loss of ISA2, and thus the ISA1/ISA2 heteromeric enzyme, can be tolerated without major defects | Zea mays | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
amylopectin + H2O | - |
Zea mays | ? | - |
? | |
maize starch + H2O | - |
Zea mays | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | x * 75000, SDS-PAGE | Zea mays |
? | x * 80000, about, SDS-PAGE | Zea mays |
Synonyms | Comment | Organism |
---|---|---|
ISA1 | - |
Zea mays |
ISA2 | - |
Zea mays |
isoamylase-type starch debranching enzyme 1 | - |
Zea mays |
isoamylase-type starch debranching enzyme 2 | - |
Zea mays |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme belongs to the glycosyl hydrolase family 13 GH13, and harbors a carbohydrate-binding module family 48 (CBM48) domain | Zea mays |
malfunction | the ISA1 homomer does not provide the full physiological function of ISA activity in maize leaves. This is in contrast to the endosperm, where loss of ISA2, and thus the ISA1/ISA2 heteromeric enzyme, can be tolerated without major defects. Mutants without ISA2 differ in leaf starch content, granule morphology, and amylopectin structure compared with nonmutants or lines lacking both ISA1 and ISA2, mutant phenotypes, overview | Zea mays |
malfunction | the ISA1 homomer does not provide the full physiological function of ISA activity in maize leaves. This is in contrast to the endosperm, where loss of ISA2, and thus the ISA1/ISA2 heteromeric enzyme, can be tolerated without major defects. Mutants without ISA2 differ in leaf starch content, granule morphology, and amylopectin structure compared with nonmutants or lines lacking both ISA1 and ISA2. Plastids from maize leaves lacking ISA2 exhibit a nearly normal appearance with the exception that starch granules appear to be slightly smaller than in wild-type, mutant phenotypes, overview | Zea mays |