|
|
||
|
|
|
|
|
UniProt functional annotation for Q9ASY9 | ||
|
|
|
|
|
|
||
| UniProt code: Q9ASY9. |
|
||
| Organism: | |
Arabidopsis thaliana (Mouse-ear cress). |
| Taxonomy: | |
Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae; rosids; malvids; Brassicales; Brassicaceae; Camelineae; Arabidopsis. |
|
||
|
||
| Function: | |
Involved in thiamine salvage by hydrolyzing the thiamine breakdown product 4-amino-5-aminomethyl-2-methylpyrimidine (amino-HMP) to 4-amino-5-hydroxymethyl-2-methylpyrimidine (HMP) (PubMed:25014715). Has a high formylamino-HMP amidohydrolase activity (PubMed:25014715). No activity with other thiamine degradation products such as thiamine mono- or diphosphate, oxothiamine, oxythiamine, thiamine disulfide, desthiothiamine or thiochrome as substrates (PubMed:25014715). Does not display thiaminase II activity, as it is unable to hydrolyze thiamine (PubMed:25014715). Is able to carry out two successive steps in the salvage of thiamine breakdown product, whereas two separate enzymes are required in Bacillus species (Probable). May also serve a damage pre- emption function by hydrolyzing products that would otherwise do harm (Probable). {ECO:0000269|PubMed:25014715, ECO:0000305|PubMed:25014715}. |
|
||
| Catalytic activity: | |
Reaction=4-amino-5-aminomethyl-2-methylpyrimidine + H2O = 4-amino-5- hydroxymethyl-2-methylpyrimidine + NH4(+); Xref=Rhea:RHEA:31799, ChEBI:CHEBI:15377, ChEBI:CHEBI:16892, ChEBI:CHEBI:28938, ChEBI:CHEBI:63416; EC=3.5.99.2; Evidence={ECO:0000269|PubMed:25014715}; |
| Catalytic activity: | |
Reaction=H2O + N-formyl-4-amino-5-aminomethyl-2-methylpyrimidine = 4- amino-5-aminomethyl-2-methylpyrimidine + formate; Xref=Rhea:RHEA:46212, ChEBI:CHEBI:15377, ChEBI:CHEBI:15740, ChEBI:CHEBI:63416, ChEBI:CHEBI:85895; Evidence={ECO:0000269|PubMed:25014715}; |
| Biophysicochemical properties: | |
Kinetic parameters: KM=70 uM for N-formyl-4-amino-5-aminomethyl-2-methylpyrimidine {ECO:0000269|PubMed:25014715}; KM=1816 uM for 4-amino-5-aminomethyl-2-methylpyrimidine {ECO:0000269|PubMed:25014715}; Note=kcat is 0.00281 sec(-1) for formylamino-HMP. kcat is 0.00015 sec(-1) for amino-HMP. {ECO:0000269|PubMed:25014715}; |
| Pathway: | |
Cofactor biosynthesis; thiamine diphosphate biosynthesis. {ECO:0000305}. |
| Tissue specificity: | |
Expressed in roots and shoots. {ECO:0000269|PubMed:25014715}. |
| Developmental stage: | |
Expression increases during seed development. {ECO:0000269|PubMed:25014715}. |
| Disruption phenotype: | |
No visible phenotype. {ECO:0000269|PubMed:25014715}. |
| Miscellaneous: | |
[Isoform 1]: Used for 3D-structure determination. |
| Similarity: | |
Belongs to the thiaminase-2 family. {ECO:0000305}. |
Annotations taken from UniProtKB at the EBI.