Cloned (Comment) | Organism |
---|---|
gene UPB1, located on chromosome 22q11.2, DNA and amino acid sequence determination and analysis, sequence comparisons and genomic organization analysis, genotyping of beta-ureidopropionase deficient patients as well as the analysis of the mutations in a three-dimensional framework, PCR enzyme expression analysis, overview. Recombinant heterologous expression of wild-type and mutant enzymes in Escherichia coli strain C41(DE3)pRARE2, all mutations yield mutant beta-ureidopropionase proteins with significantly decreased activity | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
G235R | naturally occuring mutation and site-directed mutagenesis, inactive mutant. Mutation G235R introduces a large amino acid side chain for which there is no space available at this location. The larger structural rearrangements in the active site cavity required to prevent clashes with surrounding residues are expected to lead to enzyme inactivity and misfolding and defects in oligomerization, inability to obtain significant expression of soluble protein for this mutant | Homo sapiens |
L13S | naturally occuring mutation and site-directed mutagenesis, the mutation results in folding defects and oligomer assembly impairment, the mutant shows reduced activity compared to the wild-type enzyme | Homo sapiens |
R236W | naturally occuring mutation and site-directed mutagenesis, the mutant shows highly reduced activity compared to the wild-type enzyme | Homo sapiens |
R326Q | naturally occuring mutation and site-directed mutagenesis, the mutation results in folding defects and oligomer assembly impairment, inactive mutant | Homo sapiens |
S264R | naturally occuring mutation and site-directed mutagenesis,mutation S264R abolishes the hydrogen bond to Y314, which may be important for structural fixation of a residue stretch that is involved in shaping the entrance to the active site, the mutant shows reduced activity compared to the wild-type enzyme | Homo sapiens |
T359M | naturally occuring mutation and site-directed mutagenesis, the mutation results in folding defects and oligomer assembly impairment, the mutant shows highly reduced activity compared to the wild-type enzyme | Homo sapiens |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
43158 | - |
4 * 43158, sequence calculation, structure analysis by dynamic light scattering and circular dichroism spectroscopy, and modeling, overview | Homo sapiens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
3-ureidobutyrate + H2O | Homo sapiens | - |
2-methyl-beta-alanine + CO2 + NH3 | - |
? | |
3-ureidopropanoate + H2O | Homo sapiens | - |
beta-alanine + CO2 + NH3 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | Q9UBR1 | gene UPB1 | - |
Purification (Comment) | Organism |
---|---|
recombinant wild-type and mutant enzymes from Escherichia coli strain C41(DE3)pRARE2 by nickel affinity chromatography, desalting gel filtration, and cleavage of the tag by His-tagged 3C protease, followed by gel filtration and anion exchange chromatography | Homo sapiens |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
0.0167 | - |
purified recombinant detagged mutant L13S, pH and temperature not specified in the publication | Homo sapiens |
0.0558 | - |
purified recombinant detagged mutant S264R, pH and temperature not specified in the publication | Homo sapiens |
0.282 | - |
purified recombinant detagged wild-type enzyme, pH and temperature not specified in the publication | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
3-ureidobutyrate + H2O | - |
Homo sapiens | 2-methyl-beta-alanine + CO2 + NH3 | - |
? | |
3-ureidopropanoate + H2O | - |
Homo sapiens | beta-alanine + CO2 + NH3 | - |
? |
Subunits | Comment | Organism |
---|---|---|
tetramer | 4 * 43158, sequence calculation, structure analysis by dynamic light scattering and circular dichroism spectroscopy, and modeling, overview | Homo sapiens |
General Information | Comment | Organism |
---|---|---|
malfunction | beta-ureidopropionase deficient patients show neurological abnormalities (intellectual disabilities, seizures, abnormal tonus regulation, microcephaly, and malformations on neuro-imaging) and markedly elevated levels of N-carbamyl-beta-alanine and N-carbamyl-beta-aminoisobutyric acid in urine and plasma, phenotypes of six missense and one splice-site mutants, overview | Homo sapiens |
metabolism | beta-ureidopropionase is the third enzyme of the pyrimidine degradation pathway | Homo sapiens |
additional information | the catalytically crucial cysteine C233 performs the nucleophilic attack on the substrate resulting in the covalent acyl-enzyme complex. Residue R236 is part of the active site and has a putative role in binding the carboxyl group of the substrate. Analysis of a homology model of human beta-ureidopropionase generated using the crystal structure of the enzyme from Drosophila melanogaster indicated that the point mutations p.G235R, p.R236W and p.S264R lead to amino acid exchanges in the active site and therefore affect substrate binding and catalysis | Homo sapiens |