1UU1: Complex Of Histidinol-Phosphate Aminotransferase (Hisc) From Thermotoga Maritima (Apo-Form)

Citation:
Abstract
In histidine biosynthesis, histidinol-phosphate aminotransferase catalyzes the transfer of the amino group from glutamate to imidazole acetol-phosphate producing 2-oxoglutarate and histidinol phosphate. In some organisms such as the hyperthermophile Thermotoga maritima, specific tyrosine and aromatic amino acid transaminases have not been identified to date, suggesting an additional role for histidinol-phosphate aminotransferase in other transamination reactions generating aromatic amino acids. To gain insight into the specific function of this transaminase, we have determined its crystal structure in the absence of any ligand except phosphate, in the presence of covalently bound pyridoxal 5'-phosphate, of the coenzyme histidinol phosphate adduct, and of pyridoxamine 5'-phosphate. The enzyme accepts histidinol phosphate, tyrosine, tryptophan, and phenylalanine, but not histidine, as substrates. The structures provide a model of how these different substrates could be accommodated by histidinol-phosphate aminotransferase. Some of the structural features of the enzyme are more preserved between the T. maritima enzyme and a related threonine-phosphate decarboxylase from S. typhimurium than with histidinol-phosphate aminotransferases from different organisms.
PDB ID: 1UU1Download
MMDB ID: 27110
PDB Deposition Date: 2003/12/12
Updated in MMDB: 2007/10
Experimental Method:
x-ray diffraction
Resolution: 2.38  Å
Source Organism:
Similar Structures:
Biological Unit for 1UU1: dimeric; determined by author and by software (PQS)
Molecular Components in 1UU1
Label Count Molecule
Proteins (2 molecules)
2
Histidinol-phosphate Aminotransferase(Gene symbol: TM1040)
Molecule annotation
Chemicals (4 molecules)
1
2
2
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
.