1AHX

ASPARTATE AMINOTRANSFERASE HEXAMUTANT

Summary for 1AHX

• Entry DOI: 10.2210/pdb1ahx/pdb
• Descriptor: ASPARTATE AMINOTRANSFERASE, PYRIDOXAL-5'-PHOSPHATE, HYDROCINNAMIC ACID, ... (4 entities in total)
• Functional Keywords: transferase (aminotransferase)
• Biological source: Escherichia coli
• Cellular location: Cytoplasm: P00509
• Total number of polymer chains: 2
• Total formula weight: 88069.22

Authors

Malashkevich, V.N.,Jansonius, J.N. (deposition date: 1995-02-21, release date: 1995-09-15, Last modification date: 2022-02-16)

Primary citation

Malashkevich, V.N.,Onuffer, J.J.,Kirsch, J.F.,Jansonius, J.N.
Alternating arginine-modulated substrate specificity in an engineered tyrosine aminotransferase.
Nat.Struct.Biol., 2:548-553, 1995

PubMed Abstract: Mutation of six residues of Escherichia coli aspartate aminotransferase results in substantial acquisition of the transamination properties of tyrosine amino-transferase without loss of aspartate transaminase activity. X-ray crystallographic analysis of key inhibitor complexes of the hexamutant reveals the structural basis for this substrate selectivity. It appears that tyrosine aminotransferase achieves nearly equal affinities for a wide range of amino acids by an unusual conformational switch. An active-site arginine residue either shifts its position to electrostatically interact with charged substrates or moves aside to allow access of aromatic ligands.

PubMed: 7664122
DOI: 10.1038/nsb0795-548

Experimental method

X-RAY DIFFRACTION (2 Å)