1YAA

ASPARTATE AMINOTRANSFERASE FROM SACCHAROMYCES CEREVISIAE CYTOPLASM

Summary for 1YAA

• Entry DOI: 10.2210/pdb1yaa/pdb
• Descriptor: ASPARTATE AMINOTRANSFERASE, MALEIC ACID, PYRIDOXAL-5'-PHOSPHATE, ... (4 entities in total)
• Functional Keywords: transferase, aminotransferase
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Cellular location: Cytoplasm: P23542
• Total number of polymer chains: 4
• Total formula weight: 182899.04

Authors

Jeffery, C.J. (deposition date: 1998-01-27, release date: 1998-09-16, Last modification date: 2023-08-09)

Primary citation

Jeffery, C.J.,Barry, T.,Doonan, S.,Petsko, G.A.,Ringe, D.
Crystal structure of Saccharomyces cerevisiae cytosolic aspartate aminotransferase.
Protein Sci., 7:1380-1387, 1998

PubMed Abstract: The crystal structure of Saccharomyces cerevisiae cytoplasmic aspartate aminotransferase (EC 2.6.1.1) has been determined to 2.05 A resolution in the presence of the cofactor pyridoxal-5'-phosphate and the competitive inhibitor maleate. The structure was solved by the method of molecular replacement. The final value of the crystallographic R-factor after refinement was 23.1% with good geometry of the final model. The yeast cytoplasmic enzyme is a homodimer with two identical active sites containing residues from each subunit. It is found in the "closed" conformation with a bound maleate inhibitor in each active site. It shares the same three-dimensional fold and active site residues as the aspartate aminotransferases from Escherichia coli, chicken cytoplasm, and chicken mitochondria, although it shares less than 50% sequence identity with any of them. The availability of four similar enzyme structures from distant regions of the evolutionary tree provides a measure of tolerated changes that can arise during millions of years of evolution.

PubMed: 9655342

Experimental method

X-RAY DIFFRACTION (2.05 Å)