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. 1998 Jun;7(6):1380–1387. doi: 10.1002/pro.5560070614

Crystal structure of Saccharomyces cerevisiae cytosolic aspartate aminotransferase.

C J Jeffery 1, T Barry 1, S Doonan 1, G A Petsko 1, D Ringe 1
PMCID: PMC2144045  PMID: 9655342

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.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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