9IGK

Crystal structure of P. syringae phosphinothricin acetyltransferase PSPTO_3321

Summary for 9IGK

• Entry DOI: 10.2210/pdb9igk/pdb
• Descriptor: Phosphinothricin N-acetyltransferase, CITRIC ACID, DI(HYDROXYETHYL)ETHER, ... (6 entities in total)
• Functional Keywords: acetyltransferase, phosphinothricin, transferase
• Biological source: Pseudomonas syringae pv. tomato str. DC3000
• Total number of polymer chains: 4
• Total formula weight: 80452.07

Authors

Davies, A.M.,Trentham, D.,Sutton, B.J.,Brown, P.R. (deposition date: 2025-02-19, release date: 2025-03-12, Last modification date: 2025-03-19)

Primary citation

Davies, A.M.,Trentham, D.,Sutton, B.J.,Brown, P.R.
Structure and activity of a phosphinothricin N-acetyltransferase (PSPTO_3321) from Pseudomonas syringae pv. tomato DC3000.
Biochem.Biophys.Res.Commun., 755:151539-151539, 2025

PubMed Abstract: Phosphinothricin inhibits plant glutamine synthetase and is used as a herbicide. Streptomyces hygroscopicus and Streptomyces viridochromogenes, which produce phosphinothricin naturally, encode acetyltransferases that confer phosphinothricin resistance. In the Pseudomonas genome database, a number of proteins have been annotated as phosphinothricin acetyltransferases and putative phosphinothricin acetyltransferases. One such protein is PSPTO_3321 from P. syringae, a strain that causes tomato speck. Here, we reveal that PSPTO_3321 from P. syringae, termed syr_pat, is a phosphinothricin acetyltransferase, and also retains a lower level of activity against the structurally similar substrate methionine sulfoximine. We solved a 1.6 Å resolution crystal structure of syr_pat alone and a 2.5 Å resolution structure for a complex with -phosphinothricin. We also characterised active site mutants, providing insights into substrate specificity. Our work now provides a basis for further study of the reaction mechanism.

PubMed: 40054337
DOI: 10.1016/j.bbrc.2025.151539

Experimental method

X-RAY DIFFRACTION (1.6 Å)