Download MendeleyStructure and function of the pyridoxal 5'-phosphate-dependent (PLP) threonine deaminase IlvA1 from Pseudomonas aeruginosa PAO1.
Jia, H., Chen, Y., Chen, Y., Liu, R., Zhang, Q., Bartlam, M.(2024) Biochem Biophys Res Commun 704: 149710-149710
- PubMed: 38417345
- DOI: https://doi.org/10.1016/j.bbrc.2024.149710
- Primary Citation of Related Structures:
8Y1J - PubMed Abstract:
IlvA1, a pyridoxal phosphate-dependent (PLP) enzyme, catalyzes the deamination of l-threonine and l-serine to yield 2-ketobutyric acid or pyruvate. To gain insights into the function of IlvA1, we determined its crystal structure from Pseudomonas aeruginosa to 2.3 Å. Density for a 2-ketobutyric acid product was identified in the active site and a putative allosteric site. Activity and substrate binding assays confirmed that IlvA1 utilizes l-threonine, l-serine, and L-allo-threonine as substrates. The enzymatic activity is regulated by the end products l-isoleucine and l-valine. Additionally, the efficiency of d-cycloserine and l-cycloserine inhibitors on IlvA1 enzymatic activity was examined. Notably, site-directed mutagenesis confirmed the active site residues and revealed that Gln165 enhances the enzyme activity, emphasizing its role in substrate access. This work provides crucial insights into the structure and mechanism of IlvA1 and serves as a starting point for further functional and mechanistic studies of the threonine deaminase in P. aeruginosa.
Organizational Affiliation:
State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, and College of Life Sciences, Nankai University, Tianjin, 300071, China; Chinese Academy of Medical Sciences & Peking Union Medical College (State Key Laboratory of Bioactive Substance and Function of Natural Medicines & NHC Key Laboratory of Biosynthesis of Natural Products), Institute of Materia Medica, Beijing, 100050, China.
