Inhibitory Evaluation of αPMM/PGM from <i>Pseudomonas aeruginosa</i>: Chemical Synthesis, Enzyme Kinetics, and Protein Crystallographic Study

Abstract

α-Phosphomannomutase/phosphoglucomutase (αPMM/PGM) from <i>P. aeruginosa</i> is involved in bacterial cell wall assembly and is implicated in <i>P. aeruginosa</i> virulence, yet few studies have addressed αPMM/PGM inhibition from this important Gram-negative bacterial human pathogen. Four structurally different α-d-glucopyranose 1-phosphate (αG1P) derivatives including 1-<i>C</i>-fluoromethylated analogues (<b>1</b>-<b>3</b>), 1,2-cyclic phosph(on)ate analogues (<b>4</b>-<b>6</b>), isosteric methylene phosphono analogues (<b>7</b> and <b>8</b>), and 6-fluoro-αG1P (<b>9</b>), were synthesized and assessed as potential time-dependent or reversible αPMM/PGM inhibitors. The resulting kinetic data were consistent with the crystallographic structures of the highly homologous <i>Xanthomonas citri</i> αPGM with inhibitors <b>3</b> and <b>7</b>-<b>9</b> binding to the enzyme active site (1.65-1.9 Å). These structural and kinetic insights will enhance the design of future αPMM/PGM inhibitors.