8R3N

Crystal structure of PfpI, Pseudomonas aeruginosa PAO1

Summary for 8R3N

• Entry DOI: 10.2210/pdb8r3n/pdb
• Descriptor: Protease PfpI (2 entities in total)
• Functional Keywords: glyoxalase, thij/dj-1/pfpi superfamily member, oxidoreductase
• Biological source: Pseudomonas aeruginosa
• Total number of polymer chains: 2
• Total formula weight: 38537.35

Authors

Grimm, L.,Wijaya, A.J. (deposition date: 2023-11-10, release date: 2025-03-19, Last modification date: 2025-04-09)

Primary citation

Grimm, L.,Wijaya, A.,Askenasy, I.,Nazeer, R.R.,Seki, H.,Brear, P.D.,Figueroa, W.,Spring, D.R.,Welch, M.
Pseudomonas aeruginosa PfpI is a methylglyoxalase.
J.Biol.Chem., 301:108374-108374, 2025

PubMed Abstract: Pseudomonas aeruginosa is an opportunistic pathogen, commonly associated with human airway infections. Based on its amino acid sequence similarity with Pyrococcus furiosusprotease I, P. aeruginosa PfpI was originally annotated as an intracellular protease. In this work, we show that PfpI is a methylglyoxalase. The X-ray crystal structure of the purified protein was solved to 1.4 Å resolution. The structural data indicated that PfpI shares the same constellation of active site residues (including the catalytic Cys112 and His113) as those seen in a well-characterized bacterial methylglyoxalase from Escherichia coli, YhbO. Using NMR, we confirmed that PfpI qualitatively converted methylglyoxal into lactic acid. Quantitation of lactate produced by the methylglyoxalase activity of PfpI yielded a k of 102 min and a K of 369 μM. Mutation of Cys112 and His113 in PfpI led to complete loss of methylglyoxalase activity. To investigate the functional impact of PfpI in vivo, a ΔpfpI deletion mutant was made. Quantitative proteomic analyses revealed a pattern of changes consistent with perturbation of ribosomal function, Zn limitation, C1 metabolism, and glutathione metabolism. These findings are consistent with PfpI being a glutathione-independent methylglyoxalase. Previously, transposon insertion (pfpI::Tn) mutants have been reported to exhibit phenotypes associated with antibiotic resistance, motility and the response to oxidative stress. However, the ΔpfpI mutant generated in this study displayed none of these phenotypes. Whole-genome sequencing of the previously described pfpI::Tn mutants revealed that they also contain a variety of other genetic changes that likely account for their observed phenotypes.

PubMed: 40043953
DOI: 10.1016/j.jbc.2025.108374

Experimental method

X-RAY DIFFRACTION (1.45 Å)