Characterization of the DsbA oxidative folding catalyst from Pseudomonas aeruginosa reveals a highly oxidizing protein that binds small molecules.
Bacterial antibiotic resistance is an emerging global crisis, and treatment of multidrug-resistant gram-negative infections, particularly those caused by the opportunistic human pathogen Pseudomonas aeruginosa, remains a major challenge. This problem is compounded by a lack of new antibiotics in the development pipeline: only two new classes have been developed since the 1960s, and both are indicated for multidrug-resistant gram-positive infections. A promising new approach to combat antibiotic resistance is by targeting bacterial virulence, rather than bacterial viability. The bacterial periplasmic protein DsbA represents a central point for antivirulence intervention because its oxidoreductase activity is essential for the folding and function of almost all exported virulence factors. Here we describe the three-dimensional structure of this DsbA target from P. aeruginosa, and we establish for the first time that a member of this enzyme family is capable of binding small molecules. We also describe biochemical assays that validate the redox activity of PaDsbA. Together, the structural and functional characterization of PaDsbA provides the basis for future studies aimed at designing a new class of antivirulence compounds to combat antibiotic-resistant P. aeruginosa infection.
The University of Queensland, Institute for Molecular Bioscience , Division of Chemistry and Structural Biology, Brisbane, Queensland, Australia.
Stephen R
SR
Shouldice
Begoña
B
Heras
Russell
R
Jarrott
Pooja
P
Sharma
Martin J
MJ
Scanlon
Jennifer L
JL
Martin
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D005816:Genetic Complementation Test; D005990:Glycerol / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D019704:Protein Disulfide-Isomerases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D016415:Sequence Alignment; D037521:Virulence Factors / Q000737:chemistry* / Q000378:metabolism
D001426:Bacterial Proteins; D007328:Insulin; D037521:Virulence Factors; D010088:Oxidoreductases; D019704:Protein Disulfide-Isomerases; D005990:Glycerol