Biofilm Formation and Motility Are Promoted by Cj0588-Directed Methylation of rRNA in .
Agnieszka Sałamaszyńska-Guz, Simon Rose, Claus A Lykkebo, Bartłomiej Taciak, Paweł Bącal, Tomasz Uśpieński, Stephen Douthwaite
Author Information
Agnieszka Sałamaszyńska-Guz: Division of Microbiology, Department of Pre-Clinical Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
Simon Rose: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
Claus A Lykkebo: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
Bartłomiej Taciak: Division of Physiology, Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
Paweł Bącal: Laboratory of Theory and Applications of Electrodes, Faculty of Chemistry, University of Warsaw, Warsaw, Poland.
Tomasz Uśpieński: Division of Microbiology, Department of Pre-Clinical Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
Stephen Douthwaite: Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
Numerous bacterial pathogens express an ortholog of the enzyme TlyA, which is an rRNA 2'--methyltransferase associated with resistance to cyclic peptide antibiotics such as capreomycin. Several other virulence traits have also been attributed to TlyA, and these appear to be unrelated to its methyltransferase activity. The bacterial pathogen possesses the TlyA homolog Cj0588, which has been shown to contribute to virulence. Here, we investigate the mechanism of Cj0588 action and demonstrate that it is a type I homolog of TlyA that 2'--methylates 23S rRNA nucleotide C1920. This same specific function is retained by Cj0588 both and also when expressed in . Deletion of the gene in or substitution with alanine of K, D, or K in the catalytic center of the enzyme cause complete loss of 2'--methylation activity. Cofactor interactions remain unchanged and binding affinity to the ribosomal substrate is only slightly reduced, indicating that the inactivated proteins are folded correctly. The substitution mutations thus dissociate the 2'--methylation function of Cj0588/TlyA from any other putative roles that the protein might play. strains expressing catalytically inactive versions of Cj0588 have the same phenotype as -null mutants, and show altered tolerance to capreomycin due to perturbed ribosomal subunit association, reduced motility and impaired ability to form biofilms. These functions are reestablished when methyltransferase activity is restored and we conclude that the contribution of Cj0588 to virulence in is a consequence of the enzyme's ability to methylate its rRNA.
