TY - JOUR
T1 - The agr inhibitors solonamide B and analogues alter immune responses to Staphylococccus aureus but do not exhibit adverse effects on immune cell functions
AU - Baldry, Mara
AU - Kitir, Betül
AU - Frøkiær, Hanne
AU - Christensen, Simon B.
AU - Taverne, Nico
AU - Meijerink, Marjolein
AU - Franzyk, Henrik
AU - Olsen, Christian Adam
AU - Wells, Jerry M.
AU - Ingmer, Hanne
PY - 2016/1/5
Y1 - 2016/1/5
N2 - Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-Associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed as an alternative approach to treat multi-drug resistant pathogens. One interesting anti-virulence target is the agr quorum-sensing system, which regulates virulence of CA-MRSA in response to agr-encoded autoinducing peptides. Agr regulation confines exotoxin production to the stationary growth phase with concomitant repression of surfaceexpressed adhesins. Solonamide B, a non-ribosomal depsipeptide of marine bacterial origin, was recently identified as a putative anti-virulence compound that markedly reduced expression of ?-hemolysin and phenol-solublemodulins. To further strengthen solonamide anti-virulence candidacy, we report the chemical synthesis of solonamide analogues, investigation of structure-function relationships, and assessment of their potential tomodulate immune cell functions. We found that structural differences between solonamide analogues confer significant differences in interference with agr, while immune cell activity and integrity is generally not affected. Furthermore, treatment of S. aureus with selected solonamides was found to only marginally influence the interaction with fibronectin and biofilm formation, thus addressing the concern that application of compounds inducing an agr-negative state may have adverse interactions with host factors in favor of host colonization.
AB - Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-Associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed as an alternative approach to treat multi-drug resistant pathogens. One interesting anti-virulence target is the agr quorum-sensing system, which regulates virulence of CA-MRSA in response to agr-encoded autoinducing peptides. Agr regulation confines exotoxin production to the stationary growth phase with concomitant repression of surfaceexpressed adhesins. Solonamide B, a non-ribosomal depsipeptide of marine bacterial origin, was recently identified as a putative anti-virulence compound that markedly reduced expression of ?-hemolysin and phenol-solublemodulins. To further strengthen solonamide anti-virulence candidacy, we report the chemical synthesis of solonamide analogues, investigation of structure-function relationships, and assessment of their potential tomodulate immune cell functions. We found that structural differences between solonamide analogues confer significant differences in interference with agr, while immune cell activity and integrity is generally not affected. Furthermore, treatment of S. aureus with selected solonamides was found to only marginally influence the interaction with fibronectin and biofilm formation, thus addressing the concern that application of compounds inducing an agr-negative state may have adverse interactions with host factors in favor of host colonization.
U2 - 10.1371/journal.pone.0145618
DO - 10.1371/journal.pone.0145618
M3 - Journal article
C2 - 26731096
SN - 1932-6203
VL - 11
JO - P L o S One
JF - P L o S One
IS - 1
M1 - e0145618
ER -