TY - JOUR
T1 - Inhibition of Virulence Gene Expression in Staphylococcus aureus by Novel Depsipeptides from a Marine Photobacterium
AU - Månsson, Maria
AU - Nielsen, Anita
AU - Kjærulff, Louise
AU - Gotfredsen, Charlotte Held
AU - Wietz, Matthias
AU - Ingmer, Hanne
AU - Gram, Lone
AU - Larsen, Thomas Ostenfeld
PY - 2011
Y1 - 2011
N2 - During a global research expedition, more than five hundred marine bacterial
strains capable of inhibiting the growth of pathogenic bacteria were collected. The purpose
of the present study was to determine if these marine bacteria are also a source of
compounds that interfere with the agr quorum sensing system that controls virulence gene
expression in Staphylococcus aureus. Using a gene reporter fusion bioassay, we recorded agr
interference as enhanced expression of spa, encoding Protein A, concomitantly with reduced
expression of hla, encoding α-hemolysin, and rnaIII encoding RNAIII, the effector molecule
of agr. A marine Photobacterium produced compounds interfering with agr in S. aureus
strain 8325-4, and bioassay-guided fractionation of crude extracts led to the isolation of
two novel cyclodepsipeptides, designated solonamide A and B. Northern blot analysis
confirmed the agr interfering activity of pure solonamides in both S. aureus strain 8325-4
and the highly virulent, community-acquired strain USA300 (CA-MRSA). To our
knowledge, this is the first report of inhibitors of the agr system by a marine bacterium.
AB - During a global research expedition, more than five hundred marine bacterial
strains capable of inhibiting the growth of pathogenic bacteria were collected. The purpose
of the present study was to determine if these marine bacteria are also a source of
compounds that interfere with the agr quorum sensing system that controls virulence gene
expression in Staphylococcus aureus. Using a gene reporter fusion bioassay, we recorded agr
interference as enhanced expression of spa, encoding Protein A, concomitantly with reduced
expression of hla, encoding α-hemolysin, and rnaIII encoding RNAIII, the effector molecule
of agr. A marine Photobacterium produced compounds interfering with agr in S. aureus
strain 8325-4, and bioassay-guided fractionation of crude extracts led to the isolation of
two novel cyclodepsipeptides, designated solonamide A and B. Northern blot analysis
confirmed the agr interfering activity of pure solonamides in both S. aureus strain 8325-4
and the highly virulent, community-acquired strain USA300 (CA-MRSA). To our
knowledge, this is the first report of inhibitors of the agr system by a marine bacterium.
U2 - 10.3390/md9122537
DO - 10.3390/md9122537
M3 - Journal article
C2 - 22363239
SN - 1660-3397
SP - 2537.2552
JO - Marine Drugs
JF - Marine Drugs
IS - 9
ER -
