Correlation between biofilm formation and production of polysaccharide intercellular adhesin in clinical isolates of coagulase-negative staphylococci.
The ability to form a biofilm seems to play an essential role in the virulence of coagulase-negative staphylococci (CoNS) by permitting them to cause persistent prosthetic device-related infections. The most clearly characterized component of staphylococcal biofilms is the polysaccharide intercellular adhesin (PIA) encoded by the icaADBC operon. In the present paper, we assess the link between the ability to form a biofilm (Bf+/-), to synthesize PIA (PIA+/-) and the presence of the ica locus (ica+/-). For this purpose, 66 CoNS strains were tested in vitro. Seventy three percent of all strains revealed presence of the ica locus (ica+), and therefore were potentially able to produce PIA and to form a biofilm. However, the characteristics observed indicated that 15% of all strains were biofilm forming without PIA production (Bf+, PIA-, ica+/-) while 8% were PIA producers without biofilm formation (Bf-, PIA+, ica+). On the basis of the obtained data we conclude that (i) PIA synthesis alone is not sufficient to produce a biofilm and (ii) staphylococci can also form a biofilm without producing PIA.
Chokr
Ali
A
Laboratoire de Recherche sur les Biomatériaux et les Biotechnologies, Université du Littoral Côte d'Opale, Inserm-ERI 002, Bassin Napoléon, BP 120, F-62327 Boulogne sur mer, France.
Watier
Denis
D
Eleaume
Heïdy
H
Pangon
Béatrice
B
Ghnassia
Jean-Claude
JC
Mack
Dietrich
D
Jabbouri
Saïd
S
D018441:Biofilms / Q000254:growth & development*; D003030:Coagulase / Q000172:deficiency; D006801:Humans; D005810:Multigene Family; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D013203:Staphylococcal Infections / Q000382:microbiology*; D013210:Staphylococcus / Q000378:metabolism*; D013212:Staphylococcus epidermidis / Q000378:metabolism
D003030:Coagulase; D011135:Polysaccharides, Bacterial; C113579:polysaccharide intercellular adhesin