Identification of new genes associated with intermediate resistance of Enterococcus faecalis to divercin V41, a pediocin-like bacteriocin.
It has been suggested that resistance to class IIa bacteriocins occurs at either a low or a high level. In listerial strains, low-level resistance (2-4-fold) to class IIa bacteriocins is attributed to alterations in membrane lipid composition. In Listeria monocytogenes and Enterococcus faecalis, high-level resistance (1000-fold) correlates with inactivation of the mptACD operon, which encodes the EII(Man)(t) mannose permease of the phosphotransferase system (PTS). Previous studies reported that in L. monocytogenes, high-level resistance involved the sigma(54) factor and the ManR activator. In this investigation, three genes associated with the resistance of Ent. faecalis JH2-2 to divercin V41, a pediocin-like bacteriocin from Carnobacterium divergens V41, were clearly identified by screening an insertional mutant library of Ent. faecalis JH2-2. These genes correspond to the well-known rpoN gene, which encodes sigma(54) factor, and to genes encoding a glycerophosphoryl diester phosphodiesterase (GlpQ) and a protein with a putative phosphodiesterase function (PDE). Resistance of the three mutants defective in the aforementioned genes appeared to be graduated: the rpoN mutant was more resistant than the glpQ mutant, which was more resistant than the pde mutant. Moreover, this resistance was specific to class IIa bacteriocins.
Calvez
Ségolène
S
UMR-INRA 1014 SECALIM, ENITIAA, Rue de la Géraudière, BP 82225, Nantes Cedex 3, France.
Rincé
Alain
A
Laboratoire de Microbiologie de l'Environnement, EA 956, USC INRA 2017, IRBA, Université de Caen, Caen Cedex, France.
Auffray
Yanick
Y
Laboratoire de Microbiologie de l'Environnement, EA 956, USC INRA 2017, IRBA, Université de Caen, Caen Cedex, France.
Prévost
Hervé
H
UMR-INRA 1014 SECALIM, ENITIAA, Rue de la Géraudière, BP 82225, Nantes Cedex 3, France.
Drider
Djamel
D
UMR-INRA 1014 SECALIM, ENITIAA, Rue de la Géraudière, BP 82225, Nantes Cedex 3, France.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D001430:Bacteriocins / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000235:genetics*; D016254:Mutagenesis, Insertional; D010727:Phosphoric Diester Hydrolases / Q000235:genetics; D051877:RNA Polymerase Sigma 54 / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001430:Bacteriocins; C116372:divercin V41; D051877:RNA Polymerase Sigma 54; D010727:Phosphoric Diester Hydrolases; C087921:glpQ protein, Bacteria