Peer-Reviewed Journal Details
Mandatory Fields
Rea, RB;Gahan, CGM;Hill, C
2004
February
Infection and Immunity
Disruption of putative regulatory loci in Listeria monocytogenes demonstrates a significant role for fur and PerR in virulence
Validated
WOS: 95 ()
Optional Fields
ACID TOLERANCE RESPONSE OXIDATIVE STRESS RESISTANCE FERRIC UPTAKE REGULATOR BACILLUS-SUBTILIS STAPHYLOCOCCUS-AUREUS TOPOISOMERASE-I GENE-EXPRESSION CLPC ATPASE IRON INFECTION
72
717
727
The ability to adapt to adverse environmental conditions encountered in food and during host infection is a sine qua non for a successful Listeria monocytogenes infection. This ability is likely to depend on complex regulatory pathways controlled by a number of key regulators. We utilized the pORI19 plasmid integration system to analyze the role of six putative regulatory loci in growth under suboptimal environmental conditions and during murine infection. Disruption of loci encoding a topoisomerase III (lmo2756), a putative methyltransferase (lmo0581), and a regulator of the MarR family (lmo1618) revealed roles for the methyltransferase and the MarR regulator in growth under environmental stress conditions. However, plasmid integration into these loci had no impact on virulence potential in the murine model of infection. Disruption of the alternative sigma factor Sigma-H resulted in a mutant that demonstrated reduced growth potential in minimal medium. Murine studies indicated a minor role for this sigma factor in the infectious process. Strikingly, disruption of both perR and fur loci resulted in mutants that are significantly affected in virulence for mice, with the fur mutant demonstrating the greatest reduction in virulence potential. Both perR and fur mutants demonstrated increased resistance to hydrogen peroxide and the fur mutant was sensitive to low-iron conditions. The virulence defect of both fur and perR mutants could be rescued by iron-overload after esculetin treatment of mice, suggesting that the in vivo role of these gene products is to procure iron for bacterial growth.
WASHINGTON
0019-9567
10.1128/IAI.72.2.717-727.2004
Grant Details