Type

Journal Article

Authors

Colin Hill
Cormac G M Gahan
Maire Begley
Sheila Ryan

Subjects

Microbiology

Topics
virulence gene expression profiling mice gene deletion drug effects gene expression regulation bacterial anaerobiosis reverse transcriptase polymerase chain reaction hydrogen ion concentration spleen microbial viability virulence factors listeriosis arginine deiminase pharmacology anti bacterial agents bacterial proteins hydrolases acids animals genetics microbiology metabolism listeria monocytogenes

Molecular characterization of the arginine deiminase system in Listeria monocytogenes: regulation and role in acid tolerance. (2009)

Abstract The capacity of Listeria monocytogenes to withstand low pH is important for growth in low-pH foods, successful passage through the gastric barrier and survival within the macrophage phagosome. The ability of this pathogen to survive and adapt to acidic conditions is therefore predicted to play a significant role in the infectious cycle. In silico analysis of the L. monocytogenes genome revealed the presence of putative arginine deiminase (ADI) genes, which have been shown to play a role in the acid tolerance of other bacterial genera. In the present study, we show that L. monocytogenes possesses a functional ADI system and analysis of deletion mutants reveals that it contributes to both growth and survival of the bacterium under acidic conditions. An RT-PCR approach demonstrated that expression of ADI genes is increased in environments of low pH and anaerobicity and in the presence of arginine. A putative activator of ADI genes, namely ArgR, was identified and was shown to contribute to transcriptional regulation at this locus. Furthermore, expression of ADI genes was shown to be modulated by both the alternative stress sigma factor sigma(B) and the central virulence regulator PrfA. Finally, using the murine model of infection, we have established a role for the ADI system in the virulence of L. monocytogenes.
Collections Ireland -> University College Cork -> PubMed

Full list of authors on original publication

Colin Hill, Cormac G M Gahan, Maire Begley, Sheila Ryan

Experts in our system

1
Colin Hill
University College Cork
Total Publications: 351
 
2
Cormac G M Gahan
University College Cork
Total Publications: 109
 
3
Maire Begley
University College Cork
Total Publications: 27