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Polynucleotide phosphorylase is a global regulator of virulence and persistency in Salmonella enterica.

ABSTRACT: For many pathogens, the ability to regulate their replication in host cells is a key element in establishing persistency. Here, we identified a single point mutation in the gene for polynucleotide phosphorylase (PNPase) as a factor affecting bacterial invasion and intracellular replication, and which determines the alternation between acute or persistent infection in a mouse model for Salmonella enterica infection. In parallel, with microarray analysis, PNPase was found to affect the mRNA levels of a subset of virulence genes, in particular those contained in Salmonella pathogenicity islands 1 and 2. The results demonstrate a connection between PNPase and Salmonella virulence and show that alterations in PNPase activity could represent a strategy for the establishment of persistency.

SUBMITTER: Clements MO

PROVIDER: S-EPMC124376 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature

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Polynucleotide phosphorylase is a global regulator of virulence and persistency in Salmonella enterica.

Clements Mark O MO Eriksson Sofia S Thompson Arthur A Lucchini Sacha S Hinton Jay C D JC Normark Staffan S Rhen Mikael M

Proceedings of the National Academy of Sciences of the United States of America 20020618 13

For many pathogens, the ability to regulate their replication in host cells is a key element in establishing persistency. Here, we identified a single point mutation in the gene for polynucleotide phosphorylase (PNPase) as a factor affecting bacterial invasion and intracellular replication, and which determines the alternation between acute or persistent infection in a mouse model for Salmonella enterica infection. In parallel, with microarray analysis, PNPase was found to affect the mRNA levels ...[more]

PMID: 12072563

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