AUTHOR=Haddad Nabila , Tresse Odile , Rivoal Katell , Chevret Didier , Nonglaton Quentin , Burns Christopher M., Prévost Hervé , Cappelier Jean-Michel 

TITLE=Polynucleotide phosphorylase has an impact on cell biology of Campylobacter jejuni

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=2

YEAR=2012

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2012.00030

DOI=10.3389/fcimb.2012.00030

ISSN=2235-2988

ABSTRACT=<p>Polynucleotide phosphorylase (PNPase), encoded by the <italic>pnp</italic> gene, is known to degrade mRNA, mediating post-transcriptional regulation and may affect cellular functions. The role of PNPase is pleiotropic. As orthologs of the two major ribonucleases (RNase E and RNase II) of <italic>Escherichia coli</italic> are missing in the <italic>Campylobacter jejuni</italic> genome, in the current study the focus has been on the <italic>C. jejuni</italic> ortholog of PNPase. The effect of PNPase mutation on <italic>C. jejuni</italic> phenotypes and proteome was investigated. The inactivation of the <italic>pnp</italic> gene reduced significantly the ability of <italic>C. jejuni</italic> to adhere and to invade Ht-29 cells. Moreover, the <italic>pnp</italic> mutant strain exhibited a decrease in <italic>C. jejuni</italic> swimming ability and chick colonization. To explain effects of PNPase on <italic>C. jejuni</italic> 81-176 phenotype, the proteome of the <italic>pnp</italic> mutant and parental strains were compared. Overall, little variation in protein production was observed. Despite the predicted role of PNPase in mRNA regulation, the <italic>pnp</italic> mutation did not induce profound proteomic changes suggesting that other ribonucleases in <italic>C. jejuni</italic> might ensure this biological function in the absence of PNPase. Nevertheless, synthesis of proteins which are involved in virulence (LuxS, PEB3), motility (<italic>N</italic>-acetylneuraminic acid synthetase), stress-response (KatA, DnaK, Hsp90), and translation system (EF-Tu, EF-G) were modified in the <italic>pnp</italic> mutant strain suggesting a more specific role of PNPase in <italic>C. jejuni.</italic> In conclusion, PNPase deficiency induces limited but important consequences on <italic>C. jejuni</italic> biology that could explain swimming limitation, chick colonization delay, and the decrease of cell adhesion/invasion ability.</p>