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Comparison of wildtype and agrB-null mutant Type A Clostridium perfringens strain CP1

ABSTRACT: Clostridium perfringens encodes at least two different quorum sensing (QS) systems, the Agr-like and LuxS, and recent studies have highlighted their importance in the regulation of toxin production and virulence. The role of QS in the pathogenesis of necrotic enteritis (NE) in poultry and the regulation of NetB, the key toxin involved, has not yet been investigated. We have generated isogenic agrB-null and complemented strains from parent CP1, and demonstrated that the virulence of the agrB-null mutant was strongly attenuated in a chicken NE model system, and restored by complementation. The production of NetB, a key NE-associated toxin, was dramatically reduced in the agrB mutant at both the transcriptional and protein level, though not in a luxS mutant. Transwell assays confirmed that the Agr-like QS system controls NetB production through a diffusible signal. Global gene expression analysis of the agrB mutant identified additional genes modulated by Agr-like QS, including operons related to phospholipid metabolism and adherence, which may also play a role in NE pathogenesis. This study provides the first evidence that the Agr-like QS system is critical for NE pathogenesis, and identifies a number of Agr-regulated genes, most notably the NetB toxin, that are potentially involved in mediating its effects. The Agr-like QS system thus may serve as a target for developing novel interventions to prevent NE in chickens.

ORGANISM(S): Clostridium perfringens

PROVIDER: GSE97874 | GEO | 2017/04/18

SECONDARY ACCESSION(S): PRJNA383125

REPOSITORIES: GEO

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