The irp2 and fyuA genes in High Pathogenicity Islands are involved in the pathogenesis of infections caused by avian pathogenic Escherichia coli (APEC)

Abstract

Avian pathogenic Escherichia coli (APEC) is a major bacterial infectious disease that may lead to local or systemic infections in chickens with clinical manifestations. The irp2-fyuA gene cluster has been confirmed to be the main genes involved in the synthesis of HPI. The objective of this study was to determine the influence of the irp2 and fyuA genes in the high pathogenicity island (HPI) of avian pathogenic Escherichia coli (APEC) on its pathogenicity by knocking out these genes. The ΔAE17 (lacking irp2) and ΔΔAE17 (lacking irp2 and fyuA) strains of APEC were constructed. The ΔAE17 and ΔΔAE17 strains showed significantly impaired capacity to adhere onto DF-1 cells. The LD 50 results indicated that the virulence of the ΔAE17 and ΔΔAE17 strains was decreased in comparison with that of the AE17 strain. We concluded that the knock-out of the core HPI genes weakened APEC adhesion onto DF-1 cells, inhibited transcription of virulence genes, and reduced pathogenicity in chicks. The effects of genetic deletion of irp2 and fyuA on APEC were more severe than those produced by deletion of irp2 only, indicating that irp2 and fyuA co-regulate APEC pathogenicity.

Development of three multiplex-PCR assays for virulence profiling of different iron acquisition systems in Escherichia coli

“…In the present study, the genes involved in iron acquisition via yersiniabactin siderophore ( fyuA and irp2) were prevalent in APEC isolates which may reflect the key role of yersiniabactin in pathogenesis of APEC strains as other studies have shown (31). Furthermore, in this study, the genes sitA and chuA were significantly prevalent in isolates recovered from poultry and human.…”

Carbapenemase-Producing Klebsiella pneumoniae From Transplanted Patients in Brazil: Phylogeny, Resistome, Virulome and Mobile Genetic Elements Harboring blaKPC–2 or blaNDM–1

“…The three virulence features included in yersiniabactin loci, ybtAEPQSTUX , siderophore genes, and yersiniabactin receptor, were detected in isolates of outbreaks A and C, and in all isolates of outbreak D, yersiniabactin loci lack yersiniabactin receptor and irp1 gene, which could reduce the biosynthesis and expression of yersiniabactin, the adherence capability, and the pathogenicity of these isolates ( Pelludat et al, 1998 ; Tu et al, 2016 ). The yersiniabactin cluster enables the scavenging of iron from host transport proteins, thus enhancing the ability of bacteria to replicate within the host and survive, and is mostly related to invasive infections ( Holden and Bachman, 2015 ).…”

Virulence and transcriptome profile of multidrug-resistant Escherichia coli from chicken

“…For this purpose, nine important DEGs were selected from isolate E. coli 381: NlpD , BssR , hha , MdtF , mdtG , FicC , DR76_RS08135, ImpG , RelE , and CspB . DNA polymerase III subunit alpha ( dnaE ) was used as a reference gene, and RT-qPCR was performed as described previously 108 . The sequence of primers used in RT-qPCR is included in Supplementary Table 4 .…”