Analysis of the genomic plasticity of hybrid pathogenic E. coli of serotype O3:H2 and influence on their pathogenicity

• Grant number: 24/18627-4
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Rodrigo Tavanelli Hernandes
• Grantee: Daiany Ribeiro Paz de Lira
• Supervisor: Ulrich Dobrindt
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Institution abroad: University of Munster, Germany
• Associated to the scholarship: 22/08132-2 - Exploring the pathogenic metamorphosis of Escherichia coli of serotype O3:H2 associated with human infections, BP.DR

Abstract

Although described as diarrheagenic Escherichia coli, several studies in the literature are accumulating evidence that enteroaggregative E. coli (EAEC) isolates can be associated with extraintestinal infections, such as bacteremia and urinary tract infections. Here we analyzed the presence of the five extraintestinal pathogenic E. coli (ExPEC) classificatory genes (papA and/or papC, afa/dra, sfa/foc, kpsMTII, and iutA), that indicates the intrinsic potential of E. coli isolates to cause extraintestinal infections in healthy individuals, in a collection of 26 EAEC isolates of serotype O3:H2 (22 from stool and 4 from urine). This investigation showed that these genes were found in five distinct combinations. We selected one representative isolate (UPEC34), with the highest number of the classificatory ExPEC genes, and performed short and long read sequencing. This analysis showed that the pap, iutA, kpsMTII and afaBC genes are co-located in a single pathogenicity island (PAI) with similarity to PAICFT073-pheV (ICFT073) located in the chromosome. This PAI is 159.2 kb in length, comprises 156 coding sequences and harbors several virulence factor-encoding genes generally present in ExPEC isolates. The main objective of the present study is to investigate the genomic plasticity of the PAI I-CFT073-pheV (ICFT073)-like island found in the ExPEC/EAEC hybrid isolates from the serotype O3:H2, and to unveil how the gain or loss of some of the virulence factor-encoding genes from this PAI affects the pathogenicity of these hybrids in causing extraintestinal infection.