Diversity and population overlap between avian and human Escherichia coli belonging to sequence type 95

TY - JOUR

T1 - Diversity and population overlap between avian and human Escherichia coli belonging to sequence type 95

AU - Jørgensen, Steffen L.

AU - Stegger, Marc

AU - Kudirkiene, Eglé

AU - Lilje, Berit

AU - Poulsen, Louise L.

AU - Ronco, Troels

AU - Dos Santos, Teresa Pires

AU - Kiil, Kristoffer

AU - Bisgaard, Magne

AU - Pedersen, Karl

AU - Nolan, Lisa K.

AU - Price, Lance B.

AU - Olsen, Rikke H.

AU - Andersen, Paal S.

AU - Christensen, Henrik

PY - 2019

Y1 - 2019

N2 - Avian-pathogenic Escherichia coli (APEC) is a subgroup of extraintestinal pathogenic E. coli (ExPEC) presumed to be zoonotic and to represent an external reservoir for extraintestinal infections in humans, including uropathogenic E. coli (UPEC) causing urinary tract infections. Comparative genomics has previously been applied to investigate whether APEC and human ExPEC are distinct entities. Even so, whole-genome-based studies are limited, and large-scale comparisons focused on single sequence types (STs) are not available yet. In this study, comparative genomic analysis was performed on 323 APEC and human ExPEC genomes belonging to sequence type 95 (ST95) to investigate whether APEC and human ExPEC are distinct entities. Our study showed that APEC of ST95 did not constitute a unique ExPEC branch and was genetically diverse. A large genetic overlap between APEC and certain human ExPEC was observed, with APEC located on multiple branches together with closely related human ExPEC, including nearly identical APEC and human ExPEC. These results illustrate that certain ExPEC clones may indeed have the potential to cause infection in both poultry and humans. Previously described ExPEC-associated genes were found to be encoded on ColV plasmids. These virulence-associated plasmids seem to be crucial for ExPEC strains to cause avian colibacillosis and are strongly associated with strains of the mixed APEC/ human ExPEC clusters. The phylogenetic analysis revealed two distinct branches consisting of exclusively closely related human ExPEC which did not carry the virulence-associated plasmids, emphasizing a lower avian virulence potential of human ExPEC in relation to an avian host.

AB - Avian-pathogenic Escherichia coli (APEC) is a subgroup of extraintestinal pathogenic E. coli (ExPEC) presumed to be zoonotic and to represent an external reservoir for extraintestinal infections in humans, including uropathogenic E. coli (UPEC) causing urinary tract infections. Comparative genomics has previously been applied to investigate whether APEC and human ExPEC are distinct entities. Even so, whole-genome-based studies are limited, and large-scale comparisons focused on single sequence types (STs) are not available yet. In this study, comparative genomic analysis was performed on 323 APEC and human ExPEC genomes belonging to sequence type 95 (ST95) to investigate whether APEC and human ExPEC are distinct entities. Our study showed that APEC of ST95 did not constitute a unique ExPEC branch and was genetically diverse. A large genetic overlap between APEC and certain human ExPEC was observed, with APEC located on multiple branches together with closely related human ExPEC, including nearly identical APEC and human ExPEC. These results illustrate that certain ExPEC clones may indeed have the potential to cause infection in both poultry and humans. Previously described ExPEC-associated genes were found to be encoded on ColV plasmids. These virulence-associated plasmids seem to be crucial for ExPEC strains to cause avian colibacillosis and are strongly associated with strains of the mixed APEC/ human ExPEC clusters. The phylogenetic analysis revealed two distinct branches consisting of exclusively closely related human ExPEC which did not carry the virulence-associated plasmids, emphasizing a lower avian virulence potential of human ExPEC in relation to an avian host.

KW - E. coli

KW - Genomics

KW - Pathogenicity

KW - Sequencing

KW - Zoonosis

U2 - 10.1128/mSphere.00333-18

DO - 10.1128/mSphere.00333-18

M3 - Journal article

C2 - 30651401

AN - SCOPUS:85060167821

SN - 2379-5042

VL - 4

JO - mSphere

JF - mSphere

IS - 1

M1 - e00333-18

ER -