Genetic diversity, mobilisation and spread of the yersiniabactin-encoding mobile element ICEKp in Klebsiella pneumoniae populations
Mobile genetic elements (MGEs) that frequently transfer within and between bacterial species play a critical role in bacterial evolution, and often carry key accessory genes that associate with a bacteria’s ability to cause disease. MGEs carrying antimicrobial resistance (AMR) and/or virulence deter...
Saved in:
| Published in: | Microbial genomics Vol. 4; no. 9 |
|---|---|
| Main Authors: | , , , , , , , |
| Format: | Journal Article |
| Language: | English |
| Published: |
England
Microbiology Society
01.09.2018
|
| Subjects: | |
| ISSN: | 2057-5858, 2057-5858 |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Mobile genetic elements (MGEs) that frequently transfer within and between bacterial species play a critical role in bacterial evolution, and often carry key accessory genes that associate with a bacteria’s ability to cause disease. MGEs carrying antimicrobial resistance (AMR) and/or virulence determinants are common in the opportunistic pathogen
Klebsiella pneumoniae
, which is a leading cause of highly drug-resistant infections in hospitals. Well-characterised virulence determinants in
K. pneumoniae
include the polyketide synthesis loci
ybt
and
clb
(also known as
pks
), encoding the iron-scavenging siderophore yersiniabactin and genotoxin colibactin, respectively. These loci are located within an MGE called ICE
Kp
, which is the most common virulence-associated MGE of
K. pneumoniae,
providing a mechanism for these virulence factors to spread within the population. Here we apply population genomics to investigate the prevalence, evolution and mobility of
ybt
and
clb
in
K. pneumoniae
populations through comparative analysis of 2498 whole-genome sequences. The
ybt
locus was detected in 40 % of
K. pneumoniae
genomes, particularly amongst those associated with invasive infections. We identified 17 distinct
ybt
lineages and 3
clb
lineages, each associated with one of 14 different structural variants of ICE
Kp
. Comparison with the wider population of the family
Enterobacteriaceae
revealed occasional ICE
Kp
acquisition by other members. The
clb
locus was present in 14 % of all
K. pneumoniae
and 38.4 % of
ybt
+ genomes. Hundreds of independent ICE
Kp
integration events were detected affecting hundreds of phylogenetically distinct
K. pneumoniae
lineages, including at least 19 in the globally-disseminated carbapenem-resistant clone CG258. A novel plasmid-encoded form of
ybt
was also identified, representing a new mechanism for
ybt
dispersal in
K. pneumoniae
populations. These data indicate that MGEs carrying
ybt
and
clb
circulate freely in the
K. pneumoniae
population, including among multidrug-resistant strains, and should be considered a target for genomic surveillance along with AMR determinants. |
|---|---|
| Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
| ISSN: | 2057-5858 2057-5858 |
| DOI: | 10.1099/mgen.0.000196 |