Negative frequency-dependent selection and asymmetrical transformation stabilise multi-strain bacterial population structures.
Journal
The ISME journal
ISSN: 1751-7370
Titre abrégé: ISME J
Pays: England
ID NLM: 101301086
Informations de publication
Date de publication:
05 2021
05 2021
Historique:
received:
11
06
2020
accepted:
03
12
2020
revised:
01
12
2020
pubmed:
8
1
2021
medline:
3
6
2021
entrez:
7
1
2021
Statut:
ppublish
Résumé
Streptococcus pneumoniae can be divided into many strains, each a distinct set of isolates sharing similar core and accessory genomes, which co-circulate within the same hosts. Previous analyses suggested the short-term vaccine-associated dynamics of S. pneumoniae strains may be mediated through multi-locus negative frequency-dependent selection (NFDS), which maintains accessory loci at equilibrium frequencies. Long-term simulations demonstrated NFDS stabilised clonally-evolving multi-strain populations through preventing the loss of variation through drift, based on polymorphism frequencies, pairwise genetic distances and phylogenies. However, allowing symmetrical recombination between isolates evolving under multi-locus NFDS generated unstructured populations of diverse genotypes. Replication of the observed data improved when multi-locus NFDS was combined with recombination that was instead asymmetrical, favouring deletion of accessory loci over insertion. This combination separated populations into strains through outbreeding depression, resulting from recombinants with reduced accessory genomes having lower fitness than their parental genotypes. Although simplistic modelling of recombination likely limited these simulations' ability to maintain some properties of genomic data as accurately as those lacking recombination, the combination of asymmetrical recombination and multi-locus NFDS could restore multi-strain population structures from randomised initial populations. As many bacteria inhibit insertions into their chromosomes, this combination may commonly underlie the co-existence of strains within a niche.
Identifiants
pubmed: 33408365
doi: 10.1038/s41396-020-00867-w
pii: 10.1038/s41396-020-00867-w
pmc: PMC8115253
doi:
Types de publication
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
1523-1538Subventions
Organisme : NIAID NIH HHS
ID : R01 AI106786
Pays : United States
Organisme : European Research Council
ID : 742158
Pays : International
Organisme : Wellcome Trust
ID : 104169/Z/14/A
Pays : United Kingdom
Organisme : NIGMS NIH HHS
ID : U54 GM088558
Pays : United States
Organisme : Wellcome Trust
Pays : United Kingdom
Organisme : NIGMS NIH HHS
ID : U54GM088558
Pays : United States
Organisme : Medical Research Council
ID : MR/R015600/1
Pays : United Kingdom
Organisme : Medical Research Council
ID : MR/T016434/1
Pays : United Kingdom
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