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Phylogenetic barriers to horizontal transfer of antimicrobial peptide resistance genes in the human gut microbiota.

ABSTRACT: The human gut microbiota has adapted to the presence of antimicrobial peptides (AMPs), which are ancient components of immune defence. Despite its medical importance, it has remained unclear whether AMP resistance genes in the gut microbiome are available for genetic exchange between bacterial species. Here, we show that AMP resistance and antibiotic resistance genes differ in their mobilization patterns and functional compatibilities with new bacterial hosts. First, whereas AMP resistance genes are widespread in the gut microbiome, their rate of horizontal transfer is lower than that of antibiotic resistance genes. Second, gut microbiota culturing and functional metagenomics have revealed that AMP resistance genes originating from phylogenetically distant bacteria have only a limited potential to confer resistance in Escherichia coli, an intrinsically susceptible species. Taken together, functional compatibility with the new bacterial host emerges as a key factor limiting the genetic exchange of AMP resistance genes. Finally, our results suggest that AMPs induce highly specific changes in the composition of the human microbiota, with implications for disease risks.

SUBMITTER: Kintses B

PROVIDER: S-EPMC6387620 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Phylogenetic barriers to horizontal transfer of antimicrobial peptide resistance genes in the human gut microbiota.

Kintses Bálint B Méhi Orsolya O Ari Eszter E Számel Mónika M Györkei Ádám Á Jangir Pramod K PK Nagy István I Pál Ferenc F Fekete Gergely G Tengölics Roland R Nyerges Ákos Á Likó István I Bálint Anita A Molnár Tamás T Bálint Balázs B Vásárhelyi Bálint Márk BM Bustamante Misshelle M Papp Balázs B Pál Csaba C

Nature microbiology 20181217 3

The human gut microbiota has adapted to the presence of antimicrobial peptides (AMPs), which are ancient components of immune defence. Despite its medical importance, it has remained unclear whether AMP resistance genes in the gut microbiome are available for genetic exchange between bacterial species. Here, we show that AMP resistance and antibiotic resistance genes differ in their mobilization patterns and functional compatibilities with new bacterial hosts. First, whereas AMP resistance genes ...[more]

PMID: 30559406

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Dataset Information

Phylogenetic barriers to horizontal transfer of antimicrobial peptide resistance genes in the human gut microbiota.

Publications

Phylogenetic barriers to horizontal transfer of antimicrobial peptide resistance genes in the human gut microbiota.

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