The Association between Insertion Sequences and Antibiotic Resistance Genes

Area of Science:

• Microbiology
• Genomics
• Bioinformatics

Background:

• Antibiotic resistance genes (ARGs) are a major threat to public health.
• Insertion sequences (ISs) are mobile genetic elements that mobilize genes, including ARGs.
• Understanding IS-ARG associations can help discover novel ARGs.

Purpose of the Study:

• To comprehensively analyze the association of specific ISs with known ARGs.
• To identify ISs and their genomic contexts that are strongly associated with ARGs.
• To explore environments where ARG-associated ISs are abundant.

Main Methods:

• Analysis of a large collection of bacterial genomes (2,437 ARGs, 3,768 ISs).
• Characterization of the immediate genetic context surrounding ARGs and ISs.
• Analysis of 1,891 metagenomes to assess IS abundance in different environments.

Main Results:

• A subset of ISs and composite transposons showed significant associations with ARGs.
• Specific IS families (IS6, Tn3, IS4, IS1) were strongly linked to diverse ARGs and abundant in pathogens.
• Metagenomic analysis revealed similar ARG-IS associations as observed in genomes.

Conclusions:

• The context of specific ISs and composite transposons is valuable for discovering novel ARGs.
• Identifying IS-ARG relationships can guide the discovery of new ARGs and inform surveillance strategies.
• This research provides insights into the mobilization and transfer mechanisms of ARGs.