2025/09/30 by Allison K. Guitor, Shuai Wang, Owen T. Tuck +15 · 1 voice · 1 citation
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Antibiotic Resistance in Bacteria #Bacterial genetics #Coding region #ENCODE #Enterobacteriaceae and Cronobacter Research #Gene #Genome #Host (biology) #Plasmid #Probiotics and Fermented Foods #Sequence (biology)
paper · pdf · doi:10.1101/2025.09.30.679422
published in bioRxiv (Cold Spring Harbor Laboratory) (Cold Spring Harbor Laboratory)
openalex publication_date 2025/09/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Summary Humans and animals are ubiquitously colonized by Enterobacteriaceae , a bacterial family that contains both commensals and clinically significant pathogens. Here, we report Enterobacteriaceae megaplasmids of up to 1.58 Mbp in length in infant and adult guts, and other microbiomes. Of 19 complete plasmid genomes, one was reconstructed from an E. coli isolate; others were linked to species of Citrobacter and Enterobacter via analysis of genome modification patterns. The detection of related plasmids in different Enterobacteriaceae , conjugation machinery, and more diverse modified motifs in certain plasmids compared to hosts suggests that these elements are self-transmissible, with a broad host range. The plasmids encode multi-drug efflux systems and potential secreted effectors. Up to 208 tRNAs are encoded and include sequence variants that may counter tRNA-centric defense mechanisms. Overall, the vast megaplasmid coding capacity may broaden host range, increase competitiveness, control invasion by other elements, and counter programmed cell death.