A chromosome-encoded T4SS independently contributes to horizontal gene transfer in Enterococcus faecalis

• Published in: Cell reports (Cambridge) Vol. 41; no. 6; p. 111609
• Main Authors: Hua, Mingxi, Dai, Dongfa, Du, Pengcheng, Chen, Nan, Duan, Ang, Yue, Jinglin, Jia, Hongbing, Rong, Chengbo, Li, Ang, Zeng, Hui, Chen, Chen
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 08.11.2022
• Subjects: Enterococcus faecalis; HGT; horizontal gene transfer; ICEs; integrative and conjugative elements; multiple-drug resistance; secretion system; Enterococcus faecalis; HGT; CP: Microbiology; secretion system; ICEs; horizontal gene transfer; multiple-drug resistance; integrative and conjugative elements
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2022.111609

Bacterial type IV secretion systems (T4SSs) are the specific devices that mediate the dissemination of antibiotic resistant genes via horizontal gene transfer (HGT). Multi-drug-resistant Enterococcus faecalis (E. faecalis) represents a clinical public health threat because of its transferable plasmid with a functional plasmid-encoded (PE)-T4SS. Here, we report a chromosome-encoded (CE)-T4SS that exists in 40% of E. faecalis isolates. Compared with the PE-T4SS, CE-T4SS displays distinct characteristics in protein architecture and is capable of mediating large and genome-wide gene transfer in an imprecise manner. Reciprocal exchange of CE-T4SS- or PE-T4SS-associated origin of transfer (oriT) could disrupt HGT function, indicating that CE-T4SS is an independent system compared with PE-T4SS. Taken together, the CE-T4SS sheds light on the knowledge of HGT in gram-positive bacteria and triggers us to explore more evolutionary mechanisms in E. faecalis. [Display omitted] •The chromosome-encoded T4SS (CE-T4SS) mediates large and genome-wide gene transfer•The CE-T4SS mediates gene transfer in an imprecise manner•The CE-T4SS is homologous to P-type T4SS but displayed F-type T4SS mediated transferred process•The CE-T4SS exists in over 40% of E. faecalis strains Hua et al. report a chromosome-encoded type IV secretion system (CE-T4SS) in Enterococcus faecalis. The widely distributed CE-T4SS mediates large and genome-wide gene transfer in an imprecise manner. As a gene transmission device, CE-T4SS is important for the bacteria evolution and the diffusion of multi-drug-resistant Enterococcus faecalis.