Abstract
With the abuse of macrolide, lincosamide, and streptogramin (MLS), the traditionally safe bifidobacterial strains in the human intestine could serve as a reservoir of MLS resistance genes. In this study, the erm(X) gene was detected in 29 MLS-resistant strains and one MLS-susceptible strain among 92 bifidobacterial strains of human origin. This study is the first to report erm(X)-mediated MLS resistance in Bifidobacterium pseudocatenulatum, Bifidobacterium breve and Bifidobacterium bifidum. The insertion sequences (ISs) flanking antibiotic resistance (AR) genes (i.e., the genetic environment of AR genes) could contribute to the horizontal spreading of AR. However, the potential transferability of erm(X) in bifidobacteria has not been previously verified. Here, we retrieved four genetic environments (I–IV) of erm(X) from 30 erm(X)-positive bifidobacterial strains. This study is the first to identify the erm(X) gene in three new genetic environments (II, III and IV) in bifidobacteria. The erm(X) gene was individually flanked by IS1249 or IS3 in genetic environments I, II and IV and was simultaneously flanked by IS1249 and IS3 elements in genetic environment III. Only the transfer of erm(X) from genetic environment III simultaneously flanked by IS1249 and IS3 elements was successfully observed in filter mating experiments. These findings indicate a synergic effect of IS1249 and IS3 elements in the transfer of erm(X) in bifidobacteria, and further reveal that the various genetic environments of erm(X) result in significant differences in the transferability of erm(X) in bifidobacteria.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.