Silent dissemination of plasmid-borne tigecycline resistance gene tet(X6) in livestock-associated Acinetobacter towneri

Cheng, Y.; Chen, Y.; Liu, Y.; Song, J.; Guo, Y.; Zhou, Y.; Xiao, T.; Zhang, S.; Xu, H.; Chen, Y.-B.; Shan, T.; Xiao, Y.; Zhou, K.

doi:10.1101/2020.05.08.085514

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bioRxiv · 10.1101/2020.05.08.085514

Silent dissemination of plasmid-borne tigecycline resistance gene tet(X6) in livestock-associated Acinetobacter towneri

Cheng, Y.·Chen, Y.·Liu, Y.·Song, J.·Guo, Y.·Zhou, Y.·Xiao, T.·Zhang, S.·Xu, H.·Chen, Y.-B.·Shan, T.·Xiao, Y.·Zhou, K.

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Abstract

A tigecycline-resistance gene, tet(X6), was detected on a 159-kb novel plasmid carried by a tigecycline-susceptible livestock-associated Acinetobacter towneri isolate. The genetic context of tet(X6) ({Delta}ISVsa3-tet(X6)-abh-guaA-ISVsa3) is highly similar with that of the other plasmid-borne tet(X) variants. The 23-Ala residue of the first FAD binding site conferred higher activity to Tet(X6) than the 23-Gly reside conserved in the other plasmid-borne tet(X)s. To our knowledge, this is the first report of tet(X6) carried by the plasmid.

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Cheng, Y., Chen, Y., Liu, Y., Song, J., Guo, Y., Zhou, Y., Xiao, T., Zhang, S., Xu, H., Chen, Y.-B., Shan, T., Xiao, Y., Zhou, K.. 2020-05-12. Silent dissemination of plasmid-borne tigecycline resistance gene tet(X6) in livestock-associated Acinetobacter towneri. https://doi.org/10.1101/2020.05.08.085514

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