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bioRxiv · 10.1101/198473

A helicase-containing module defines a family of pCD630-like plasmids in Clostridium difficile

Smits, W. K.·Weese, J. S.·Roberts, A. P.·Harmanus, C.·Hornung, B.
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Abstract

Clostridium difficile is a Gram-positive and sporulating enteropathogen that is a major cause of healthcare-associated infections. Even though a large number of genomes of this species have been sequenced, only a few plasmids have been described in the literature. Here, we use a combination of in silico analyses and laboratory experiments to show that plasmids are common in C. difficile. We focus on a group of plasmids that share similarity with the plasmid pCD630, from the reference strain 630. The family of pCD630-like plasmids is defined by the presence of a conserved putative helicase that is likely part of the plasmid replicon. This replicon is compatible with at least some other C. difficile replicons, as strains can carry pCD630-like plasmids in addition to other plasmids. We find two distinct sub-groups of pCD630-like plasmids that differ in size and accessory modules. This study is the first to describe a family of plasmids in C. difficile.

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Smits, W. K., Weese, J. S., Roberts, A. P., Harmanus, C., Hornung, B.. 2017-10-11. A helicase-containing module defines a family of pCD630-like plasmids in Clostridium difficile. https://doi.org/10.1101/198473

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