Genetic and Functional Properties of the Self-Transmissible Yersinia enterocolitica Plasmid pYE854, Which Mobilizes the Virulence Plasmid pYV

Abstract

Yersinia strains frequently harbor plasmids, of which the virulence plasmid pYV, indigenous in pathogenic strains, has been thoroughly characterized during the last decades. Yet, it has been unknown whether the nonconjugative pYV can be transferred by helper plasmids naturally occurring in this genus. We have isolated the conjugative plasmids pYE854 (95.5 kb) and pYE966 (70 kb) from a nonpathogenic and a pathogenic Yersinia enterocolitica strain, respectively, and demonstrate that both plasmids are able to mobilize pYV. The complete sequence of pYE854 has been determined. The transfer proteins and oriT of the plasmid reveal similarities to the F factor. However, the pYE854 replicon does not belong to the IncF group and is more closely related to a plasmid of gram-positive bacteria. Plasmid pYE966 is very similar to pYE854 but lacks two DNA regions of the larger plasmid that are dispensable for conjugation.

Evolutionary Dynamics of the Yersinia enterocolitica Complex

“…Interestingly, pYE854 was isolated from a non-pathogenic BT 1A strain, which is known never to carry the virulence plasmid (Cornelis, et al, 1987;Lepka, et al, 2009;Wren 2003). The study suggests though that self-transmissible plasmids are common amongst Yersiniae as they also found a plasmid related to pYE854 which could also mobilize pYV (Hammerl, et al, 2008). pYE854 potentially belongs to an unknown incompatibility group as it showed no homology with the known incompatibility groups (Hammerl, et al, 2008).…”

“…The study suggests though that self-transmissible plasmids are common amongst Yersiniae as they also found a plasmid related to pYE854 which could also mobilize pYV (Hammerl, et al, 2008). pYE854 potentially belongs to an unknown incompatibility group as it showed no homology with the known incompatibility groups (Hammerl, et al, 2008). Furthermore co-carriage of pYE854 with plasmids of various incompatibility groups was shown (Hammerl, et al, 2008).…”

“…pYE854 potentially belongs to an unknown incompatibility group as it showed no homology with the known incompatibility groups (Hammerl, et al, 2008). Furthermore co-carriage of pYE854 with plasmids of various incompatibility groups was shown (Hammerl, et al, 2008). As pSR4-5 shares the replication protein with pYE854, they might belong to the same incompatibility group.…”

“…pSR4-5 was also found to be present in two other BT 5 isolates sequenced in a larger strain collection. A similar plasmid, pYE854, has been isolated from a non- pathogenic BT 1A strain (Hertwig, Klein, Hammerl and Appel, 2003;Hammerl, et al, 2008). A comparison between these two plasmids is shown in Figure 5.13.…”

“…Both plasmids have about 60 kb in common, including the conjugative transfer region, as well as replication and plasmid partitioning region. Additionally, pYE854 carries a phosphotransferase system potentially involved with the transport and metabolism of sugars, although functionality could not be shown (Hammerl, et al, 2008). pYV854 was shown to be able to transfer not only itself but also mobilize the virulence plasmid pYV in experimental studies (Hammerl, et al, 2008).…”