Characterization of an accessory plasmid of Sinorhizobium meliloti and its two replication-modules

• DOI: 10.1371/journal.pone.0285505
• Publication Date: 2023-05-18T17:53:20Z
• Authors: Abril Luchetti; Lucas G. Castellani; Andrés Martin Tos...; Antonio Lagares; María Florencia D...; Gonzalo Torres Te...; Mariano Pistorio
• Keywords: Replicon; Sinorhizobium meliloti; Sinorhizobium; Rolling circle replication

Rhizobia are Gram-negative bacteria known for their ability to fix atmospheric N2 in symbiosis with leguminous plants. Current evidence shows that rhizobia carry most cases a variable number of plasmids, containing genes necessary or free-living, common feature being the presence several plasmid replicons within same strain. For many years, we have been studying mobilization properties pSmeLPU88b from strain Sinorhizobium meliloti LPU88, an isolate Argentina. To advance characterization plasmid, full sequence was obtained. is 35.9 kb size, had average GC % 58.6 and 31 CDS. Two replication modules were identified silico: one belonging repABC type, other repC. The presented high DNA identity pMBA9a present S. Canada. In addition, three CDS presenting recombinases toxin-antitoxin systems found downstream system. It noteworthy these genetic structure rhizobial plasmids. Moreover, all they operon. By cloning each system suicide demonstrated them can support background, but different stability behavior. Interestingly, while incompatibility analysis cloned rep results loss parental module, both obtained plasmids coexist together.