Sequence analysis of five endogenous plasmids isolated from Lactobacillus pentosus F03

Lactobacillus pentosus F03, a strain isolated from pig intestines in Taiwan, contains multiple endogenous plasmids. We isolated, completely sequenced, and characterized five of the plasmids present in L. pentosus F03 designated as pF03-1 (3282bp), pF03-2 (3293bp), pF03-3 (1787bp), pF03-4 (2138bp), and pF03-5 (1949bp). The replication types of these plasmids were predicted by comparing the features of the replicon nucleotides and the similarity of replication proteins with those of the plasmids of known replication types. The results of basic local alignment search tool analyses indicate that these plasmids, except for pF03-4, belong to different replicating plasmid families. According to replicon and initiator protein analyses, pF03-1, pF03-2, and pF03-3, were determined to belong respectively to the pMV158, pC194/pUB110, and pT181 families of rolling-circle replication plasmids. However, pF03-5 contains the typical features observed in the family of theta-replicating plasmids and belongs to the pUCL287 family of theta-replicating plasmids.