2017  0,977
2016  0,799
2015  0,662
2014  0,740
2013  0,739
2012  0,637
2011  0,658
2010  0,654
2009  0,570
2008  0,849
2007  0,805
2006  0,330
2005  0,435
2004  0,623
2003  0,567
2002  0,641
2001  0,490
2000  0,477
1999  0,762
1998  0,785
1997  0,507
1996  0,518
1995  0,502
Vol 53(2019) N 4 p. 535-546; DOI 10.1134/S0026893319040162 Full Text

T.R. Iasakov1*, L.G. Anisimova1, N.V. Zharikova1, E.I. Zhurenko1, V.V. Korobov1, T.V. Markusheva1

Evolution and Comparative Genomics of the pSM22 Plasmid of the IncF/MOBF12 Group

1Ufa Institute of Biology, Ufa Federal Research Center, Russian Academy of Sciences, Ufa, 450054 Russia

Received - 2018-08-24; Revised - 2019-01-24; Accepted - 2019-01-28

A new plasmid, pSM22, was isolated from Serratia marcescens and sequenced. Its 43 190-bp sequence with an average GC-content of 58% contains 31 open reading frames (ORFs) which form replication, conjugation, stability, and adaptive modules. The replication module includes a site of initiation of leading-strand synthesis in plasmid replication, a replication termination site (terC), the rep A (=repA1) and repA4 genes, and the copA sequence, which codes for an antisense RNA (asRNA). These structures are functionally integrated in an FII replicon (incompatibility group IncFII). Based on the significant differences between the FII replicon and the canonical sequences of the R plasmids R1 and NR1 (=R100=R222), pSM22 was assigned to a new subtype. The conjugation module includes 13 genes with a high identity to the genes responsible for conjugation of the F plasmid. A comparative genomic analysis showed that the conjugation modules of pSM22 and F are structurally similar. By the conjugation system and the presence of three conserved motifs in relaxase (TraI), pSM22 belongs to the F12 clade of the MOBF type. The stability module includes the resD and parA genes, which are responsible for the resolution of multimeric plasmid forms and their subsequent segregation between daughter cells. The adaptive module contains the microcin H47 (MccH47) secretion/processing and UV resistance genes. The mosaic structure of pSM22 and reductive evolution of its modules suggest high genomic plasticity for the genus Serratia. An analysis of the architecture of the pSM22 modules clarifies the evolutionary relationships among IncF/MOBF12 group plasmids in bacteria of the family Enterobacteriaceae and opens a novel avenue for further comparative genomic studies of Serratia plasmids.

plasmid, pSM22, IncF/MOBF12, ori, repA, evolution, comparative genomics, Serratia marcescens, replicon, relaxase