Genetic Analysis of the Mobilization and Leading Regions of the IncN plasmids pKM101 and pCU1

Abstract

The conjugative IncN plasmids pKM101 and pCU1 have previously been shown to contain identical oriT sequences as well as conserved restriction endonuclease cleavage patterns within theirtra regions. Complementation analysis and sequence data presented here indicate that these two plasmids encode essentially identical conjugal DNA-processing proteins. This region contains three genes, traI, traJ, and traK, transcribed in the same orientation from a promoter that probably lies within or near the conjugal transfer origin (oriT). Three corresponding proteins were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and complementation analysis confirmed that this region contains three tracomplementation groups. All three proteins resemble proteins of the IncW plasmid R388 and other plasmids thought to have roles in processing of plasmid DNA during conjugation. The hydropathy profile of TraJ suggests a transmembrane topology similar to that of several homologous proteins. Both traK and traI were required for efficient interplasmid site-specific recombination atoriT, while traJ was not required. The leading region of pKM101 contains three genes (stbA,stbB, and stbC), null mutations in which cause elevated levels of plasmid instability. Plasmid instability was observed only in hosts that are proficient in interplasmid recombination, suggesting that this recombination can potentially lead to plasmid loss and that Stb proteins somehow overcome this, possibly via site-specific multimer resolution.

Use of chimeric type IV secretion systems to define contributions of outer membrane subassemblies for contact‐dependent translocation

“…S1). A donor carrying mini-pKM101 pRP100 mobilized transfer of pJG142, a plasmid that carries the entire traK/traJ/ traI/oriT mobilization (mob) region from pKM101 (Paterson et al, 1999), at frequencies slightly higher than observed for pKM101 in both solid surface and liquid matings (Fig. 1).…”

“…coli pKM101 is widely known for its mutagenic and protective properties in cells exposed to UV irradiation and other DNA-damaging agents (Ames et al, 1975). pKM101 also encodes a highly-efficient T4SS (Winans and Walker, 1985;Paterson et al, 1999). In this study, we capitalized on the construction of a pKM101 aeruginosa PAO1.…”

Genomic Diversity, Virulence, and Antimicrobial Resistance ofKlebsiella pneumoniaeStrains from Cows and Humans

“…We then compared the genetic background of pC5 with that of seven publicly available plasmid sequences with high similarity (coverage, Ͼ90%; identity, Ͼ99%), all of which were identified in E. coli strains in European countries (20,21,22,23) (Table 1). They all maintained a typical IncN plasmid backbone scaffold, including a replicon and genes involved in plasmid stability, mutagenesis enhancement, antirestriction functions, and conjugative transfer (24). The difference among these plasmids was in the mosaic region that carried resistance genes and in the mobile genetic elements represented (Fig.…”

Identification of bacterial plasmids based on mobility and plasmid population biology

“…A classical example is the primase gene sog of REP I1 -MOB P12 plasmids, which is only partially required for conjugation between Escherichia coli cells (Chatfield et al, 1982), but is required to expand the recipient host range to Salmonella and other enterobacteria (Lanka & Barth, 1981). Mutations in genes stbABC located in the leading region of REP N -MOB F11 plasmid pKM101 decreased plasmid stability (Paterson et al, 1999). Homologs of gene ardA are present in the leading region of REP N -MOB F11 , REP Frep -MOB F12 and (Gotz et al, 1996); N (Carattoli et al, 2005) oxa2, aadA1, sul1, tetAR, asrABCDR S. Typhimurium (E, P, V, A) pWWO 116 580…”