Figure 1 Organization of prophage 01 from P. fluorescens Pf-5 [49], related prophages in the mutS-recA region of the genomes of other P. fluorescens strains, and bacteriophages CTX [81]and SfV [16]. Predicted open reading frames and their orientation are shown by arrows shaded according to their functional category. Homologous ORFs are connected with lines. We (D.V.M. and L.S.T.) previously identified a highly similar prophage element during a study focused on genetic traits contributing to colonization of the plant rhizosphere by P. fluorescens. In that project [17], we applied genomic subtractive hybridization to two strains of P. fluorescens, Q8r1-96 and Q2-87, which differ

in their ability to colonize wheat roots. Among 32 recovered Q8r1-96-specific loci was a clone dubbed ssh6, which proved to constitute part of a 22-kb prophage element that closely buy S63845 resembles prophage 01 of strain Pf-5 (Figs. 1 and 2; see Additional file 2). Like its counterpart, the ssh6 prophage from Q8r1-96 carries genes for a myovirus-like tail (orf10 through orf21), the lytic enzymes holin (hol) and endolysin (lys), and a Cro/CI-like repressor protein (prtR) (Fig. 1; see Additional file 2). Genes in the Q8r1-96 cluster that are not present in Pf-5 encode a colicin M-like bacteriocin (cma), a tail collar protein (orf23), and putative tail fiber proteins (orf22 and orf25). Interestingly, the

colicin M-like ORF from the ssh6 prophage of Q8r1-96 also encodes an enzymatically active protein although the range of microorganisms sensitive to this bacteriocin is currently unknown (Dr. Dominique Mengin-Lecreulx, Selleck LY2606368 Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Tacrolimus (FK506) Université Paris-Sud, Orsay, France; personal communication). Figure 2 Dot plot comparison of P. fluorescens Pf-5 prophages with similar prophage regions in the genomes of P. fluorescens Q8r1-96 [GenBank EU982300], P. fluorescens Pf0-1 [GenBank CP000094], P. ZD1839 syringae pv. tomato DC3000 [24], P. syringae pv. syringae B728a [36], P. syringae pv. phaseolicola 1448a [37], P. putida KT2440 [25], P. aeruginosa PA01 [82], P. aeruginosa

UCBPP-PA14 [35], and P. aeruginosa PA7 [GenBank CP000744]. All prophage sequences were extracted from genomes, concatenated and aligned using a dot plot function from OMIGA 2.0 with a sliding window of 45 and a hash value of 6. Genome regions used in the analysis encompass open reading frames with following locus tags: P. fluorescens Pf0-1 prophage1 – Pfl01_1135 through Pfl01_1173; P. syringae pv. tomato DC3000 prophage1 – PSPTO_0569 through PSPTO_0587; P. syringae pv. tomato DC3000 prophage3 – PSPTO_3385 through PSPTO_3432; P. syringae pv. syringae 728a genomic island GI11 – Psyr_2763 through Psyr_2846; P. syringae pv. syringae 728a genomic island GI12 – Psyr_4582 through Psyr_4608; P. syringae pv. phaseolicola 1448a prophage1 – PSPPH_0650 through PSPPH_0671; P. putida KT2440 P2 like pyocin – PP3031 through PP3066; P.