Characterization of a phage-like pyocin from the plant growth-promoting rhizobacterium Pseudomonas fluorescens SF4c

SONIA FISCHER; AGUSTINA GODINO; JOSÉ MIGUEL QUESADA; PAULA CORDERO; EDGARDO JOFRÉ ; GLADYS MORI; MANUEL ESPINOSA-URGEL

SOC GENERAL MICROBIOLOGY

Lugar: London; Año: 2012 p. 1493 - 1493

-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria. A mutant deficient in production of this antimicrobial compound was obtained by transposon mutagenesis. Sequence analysis revealed that the transposon had disrupted a gene that we have named ptm, since it is homologous to that encoding phage tape-measure protein in P. fluorescens Pf0-1, a gene belonging to a prophage similar to phage-like pyocin from P. aeruginosa PAO1. In addition, we have identified genes from the SF4c pyocin cluster that encode a lytic system and regulatory genes. We constructed a nonpolar ptm mutant of P. fluorescens SF4c. Heterologous complementatio