Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2003
Publication Date: June 1, 2003
Citation: Press,C. M. Brodhagen, M., and Loper, J.E.Gene expression profiles of the biocontrol agent Pseudomonas fluorescens Pf-5 assessed using oligonucleotide arrays. Phytopathology 93:S72. Technical Abstract: P.fluorescens Pf-5 is a root-colonizing biocontrol agent that produces a variety of antibiotics including pyoluteorin (Plt). Plt biosynthesis requires PltR, a transcriptional activator of Plt biosynthesis genes. A small-scale array, composed of 81 oligonucleotides representing structural and regulatory genes involved in biological control, was developed to evaluate patterns of gene expression in Pf-5. Arrays were targeted with cDNA transcribed from RNA extracted from cultures of Pf-5 or a pltR mutant. Transcripts of Plt biosynthesis genes were more abundant in Pf-5 than in the pltR mutant, as expected. Five other genes on the array (infC,rsmA,colR,hupB and mexB)were differentially expressed by Pf-5 and the pltR mutant, and significant differences in transcript levels were confirmed with quantitative PCR. The influence of PltR on transcription of diverse structural and regulatory genes in Pf-5 was demonstrated through anaylsis of oligonucleotide arrays.