Engineering Pseudomonas fluorescens for Biodegradation of 2,4-Dinitrotoluene

MARIELA R. MONTI; ANDREA M. SMANIA; GEORGINA FABRO; MARIA E. ALVAREZ; CARLOS E. ARGARAÑA

AMER SOC MICROBIOLOGY

Lugar: Washington; Año: 2005 vol. 71 p. 8864 - 8864

b> Using the genes encoding the 2,4-dinitrotoluene degradation pathway enzymes, the nonpathogenic psychrotolerant rhizobacterium Pseudomonas fluorescens ATCC 17400 was genetically modified for degradation of this priority pollutant. First, a recombinant strain designated MP was constructed by conjugative transfer from Burkholderia sp. strain DNT of the pJS1 megaplasmid, which contains the dnt genes for 2,4-dinitrotoluene degradation. This strain was able to grow on 2,4-dinitrotoluene as the sole source of carbon, nitrogen, and energy at levels equivalent to those of Burkholderia sp. strain DNT. Nevertheless, loss of the 2,4-dinitrotoluene degradative phenotype was observed for strains carrying pJS1. The introduction of dnt genes into the P.fluorescens ATCC 17400 chromosome, using a suicide chromosomal integration Tn5-based delivery plasmid system, generated a degrading strain that was stable for a long time, which was designated R