Cupriavidus pampae sp. nov.,a novel 4-(2,4-dichlorophenoxy) butyric acid herbicide-degrading bacterium isolated from agricultural soil of the Argentinean Humid Pampa region

CUADRADO, V; GOMILA, M; MERINI, LJ; GIULIETTI, AM; MOORE, E

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY.

SOC GENERAL MICROBIOLOGY

Año: 2010 p. 2606 - 2612

1466-5026

A bacterial consortium able to degrade the herbicide 4-(2,4-di 32 chlorophenoxy) butyric acid (2,4-DB) was obtained from an agricultural soil of the Argentinean Humid Pampa region with a longterm history of herbicide use. Four bacterial strains were isolated from the consortium and identified as members of the genera Cupriavidus, Labrys and Pseudomonas. A polyphasic systematic analysis was carried out on strain CPDB6T, the member of the 2,4-DB degrading consortium able to degrade 2,4-DB as a sole carbon and energy source. The Gram-negative, rodshaped, motile, non-sporulating, non-fermenting bacterium was recognised to belong to the genus Cupriavidus, on the basis of 16S rRNA gene sequence analyses. Strain CPDB6T did not reduce nitrate, which differentiated it from the genus type species, C. necator; it did not grow at 0.5-4.5% NaCl, although most species of Cupriavidus are able to grow at NaCl concentrations as high as 1.5%; and it was able to deamidate acetamide, which differentiated it from all other species of Cupriavidus. DNA-DNA hybridisations determined low levels of genomic DNA similarities (less than 30%) between strain CPDB6T and the type strains of the validly published species of Cupriavidus. The major cell fatty acids detected were cis-9-hexadecenoic (16:1 7c) and hexadecanoic (16:0) acids. On the basis of phenotypic and genotypic characterisations, strain CPDB6T was recognised to represent a novel species within the genus Cupriavidus. The name Cupriavidus pampae sp. nov. is proposed, with strain CPDB6T (= CCUG 55948T = CCM-A-29:1289T) as the type strain of the species.