Jitka Navratilova, Ludmila Tvzova, Eva Durnova, Cathrin Spöer, Ivo Sedlacek, Jiri Neca and Miroslav Nemec, 
Characterization of Rhodococcus wratislaviensis strain J3 that degrades 4-nitrocatechol and other nitroaromatic compounds, Antonie van Leeuwenhoek 00: 1–5, 2004

ABSTRACT

The bacterial strain J3 was isolated from soil by selective enrichment on mineral medium containing 4-nitrocatechol as the sole carbon and energy source. This strain was identified as Rhodococcus wratislaviensis on the basis of morphology, biochemical, physiological and chemotaxonomic characterization and complete sequencing of the 16S rDNA gene. The isolated bacterium could utilize 4-nitrocatechol, 3-nitrophenol and 5-nitroguaiacol as sole carbon and energy sources. Stoichiometric release of nitrites was measured during degradation of 4-nitrocatechol both in growing cultures and for stationary phase cells. The J3 strain was unable to degrade 4-nitroguaiacol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrobenzoic acid, 4,5-dimethoxy-2-nitrobenzoic acid and 2,3-difluoro-6-nitrophenol. The J3 strain is deposited in the Czech Collection of Microorganisms as CCM 4930.

INTRODUCTION

Nitroaromatic compounds are common pollutants produced in developed countries by the industrial manufacture of dyes, explosives, pesticides, herbicides and drugs (Spain and Gibson 1991). They are abundant in the environment and are found, in particular, as contaminants in wastewater, rivers, and soils treated with herbicides or pesticides (Yoon et al. 2000). The presence of the nitro group makes such compounds more resistant to biodegradation than the unsubstituted analogs. Nitroaromatics and the transformation products of their degradation have relatively high acute toxicity and some may be potential carcinogens (Spain 1995). The members of the order Actinomycetales are important bacteria that have potential for bioremediation. Some of them, e.g. the rhodococci, are widely distributed in soil and sludge and have been shown to attack various xenobiotic compounds (Spain and Gibson 1991).