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We have developed a simple method for the quantitative detection of specific DNA or RNA molecules based on the finding that BODIPY((R)) FL fluorescence was quenched by its interaction with a uniquely positioned guanine. This approach makes use of an oligonucleotide probe or primer containing a BODIPY((R)) FL-modified cytosine at its 5'-end. When such a probe was hybridized with a target DNA, its fluorescence was quenched by the guanine in the target, complementary to the modified cytosine, and the quench rate was proportional to the amount of target DNA. This widely applicable technique will be used directly with larger samples or in conjunction with the polymerase chain reaction to quantify small DNA samples.

A trichloroethylene (TCE)-degrading bacterium was isolated from an aquifer sample collected at a TCE-polluted site in Japan by enriching with phenol as sole carbon source. The isolate, designated strain KP23 T , was a Gram-negative, oval-shaped micro-organism. A phylogenetic study based on 16S rRNA gene sequences indicated that strain KP23 T should be placed in the genus Burkholderia. Cellular fatty acids of the strain were mainly composed of C 16 :0 , cyclopropanic acid C 17 :0 and cyclopropanic acid C 19 :0 . Strain KP23 T also contained notable amounts of C 13 :1 and C 17 :1 . The GMC content of total DNA was 64 8 mol %. Strain KP23 T oxidized various sugars and sugar alcohols as sole carbon source such as galactose, glucose, mannose, maltose, glycerol, inositol and mannitol. Comparisons of its phenotypic and genotypic characteristics with other known species belonging to the genus Burkholderia suggested that strain KP23 T represents a new species in the genus. The name Burkholderia kururiensis is proposed for this species, with strain KP23 T as the type strain (l JCM 10599 T ).Keywords : trichloroethylene degradation, Burkholderia kururiensis sp. nov., aquifer, 16S rRNA gene INTRODUCTIONTrichloroethylene (TCE) has been used as a solvent in manufacturing to clean grease from machinery all over the world. Like many other chlorinated hydrocarbons, it has become one of the most abundant environmental pollutants because of its toxic properties and widespread occurrence in soil and groundwater in many countries. TCE removal by dumping or air stripping is restricted by legislation and thus attention is now being paid to biological degradation in soil and groundwater. In the past decade, research on the application of bacteria to the aerobic biodegradation of TCE has progressed and a wide variety of microorganisms has been investigated for this purpose. Most of these bacteria belong to the Proteobacteria such as Methylococcus capsulatus (Stainthorpe et al., 1990) Abbreviations : FAME, fatty acid methyl ester ; TCE, trichloroethylene ; UQ, ubiquinone.The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain KP23 T is AB024310. OB3b (Cardy et al., 1991), Methylocystis sp. strain M (McDonald et al., 1997), Pseudomonas sp. strain CF600 (Nordlund et al., 1990), Pseudomonas putida strain H (Herrmann et al., 1995), Pseudomonas putida F1 , Pseudomonas mendocina (Yen et al., 1991), Burkholderia cepacia G4 (Shields et al., 1989), Ralstonia pickettii (objective synonym of Pseudomonas pickettii) (Byrne et al., 1995) and Ralstonia eutropha (objective synonym of Alcaligenes eutrophus) (Kim et al., 1996). Methylosinus trichosporiumIn these organisms, TCE degradation is catalysed by monoxygenases or dioxygenases which are induced by specific substrates relevant to the enzymes. The inducers include various aromatic and aliphatic hydrocarbons such as toluene (Nelson et al., 1987), phenol (Folsom et al., 1990Harker & Kim, 1990), isopropylbenzene (Dabrock et al., 1992), propane and methane (Little et al., 1988 ;...

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