c Pseudomonas putida strain ND6 is an efficient naphthalene-degrading bacterium. The complete genome of strain ND6 was sequenced and annotated. The genes encoding the enzymes involved in catechol degradation by the ortho-cleavage pathway were found in the chromosomal sequence, which indicated that strain ND6 is able to metabolize naphthalene by the catechol metaand ortho-cleavage pathways. Pseudomonas putida strain ND6 is capable of utilizing naphthalene as a sole carbon and energy source for growth. As reported previously, the naphthalene-degrading genes of P. putida ND6 were located on a plasmid of 101,858 bp, pND6-1 (6), encoding the enzymes for the conversion of naphthalene to tricarboxylic acid cycle intermediates through the catechol meta-cleavage pathway. Most of the naphthalene catabolic genes of pND6-1 have 99 to 100% identity to the amino acid sequences of their counterparts found in plasmid pDTG1 (3) and NAH7 (10). Moreover, P. putida ND6 harbors a cryptic plasmid of 117,003 bp, pND6-2, which has been sequenced and annotated (GenBank accession no. CP003589). The plasmid contains 32 coding sequences (CDSs) encoding proteins associated with plasmid conjugative transfer, which can assist the naphthalene catabolic plasmid pND6-1 without any conjugative genes being transferred from P. putida ND6 to Escherichia coli AD256 (unpublished data).The genome of P. putida ND6 was sequenced with a combined strategy using Roche 454 pyrosequencing (7) and Illumina sequencing by synthesis. The low-quality sequences were trimmed before assembly. The Illumina mate-paired reads (1,356.0 Mbp; 226ϫ coverage) generated by Solexa sequencer were assembled by SOAPdenovo (5). Then, the 454 reads (114.9 Mbp; 18.9ϫ coverage) and the split fragments of contigs generated by SOAPdenovo were used for a hybrid assembly with the Newbler sequence assembler (version 2.6). To finish the genome, conventional Sanger sequencing technologies were used to fill the gaps. Coding sequences were predicted by Glimmer3 (2). Functional assignment and classification were obtained by performing sequence similarity search with BLAST (E-value cutoff, 1EϪ5) (1) against the egg-NOG database (8), the KEGG reference database (4), and the nonredundant GenBank CDS database.

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Atrazine is an s-triazine herbicide that has been used widely over 50 years. This has resulted in the contamination of surface water, groundwater and soil. For the bioremediation of atrazine-contaminated environments, we investigated the biodegradation of atrazine and bioremediation of atrazine-contaminated soil by two groups of mixed bacteria (Pseudomonas sp. ADP and Arthrobacter aurescens TC1; Arthrobacter sp. AD30 and Pseudomonas sp. AD39) and a bacterial consortium. The biodegradation experiments indicated that after the minimal medium containing 300 mg/L atrazine as nitrogen source and 3000 mg/L sucrose as carbon source were inoculated with the above-mentioned two groups of mixed bacteria and bacterial consortium and incubated at 30 with shaking for 48 h, atrazine were removed by 80% (ADP+TC1), 97% (AD30+AD39), and 96% (bacterial consortium), respectively. The bacterial consortium and the mixed bacteria containing Arthrobacter sp. AD30 and Pseudomonas sp. AD39 exhibited higher atrazine biodegradation activities. A bioremediation trial of atrazine-contaminated soil by the bacterial consortium and mixed bacteria containing AD30 and AD39 have indicated that after incubating for 15 d at 30 atrazine contained in soil (100 mg/kg) were completely removed. These results indicated that the bacterial consortium and the mixed bacteria containing AD30 and AD39 are good candidates for use in bioremediation of atrazine-contaminated soil.

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