Conjugal transfer of plasmid pNB2 to activated sludge bacteria leads to 3‐chloroaniline degradation in enrichment cultures

• Published in: Letters in applied microbiology Vol. 38; no. 6; pp. 527 - 531
• Main Author: Bathe, S.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.06.2004; Blackwell Science
• Subjects: Aniline Compounds - metabolism; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - metabolism; bioaugmentation; Biodegradation, Environmental; Biological and medical sciences; catabolic plasmid; Chromosomes, Bacterial - genetics; Chromosomes, Bacterial - physiology; Comamonas testosteroni; Comamonas testosteroni - classification; Comamonas testosteroni - isolation & purification; Comamonas testosteroni - metabolism; conjugation; Conjugation, Genetic; DNA, Bacterial - chemistry; DNA, Bacterial - isolation & purification; DNA, Ribosomal - chemistry; DNA, Ribosomal - isolation & purification; Fundamental and applied biological sciences. Psychology; Genes, Bacterial; Genes, rRNA - genetics; horizontal gene transfer; Microbiology; Molecular Sequence Data; Phylogeny; Plasmids; Pseudomonas putida; Pseudomonas putida - genetics; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Sewage - microbiology; transconjugant; Degradation; Enrichment; Plasmid; Activated sludge; transconjugant; Applied microbiology; Bacteria; Conjugation; catabolic plasmid; Bioaugmentation; horizontal gene transfer; Genetic transfer
• ISSN: 0266-8254; 1472-765X; 1365-2673
• DOI: 10.1111/j.1472-765X.2004.01532.x

Aims:  The involvement of the aniline‐degradative plasmid pNB2 in degradation of 3‐chloroaniline (3‐CA) was investigated. Methods and Results:  Plate matings of a Pseudomonas putida strain containing pNB2 with a mixed bacterial culture derived from activated sludge was carried out. After inoculation of the mating mixtures into batch cultures containing 3‐CA, degradation of the compound was observed. A total of five different transconjugant strains could be isolated from one of the batch cultures and two of them were able to degrade 3‐CA. These two isolates were identified as Comamonas testosteroni by partial 16S rDNA sequencing. Conclusions:  It can be assumed that pNB2 carries a part of the genes involved in the catabolism of 3‐CA, but that completion of the pathway must be provided by chromosomal genes in the host strain. Significance and Impact of the Study:  pNB2 is a candidate plasmid which can be used in plasmid‐mediated bioaugmentation of wastewater bacteria involved in degradation of chlorinated anilines.