Detection of monochlorobenzene metabolizing bacteria under anoxic conditions by DNA-stable isotope probing

• Published in: Biodegradation (Dordrecht) 2011-09, Vol.22 (5), p.973-982
• Main Authors: Martínez-Lavanchy, Paula M., Dohrmann, Anja Bettina, Imfeld, Gwenaël, Trescher, Karin, Tebbe, Christoph C., Richnow, Hans-Hermann, Nijenhuis, Ivonne
• Format: Article
• Language: English
• Subjects: Anaerobic conditions; Anaerobiosis; Analysis; Anoxic conditions; Aquatic Pollution; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - metabolism; Biodegradation; Biodegradation of pollutants; Biodegradation, Environmental; Biodiversity; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Carbon dioxide; Carbon Isotopes - chemistry; Carbon sources; Chlorobenzene; Chlorobenzenes - metabolism; Deoxyribonucleic acid; DNA; DNA sequencing; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Environment and pollution; Fresh Water - microbiology; Fundamental and applied biological sciences. Psychology; Genetic polymorphisms; Geochemistry; Groundwater pollution; Industrial applications and implications. Economical aspects; Isotope Labeling; Life Sciences; Metabolism; Metabolites; Methane; Methane - metabolism; Microbiology; Microcosms; Molecular Sequence Data; Nucleotide sequencing; Organic contaminants; Original Paper; Oxygen - metabolism; Phylogenetics; Phylogeny; Proteobacteria; RNA; RNA, Ribosomal, 16S - chemistry; RNA, Ribosomal, 16S - genetics; Soil Science & Conservation; Stable isotopes; Terrestrial Pollution; Waste Management/Waste Technology; Waste Water Technology; Water Management; Water Pollution Control; Water, Underground
• ISSN: 0923-9820; 1572-9729
• DOI: 10.1007/s10532-011-9456-2

Cultivation-independent analyses were applied to study the structural diversity of the bacterial community which developed in groundwater inoculated microcosms actively metabolizing monochlorobenzene (MCB) under anaerobic conditions. Addition of 13 C-labelled MCB demonstrated that the community produced 13 CO 2 as a metabolite at slightly increasing rates over a period of 1,051 days while no 13 C-methane evolved. Genetic profiles of partial 16S rRNA genes generated with the single-strand conformation polymorphism (SSCP) technique by PCR from directly extracted total DNA revealed that, despite the long incubation period, six replicate microcosms were characterized by almost the same microbial members. Nine distinguishable contributors to the SSCP-profiles were characterized by DNA sequencing, revealing the presence of different members from the phyla Proteobacteria , Fibrobacteres and from the candidate division OD1. DNA-stable isotope probing (SIP) was applied to distinguish the actual MCB metabolizing bacteria from the other community members. This study reveals for the first time the structural diversity of an anaerobic MCB metabolizing bacterial community. However, it also demonstrates the limitations of SIP to detect bacteria slowly metabolizing carbon sources under anaerobic conditions.