Direct Extraction and Molecular Analysis of DNA from Soil and Geothermal Sediment
Dianna E. WILKINSON*, Thomas JAENICKE, and Don A. COWAN
Department of Biochemistry and Molecular Biology, University College London, Gower Street, London WC1E6BT, UK
Molecular phylogenetic analyses using nucleic acids extracted directly from environmental samples have revealed genetically diverse microbial populations (e.g. 1,2,3). Since it is generally believed that less than 1% of naturally occurring micro- organisms are able to be cultivated, such genetic diversity implies a largely untapped resource of novel and potentially biotechnologically important biomolecules.
The same culture-independent nucleic acid-based techniques which have been used to characterise 16S rRNA gene sequences are increasingly being used to isolate and characterise DNA sequences of metabolic and biochemical importance (e.g. 3,4). For the purpose of detecting and characterising gene target sequences, we have developed a protocol for lysing indigenous micro-organisms and extracting DNA directly from soil and sediment. Two pUC19 total community libraries have been prepared from a soil (Gordon Square, London) and from a geothermal sediment material (Tokaanu thermal region, central North Island, New Zealand). Evaluation of the direct lysis and DNA extraction and purification procedures as well as molecular analysis of the environmental DNA will be presented.
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