Microbiology and 16S rDNA molecular ecology of a polluting neutral mine drainage sediment

摘要

This paper deals with genetic techniques for determining microorganisms active in ochreous minewaters and contributes to the development of techniques for the rapid identification and enumeration of microorganisms present in post-industrial environmental effluents. Enrichment media for iron bacteria and environmentally-derived bacterial 16S rDNA clone libraries were used to study the microbiology of a sediment from a polluting near-neutral pH minewater sediment located near Stocksbridge, Yorkshire, UK. Enrichment was successful for the bacterium Gallionella ferruginea, which has been implicated in environmental iron redox processes. One clone out of 25 yielded sequences similar to known iron bacteria, in particular a 98.1% match for G. ferruginea. Construction of phylogenetic trees showed that 54% of the clones grouped within three separate clusters which were related to methane utilising, ammonia oxidising and non-purple photosynthetic bacteria. Analyses of sediment and water samples led to a rationalisation of minewater species potentially identifiable by 16S rDNA studies. As with soils, it appears that most of the microbial species in minewaters remain unidentified.