General (Biolog GN) versus site-relevant (pollutant-dependent) sole-carbon-source utilization patterns as a means to approaching community functioning

Biolog community-level sole-carbon-source utilization patterns are widely applied to distinguish between the microbiota of different habitats or reveal disturbances in microbial ecosystems. Our objective was to examine whether the metabolic diversity measured in the Biolog system could be related to community functioning, thus providing more information than being merely discriminative for communities. To answer this question, we compared the percentages of specific pollutant utilizers with the percentages of the degraders of distinct general (Biolog) substrates in arbitrary samples of isolates, employing in both cases the isolate sample assay (ISA). Samples for arbitrarily selected isolates were taken from in situ enclosures situated in the anaerobic lignite-carbonization effluent Lake Schwelvollert (district of Wiessenfels, Saxony-Anhalt, Germany). A different aerobic-carbonization wastewater treatment was carried out in each of the in situ enclosures. It was shown that distinct arbitrarily compiled isolate samples, which displayed similar functional patterns in terms of the degradation of pollutant-related compounds, exhibited significantly different general metabolic capacities as measured using Biolog kits. The similar pollutant-degradation potentials of the arbitrary isolates indicated that the site's substrate supply plays an important role in deciding which bacteria can become indigenous, seemingly leaving room for the otherwise varying properties of the individual community members.