Spatial distribution of 16S rRNA levels from uncultured acidobacteria in soil.

The activity of uncultured acidobacteria was monitored in Dutch grassland soils by quantifying their ribosomes. These bacteria were detectable by five different 16S rRNA RT-PCR products in temperature gradient gel electrophoresis fingerprints. The ribosomes in surface soil samples were quantified with multiple competitive RT-PCR along a 1.5-km transect through the grassland. In total, the five members of the acidobacteria were estimated to contribute 4 x 1010 to 1 x 1011 ribosomes g soil-1, representing 7-14% of all bacterial ribosomes. These results indicate that ribosomes from acidobacteria are continuously present and abundant in soil and might contribute significantly to microbial activity in soil.