Bias in bacterial diversity as a result of Nycodenz extraction from bulk soil

► The biodiversity of Nycodenz extracted cells is significantly lower than in the soil. ► The cell extraction underrepresents Gram-positive bacteria found in the soil. ► An overrepresentation of bacterial phyla dominated by motile species. ► One full 454 sequencing run of 16S rRNA should find 95% of OTUs in soil.