Skin 1 had relatively more Bacteroidales and Clostridiales (c. 20–30%), while Skin 2 had greater abundances of the Actinobacteridae and Bacillales (c. 35–55%) (Fig. 2). These person-to-person differences in taxon abundance were also evident in the UniFrac analyses, as each sample clustered by host rather by temperature or length of storage (Fig. 1). Weighted

selleck screening library pairwise UniFrac distances were significantly greater between the samples from the two individuals (P<0.001) than between replicate subsamples stored at different temperatures (P=0.93) or durations (P=0.53). Similarly, we observed no significant effect on the phylogenetic diversity between replicate subsamples analyzed after 3 days of storage vs. 14 days of storage, irrespective of the storage temperature (P>0.05 in all cases). The fact that the highly personalized nature of skin-associated bacterial communities AP24534 (Gao et al., 2007; Costello et al., 2009; Grice et al., 2009) was still apparent after 14 days at a range of temperatures, with storage conditions having relatively little impact on the community composition or diversity, has important implications for mass sampling efforts sponsored

by various international human microbiome projects, which aim to relate microbial community structure and function to physiologic and pathophysiologic features in individuals with a range of lifestyles in a variety geographic locations, some remote (Turnbaugh et al., 2007). The two soils harbored unique bacterial communities, with temperature and length of storage having little effect on the overall community composition (Figs 1 and 2, Table TCL 1). Soils retained similar abundances of the six most numerous taxa across the range of storage temperatures tested, except for the Burkholderiales, which were marginally affected by temperature in Soil 1 (P=0.05, Fig. 2). Although each sample had similar abundances of most taxa, the two soil communities were clearly distinct regardless of the storage conditions (P<0.001, Fig. 1 and Table 1).

Analysis of UniFrac pairwise distances showed no significant effect of Day, Temperature or Day × Temperature on the overall community composition for subsamples immediately frozen at −80 °C and those stored at 20 °C for 14 days (P>0.05 in all cases). Likewise, phylogenetic diversity was unaffected by temperature or length of storage (P>0.05 in all cases, Table 2). We surveyed microbial communities from multiple environments under a broad range of storage conditions, and demonstrated that the bacterial community composition in the samples was largely unaffected by differences in short-term storage conditions. Although it is not currently possible to resolve changes in bacteria at the species or the strain level using pyrosequencing, given the limitations of read length and error rate (Kunin et al.