Linking microbial community structure to β-glucosidic function in soil aggregates

Abstract

To link microbial community 16S structure to a measured function in a natural soil, we have scaled both DNA and b-glucosidase assays down to a volume of soil that may approach a unique microbial community. b-Glucosidase activity was assayed in 450 individual aggregates, which were then sorted into classes of high or low activities, from which groups of 10 or 11 aggregates were identified and grouped for DNA extraction and pyrosequencing. Tandem assays of ATP were conducted for each aggregate in order to normalize these small groups of aggregates for biomass size. In spite of there being no significant differences in the richness or diversity of the microbial communities associated with high b-glucosidase activities compared with the communities associated with low b-glucosidase communities, several analyses of variance clearly show that the communities of these two groups differ. The separation of these groups is partially driven by the differential abundances of members of the Chitinophagaceae family. It may be observed that functional differences in otherwise similar soil aggregates can be largely attributed to differences in resource availability, rather than to the presence or absence of particular taxonomic groups.

Physico-chemical protection, rather than biochemical composition, governs the responses of soil organic carbon decomposition to nitrogen addition in a temperate agroecosystem

“…Moreover, N additon may also change the biomass, composition, physiology, and activity of soil microbial community (Cusack et al, 2011;Eisenlord et al, 2013;Leff et al, 2015;Riggs and Hobbie, 2016), which could lead to reduced SOC turnover. It should be noted different aggregation fractions of SOC not only differ in the in microbial accessibility due to different levels of physico-chemical protection, but also harbor different microbial communities (Bailey et al, 2013) which can be differentially affected by N addition (Freedman et al, 2015;Leff et al, 2015). Pinpointing the mechanisms of the heterogeneous reponses of SOC decomposition to N addition among soil aggregate fractions awaits further investigation, particularly on the microbial community composition and activity of different aggregate fractions.…”

Microbial Community Structure and Function of Soil Following Ecosystem Conversion from Native Forests to Teak Plantation Forests

“…Soil enzyme activities were used as additional proxies of ecosystem functions (Bowker et al, 2011; Bailey et al, 2013). EAA serve as functional indicators and variation in production are often linked to changes in microbial community structure or activities, which are also impacted by resource inputs.…”

Single‐cell sequencing unveils the lifestyle and CRISPR‐based population history of Hydrotalea sp. in acid mine drainage

“…Chitinophagaceae (phylum Bacteroidetes) comprises a ubiquitous bacterial family that was recently described in soil (Bailey, Fansler, Stegen, & McCue, 2013;Lv, Wang, Chen, You, & Qiu, 2016), freshwater (Leite et al, 2016;Siddiqi & Im, 2016), a hypersaline lake (Vavourakis et al, 2016), hot springs (Hanada, Tamaki, Nakamura, & Kamagata, 2014), maize roots (Gao et al, 2016) and human tumours (Lo et al, 2015). This is a clade with strong taxonomic support, even though few genomes have been fully sequenced to date.…”