Search

Microbial communities often exhibit incredible taxonomic diversity, raising questions regarding the mechanisms enabling species coexistence and the role of this diversity in community functioning. On the one hand, many coexisting but taxonomically distinct microorganisms can encode the same energy-yielding metabolic functions, and this functional redundancy contrasts with the expectation that species should occupy distinct metabolic niches. On the other hand, the identity of taxa encoding each function can vary substantially across space or time with little effect on the function, and this taxonomic variability is frequently thought to result from ecological drift between equivalent organisms. Here, we synthesize the powerful paradigm emerging from these two patterns, connecting the roles of function, functional redundancy and taxonomy in microbial systems. We conclude that both patterns are unlikely to be the result of ecological drift, but are inevitable emergent properties of open microbial systems resulting mainly from biotic interactions and environmental and spatial processes.

Motivation Networks are used to relate topological structure to system dynamics and function, particularly in ecology systems biology. Network analysis is often guided or complemented by data-driven visualization. Hive one of many network visualizations, distinguish themselves as providing a general, consistent and coherent rule-based representation to motivate hypothesis development and testing. Results Here, we present HyPE, Hive Panel Explorer, a software application that creates a panel of interactive hive plots. HyPE enables network exploration based on user-driven layout rules and parameter combinations for simultaneous of multiple network views. We demonstrate HyPE’s features by exploring a microbial co-occurrence network constructed from forest soil microbiomes. Availability and implementation HyPE is available under the GNU license: https://github.com/hallamlab/HivePanelExplorer. Supplementary information Supplementary data are available at Bioinformatics online.

Here, we report the draft genome sequence for a new putative genus and species in the Methanoregulaceae family, whose members are generally slow-growing rod-shaped or coccoid methanogenic archaea. The information on this sediment-dwelling organism sheds light on the prokaryotes inhabiting isolated, deep, and extremely cold methane-rich environments.

Hahn, A. S. and Quideau, S. A. 2013. Shifts in soil microbial community biomass and resource utilization along a Canadian glacier chronosequence. Can. J. Soil Sci. 93: 305–318. We aimed to describe soil microbial community composition and functional diversity as well as determine the influence of Engelmann spruce (Picea engelmannii Parry) and yellow mountain avens (Dryas drummondii Rich.) on soil microbial community succession along a Canadian glacier chronosequence. Soil microbial composition and functional activity were assessed using phospholipid fatty acid (PLFA) analysis, substrate-induced respiration and enzyme activity analysis. To the best of our knowledge, this is the first study investigating peroxidase and phenol oxidase activities, indicators of fungal activity, along any glacial chronosequence. While no difference in soil microbial community composition along the chronosequence was detected from the PLFA analysis, both total microbial biomass and fungal activity increased with time since deglaciation. Yellow mountain avens, a plant known to support microbial nitrogen fixation in mid- and late successional stages, increased soil microbial biomass, although this effect took 40 yr after deglaciation to emerge. Additionally, significant correlations between microbial respiration of N-acetyl-glucosamine, protocatechuic acid, glucose and percent soil N were found along the chronosequence, indicating that the soil microbial community was influencing changes in the soil environment.

Background and Aims Ecosystem recovery following disturbance requires the reestablishment of key soil biogeochemical processes. This long-term 7 year study describes effects of organic material, moisture, and vegetation on soil microbial community development in the Athabasca Oil Sands Region of Western Canada. Methods Phospholipid fatty acid analysis was used to characterize and compare soil microbial community composition and development on reclaimed and natural forest sites. Additionally, we conducted a laboratory moisture manipulation experiment. Results The use of forest floor material as an organic amendment resulted in a greater percent cover of upland vegetation and placed the soil microbial community on a faster trajectory towards ecosystem recovery than did the use of a peat amendment. The soil microbial composition within the reclaimed sites exhibited a greater response to changes in moisture than did the soil microbial communities from natural sites. Conclusion Our research shows that the use of native organic amendment (forest floor) on reclaimed sites, and the associated establishment of native vegetation promote the development of soil microbial communities more similar to those found on natural forest sites. Additionally, soil microbial communities from natural sites may be more resistant to changes in soil moisture than those found on reclaimed sites.

Enhanced biological phosphorus removal (EBPR) relies on diverse but specialized microbial communities to mediate the cycling and ultimate removal of phosphorus from municipal wastewaters. However, little is known about microbial activity and dynamics in relation to process fluctuations in EBPR ecosystems. Here, we monitored temporal changes in microbial community structure and potential activity across each bioreactor zone in a pilot-scale EBPR treatment plant by examining the ratio of small subunit ribosomal RNA (SSU rRNA) to SSU rRNA gene (rDNA) over a 120 day study period. Although the majority of operational taxonomic units (OTUs) in the EBPR ecosystem were rare, many maintained high potential activities based on SSU rRNA : rDNA ratios, suggesting that rare OTUs contribute substantially to protein synthesis potential in EBPR ecosystems. Few significant differences in OTU abundance and activity were observed between bioreactor redox zones, although differences in temporal activity were observed among phylogenetically cohesive OTUs. Moreover, observed temporal activity patterns could not be explained by measured process parameters, suggesting that other ecological drivers, such as grazing or viral lysis, modulated community interactions. Taken together, these results point towards complex interactions selected for within the EBPR ecosystem and highlight a previously unrecognized functional potential among low abundance microorganisms in engineered ecosystems.

A revolution is unfolding in microbial ecology where petabytes of ‘multi-omics’ data are produced using next generation sequencing and mass spectrometry platforms. This cornucopia of biological information has enormous potential to reveal the hidden metabolic powers of microbial communities in natural and engineered ecosystems. However, to realize this potential, the development of new technologies and interpretative frameworks grounded in ecological design principles are needed to overcome computational and analytical bottlenecks. Here we explore the relationship between microbial ecology and information science in the era of cloud-based computation. We consider microorganisms as individual information processing units implementing a distributed metabolic algorithm and describe developments in ecoinformatics and ubiquitous computing with the potential to eliminate bottlenecks and empower knowledge creation and translation.