Elevated temperature alters proteomic responses of individual organisms within a biofilm community

Abstract

Microbial communities that underpin global biogeochemical cycles will likely be influenced by elevated temperature associated with environmental change. Here, we test an approach to measure how elevated temperature impacts the physiology of individual microbial groups in a community context, using a model microbial-based ecosystem. The study is the first application of tandem mass tag (TMT)-based proteomics to a microbial community. We accurately, precisely and reproducibly quantified thousands of proteins in biofilms growing at 40, 43 and 46 1C. Elevated temperature led to upregulation of proteins involved in amino-acid metabolism at the level of individual organisms and the entire community. Proteins from related organisms differed in their relative abundance and functional responses to temperature. Elevated temperature repressed carbon fixation proteins from two Leptospirillum genotypes, whereas carbon fixation proteins were significantly upregulated at higher temperature by a third member of this genus. Leptospirillum group III bacteria may have been subject to viral stress at elevated temperature, which could lead to greater carbon turnover in the microbial food web through the release of viral lysate. Overall, these findings highlight the utility of proteomics-enabled community-based physiology studies, and provide a methodological framework for possible extension to additional mixed culture and environmental sample analyses.

Diversity and distribution of autotrophic microbial community along environmental gradients in grassland soils on the Tibetan Plateau

“…The different response to elevation suggest a niche differentiation in autotrophic microbial communities. The niche differentiation, which has been observed in a biofilm (Mosier et al 2015), could provide ecological insurance for microbial autotrophs under the harsh environments.…”

Ecology and biogeochemistry of cyanobacteria in soils, permafrost, aquatic and cryptic polar habitats

“…For instance, a recent study has assessed the effect of elevated temperatures on proteomic responses of individual organisms within a biofilm community (Mosier et al 2014). An application of these methods would produce insights into cyanobacteria in cryptic niches.…”

Proteogenomic analyses indicate bacterial methylotrophy and archaeal heterotrophy are prevalent below the grass root zone

“…An important motivation for recovery of genomes from the metagenomes is that protein sequences can be predicted in organism context and used in mass spectrometry studies to identify proteins that are highly abundant in microbial cells (Brooks et al, 2015; Mosier et al, 2015). This information, in combination with metabolite concentrations measured through the soil profile, enables identification of the organisms, pathways and spatial distribution of carbon turnover processes at the time of sample collection.…”