Project description:This data is a case study done in the context of developing methods for assessing the taxonomic composition of microbial communities using metaproteomics. For this study with analyzed phototrophic biomats from two Soda Lakes in the Canadian Rocky Mountains using metaproteomics. For protein identification we generated a metagenome from which we predicted and annotated the protein sequences used to analyze the metaproteomes. The database is available in this PRIDE submission. Lake1 refers to Goodenough Lake (GEM, 51°19'47.64"N 121°38'28.90"W) and Lake2 referes to Last Chance Lake (LCM, 51°19'39.3" N 121°37'59.3"W).
Project description:In this study we used metaproteomics to discern the metabolism and physiology of the microorganisms occurring in the phototrophic mats of four soda lakes in the interior of British Columbia, Canada. Binned and assembled metagenomes were used as the database for protein identification.
Project description:Haloalkaliphilic microorganisms are double extremophiles functioning optimally at high salinity and pH. Their typical habitats are soda lakes, representing geologically ancient ecosystems which are still widespread on Earth and supposedly harbor relict microbial communities. We compared metabolic features and their genomic determinants in two strains of a single natronophilic species Dethiobacter alkaliphilus, the only cultured representative of “Dethiobacteria” class within Bacillota phylum. The strains of D. alkaliphilus were previously isolated from geographically remote Mongolian and Kenyan soda lakes. The type strain AHT1T was described as a facultatively chemolithoautotrophic sulfidogen reducing or disproportionating sulfur or thiosulfate, while strain Z-1002 was isolated as a chemolithoautotrophic iron reducer. Here, we uncovered iron reducing ability of strain AHT1T, as well as the capability of strain Z-1002 for thiosulfate reduction and anaerobic Fe(II) oxidation. Key catabolic processes sustaining the growth of both strains appeared to fit the geochemical settings of two contrasting natural alkaline environments, sulfur-enriched soda lakes and iron-enriched serpentinites. This assumption was supported by meta-analysis of publicly available Dethiobacterial metagenomes, as well as by the enrichment of a novel phylotype from a deep subsurface non-serpentinizing slightly alkaline water after its amendment with an Fe(III) mineral. Genome analysis of D. alkaliphilus strains revealed that the most probable determinants of iron and sulfur redox transformations in the organism are multiheme c-type cytochromes. Their phylogeny reconstruction showed that sulfur and thiosulfate respiration is most probably provided by evolutionary early forms of unconventional octaheme tetrathionate and sulfite reductases sharing a root with structurally similar group of OmhA/OcwA Fe(III)-reductases. Large sets of other multihemes are likely to provide Fe(III) reduction in both strains. Also, several different, yet phylogenetically related, determinants of anaerobic Fe(II) oxidation were identified in Z-1002 genome, and the oxidation process was further experimentally proven. Considering these results and phylogenetic relatedness of D. alkaliphilus’s sulfur reductases with Fe(III) reducing cytochromes, but not with archetypal bacterial sulfur/thiosulfate reductases, we suggest that sustaining high variation of multiheme cytochromes is an effective adaptive strategy to occupy geochemically contrasting alkaline anaerobic environments. We further propose that sulfur-enriched soda lakes are secondary habitats for D. alkaliphilus comparing to Fe-rich serpentinites, and discuss the evolutionary traits which might occur in prokaryotes on a crucial junction of the biosphere’s history, when intensification of the sulfur cycle outweighed the global significance of the iron cycle.
Project description:A new haloalkaliphilic species of Wenzhouxiangella, strain AB-CW3 was isolated from a system of alkaline soda lakes in the Kulunda Steppe. Its complete, circular genome was assembled from combined nanopore and illumina sequencing and its proteome was determined for three different experimental conditions: growth on Staphylococcus cells, casein, or peptone. AB-CW3 is an aerobic bacterium feeding mainly on proteins and peptides.