Project description:Full title: Environmental transcriptome analysis of LfeRT32a in its natural microbial community comparing the biofilm and planktonic modes of life. Extreme acidic environments are characterized among other features by the high metal content and the lack of nutrients (oligotrophy). Macroscopic biofilms and filaments usually grow on the water-air interface or under the stream attached to solid substrates (streamers). In the Tinto River (Spain), brown filaments develop under the water stream where the Gram-negative iron-oxidizing bacteria Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans are abundant. Both microorganisms play a critical role in bioleaching processes for industrial (biominery) and environmental applications (acid mine drainage, bioremediation). The aim of this study was to investigate the physiological differences between the free living (planktonic) and the sessile (biofilm associated) lifestyles of L. ferrooxidans as part of a natural extremely acidophilic community.
Project description:October 2013 surface seawater collected from Monterey Bay was incubated with 1 micromolar 13C labeled glucose, starch, acetate, lipids, protein, or amino acids for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots.
Project description:October 2013 surface seawater collected from Monterey Bay was incubated with 1 micromolar 13C labeled glucose, starch, acetate, lipids, protein, or amino acids for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots. Two Chips for fluorescence, and 15 Chips for different substrates from samples incubated for 12 or 36 hours.
Project description:Total bacterial DNA was isolated from water and sediment samples from a local watershed and 16S rRNA sequences were analyzed using the Illumina MiSeq v3 platform in order to generate snapshots of bacterial community profiles. A total of 56 samples were collected that represent water and sediment samples from 14 sample sites over two different time points (November 18 and 25, 2011).
Project description:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples.
Project description:The increased urban pressures are often associated with specialization of microbial communities. Microbial communities being a critical player in the geochemical processes, makes it important to identify key environmental parameters that influence the community structure and its function.In this proect we study the influence of land use type and environmental parameters on the structure and function of microbial communities. The present study was conducted in an urban catchment, where the metal and pollutants levels are under allowable limits. The overall goal of this study is to understand the role of engineered physicochemical environment on the structure and function of microbial communities in urban storm-water canals. Microbial community structure was determined using PhyoChio (G3) Water and sediment samples were collected after a rain event from Sungei Ulu Pandan watershed of >25km2, which has two major land use types: Residential and industrial. Samples were analyzed for physicochemical variables and microbial community structure and composition. Microbial community structure was determined using PhyoChio (G3)
Project description:Total bacterial DNA was isolated from water and sediment samples from a local watershed and 16S rRNA sequences were analyzed using the Illumina MiSeq v3 platform in order to generate snapshots of bacterial community profiles.
Project description:To gain improved temporal, spatial and phylogenetic resolution of marine microbial communities, in this study we expanded the original prototype genome proxy array (an oligonucleotide microarray targeting marine microbial genome fragments and genomes), evaluated it against metagenomic sequencing, and applied it to time series samples from the Monterey Bay long term ecological research site. The expanded array targeted 268 microbial genotypes (vs. 14 in the original prototype) across much of the known diversity of cultured and uncultured marine microbes. The target abundances measured by the genome proxy array were highly correlated to pyrosequence-based abundances (linear regression R2 = 0.85-0.91, p<0.0001). Fifty-seven samples from ~4-years in Monterey Bay were examined with the array, spanning the photic zone (0m), the base of the surface mixed layer (30m), and the subphotic zone (200m). A significant portion of the expanded genome proxy array’s targets showed signal (95 out of 268 targets present in ≥ 1 sample). The multi-year community survey showed the consistent presence of a core group of common and abundant targeted taxa at each depth in Monterey Bay, higher variability among shallow than deep samples, and episodic occurrences of more transient marine genotypes. The abundance of the most dominant genotypes peaked after strong episodic upwelling events. The genome-proxy array’s ability to track populations of closely-related genotypes indicated population shifts within several abundant target taxa, with specific populations in some cases clustering by depth or oceanographic season. Although 51 cultivated organisms were targeted (representing 19% of the array) the majority of targets detected and of total target signal (85% and ~92%, respectively) were from uncultivated lineages, often those derived from Monterey Bay. The array provided cost-effective (~$15 per array, for construction and use) insights into the natural history of uncultivated lineages in the wild. To gain improved temporal, spatial and phylogenetic resolution of marine microbial communities, in this study we expanded the original prototype genome proxy array (an oligonucleotide microarray targeting marine microbial genome fragments and genomes), evaluated it against metagenomic sequencing, and applied it to time series samples from the Monterey Bay long term ecological research site. The expanded array targeted 268 microbial genotypes (vs. 14 in the original prototype) across much of the known diversity of cultured and uncultured marine microbes. The target abundances measured by the genome proxy array were highly correlated to pyrosequence-based abundances (linear regression R2 = 0.85-0.91, p<0.0001). Fifty-seven samples from ~4-years in Monterey Bay were examined with the array, spanning the photic zone (0m), the base of the surface mixed layer (30m), and the subphotic zone (200m). A significant portion of the expanded genome proxy array’s targets showed signal (95 out of 268 targets present in ≥ 1 sample). The multi-year community survey showed the consistent presence of a core group of common and abundant targeted taxa at each depth in Monterey Bay, higher variability among shallow than deep samples, and episodic occurrences of more transient marine genotypes. The abundance of the most dominant genotypes peaked after strong episodic upwelling events. The genome-proxy array’s ability to track populations of closely-related genotypes indicated population shifts within several abundant target taxa, with specific populations in some cases clustering by depth or oceanographic season. Although 51 cultivated organisms were targeted (representing 19% of the array) the majority of targets detected and of total target signal (85% and ~92%, respectively) were from uncultivated lineages, often those derived from Monterey Bay. The array provided cost-effective (~$15 per array, for construction and use) insights into the natural history of uncultivated lineages in the wild.
2010-04-24 | GSE21502 | GEO
Project description:Planktonic bacterial and eukaryotic communities