Project description:18S V9 region - Tropics to poles: Diversity and composition of coastal eukaryotic marine microalgae communities across five ecoregions.
| PRJNA1072270 | ENA
Project description:Microbial eukaryotic 18S v4 region amplicon
| PRJNA646537 | ENA
Project description:SMART: Resource partitioning by Specialization in marine parasites. Coastal microalgae bloom, V4 region.
Project description:Diatoms are eukaryotic microalgae that contain genes from various sources, including bacteria and the secondary endosymbiotic host. Due to this unique combination of genes, diatoms are taxonomically and functionally distinct from other algae and vascular plants and confer novel metabolic capabilities. Based on the genome annotation, we performed a genome-scale metabolic network reconstruction for the marine diatom Phaeodactylum tricornutum. Due to their endosymbiotic origin, diatoms possess a complex chloroplast structure which complicates the prediction of subcellular protein localization. Based on previous work we implemented a pipeline that exploits a series of bioinformatics tools to predict protein localization. The manually curated reconstructed metabolic network iLB1027_lipid accounts for 1,027 genes associated with 4,456 reactions and 2,172 metabolites distributed across six compartments. To constrain the genome-scale model, we determined the organism specific biomass composition in terms of lipids, carbohydrates, and proteins using Fourier transform infrared spectrometry. Our simulations indicate the presence of a yet unknown glutamine-ornithine shunt that could be used to transfer reducing equivalents generated by photosynthesis to the mitochondria. The model reflects the known biochemical composition of P. tricornutum in defined culture conditions and enables metabolic engineering strategies to improve the use of P. tricornutum for biotechnological applications.
Project description:DNA oligonucleotide microarrays were designed with 307 probes for 96 internal transcribed spacer (ITS1, located between 18S and 26S rRNA genes) sequences of known species and strains from the genus Pseudo-nitzschia (Bacillariophyceae). In addition, microarrays also carried 1893 probes targeting ITS1 aequences of marine Crenarchaeota and Alphaproteobacteria of SAR11 clade. In order to assign microarray profiles to Pseudo-nitzschia ribotypes and species and to 'train' the data analysis system, we grew cultures of Pseudo-nitzschia in the laboratory with identities confirmed through rDNA sequence analysis. In total, 9 cultures and 35 environmental water samples were hybridized to microarrays, in some cases, in duplicate or triplicate. Analysis of microarray data allowed us to identify and map Pseudo-nitzschia spp. in the coastal waters along Washington and Oregon coast of the Eastern Pacific Ocean, and to observe seasonal changes in diatom community composition.
2012-06-01 | GSE27141 | GEO
Project description:A comparison of two gene regions for assessing community composition of eukaryotic marine microalgae from coastal ecosystems.
Project description:In estuaries and coastal areas, salinity regimes vary with river discharge, seawater evaporation, morphology of the coastal waterways, and dynamics of marine water mixing. Therefore, microalgae have to respond to salinity variations at various time scales, from daily to annual cycling. They might also adapt to physical alteration that might induce loss of connectivity and enclosure of water bodies. Here we integrate physiological-based assays, morphological plasticity with functional genomics approach to examine the regulatory change that occur during the acclimation to salinity in an estuary diatom, Thalassiosira weissflogii. We found that this diatom respond to salinity (i.e. 21, 28 and 35 psu) with minute adjustments of its physiology (i.e., carbon and silicon metabolisms, pigments concentration and photosynthetic parameters). In contrast after short- (~ 5 generations) or long-term (~ 700 generations) culture at the different salinity we found a large transcriptome reprogramming. With most of the genes being down-regulated in long-term, and only a few genes in common between short and long term experiments.