The Southern Ocean contributes substantially to the global biological carbon pump (BCP). Salps in the Southern Ocean, in particular Salpa thompsoni, are important grazers that produce large, fast-sinking fecal pellets. Here, we quantify the salp bloom impacts on microbial dynamics and the BCP, by contrasting locations differing in salp bloom presence/absence.
View Article and Find Full Text PDFDuring the last few decades, the study of microbial ecology has been enabled by molecular and genomic data. DNA sequencing has revealed the surprising extent of microbial diversity and how microbial processes run global ecosystems. However, significant gaps in our understanding of the microbial world remain, and one example is that microbial eukaryotes, or protists, are still largely neglected.
View Article and Find Full Text PDFBolidomonas is a genus of picoplanktonic flagellated algae that is closely related to diatoms. Triparma laevis, a species belonging to the Parmales, which are small cells with a siliceous covering, has been shown to form a monophyletic group with Bolidomonas. We isolated several novel strains of Bolidophyceae that have permitted further exploration of the diversity of this group using nuclear, plastidial and mitochondrial genes.
View Article and Find Full Text PDFPhotosynthetic eukaryotes have a critical role as the main producers in most ecosystems of the biosphere. The ongoing environmental metabarcoding revolution opens the perspective for holistic ecosystems biological studies of these organisms, in particular the unicellular microalgae that often lack distinctive morphological characters and have complex life cycles. To interpret environmental sequences, metabarcoding necessarily relies on taxonomically curated databases containing reference sequences of the targeted gene (or barcode) from identified organisms.
View Article and Find Full Text PDFJ Bacteriol
December 2012
Exiguobacterium antarcticum is a psychotropic bacterium isolated for the first time from microbial mats of Lake Fryxell in Antarctica. Many organisms of the genus Exiguobacterium are extremophiles and have properties of biotechnological interest, e.g.
View Article and Find Full Text PDFBackground: Mangroves are transitional coastal ecosystems in tropical and sub-tropical regions and represent biologically important and productive ecosystems. Despite their great ecological and economic importance, mangroves are often situated in areas of high anthropogenic influence, being exposed to pollutants, such as those released by oil spills.
Methodology/principal Findings: A microcosm experiment was conducted, which simulated an oil spill in previously pristine mangrove sediment.
Different human immunodeficiency virus type 1 (HIV-1) subtypes may have distinct biological, immunological and pathogenic properties. Efficiency of mother-to-child transmission (MTCT) may be among those properties, but few and controversial results have been described so far. In this study, 102 children born from HIV-1-infected mothers between 1998 and 2004 in the city of Rio Grande, Brazil were analyzed for potential risk factors associated with MTCT.
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