Vulnerability of reef-building corals towards global change

Global warming is leading to large-scale coral bleaching and mass mortality, but also to increases in tropical storms' frequency and intensity. Storms allow fragmentation of reef-building corals and can lead to near-shore salinity reduction which, combined with ocean warming, will aggravate coral distress. In order to assess the susceptibility of different coral species to these environmental stressors, small fragments of nine coral species of the Indo-Pacific region were exposed to different thermal (26°C, 30°C, 32°C) and hyposaline (26°C-33psu, 30°C-33psu, 26°C-20psu, 30°C-20psu) experimental treatments for 60 days. Several parameters were assessed at different levels of biological organization: at the organism level (total and partial mortality, and coral condition based in bleaching levels), physiological level (growth rate and regeneration rate of artificially inflicted lesions), and molecular level (superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and lipid peroxidation (LPO)). Also, in order to test two different approaches to be applied in the monitoring of the effects of heat stress, some parameters were combined in integrated biomarker response indices, either in a molecular approach, approach A, using GST, CAT, LPO, and SOD, or in an approach that integrates the molecular, physiological and organism levels, approach B, using GST, CAT, LPO, SOD, partial mortality, and growth rate. Results indicate that Pocillopora damicornis and Stylophora pistillata were the most vulnerable at 30°C. Psammocora contigua, Turbinaria reniformis, and Galaxea fascicularis were the most tolerant species at 32°C. The species P. contigua and G. fascicularis were the most tolerant to low salinity (26°C-20psu). The species G. fascicularis was the only one capable of surviving the combined effect of high temperature and low salinity (30°C-20psu). Approach B, the most integrative approach, was considered the most adequate for evaluating the health of reef corals since it better discriminated the stress suffered by the tested species.MAREUCIBI

Natural Product Genomics and Metabolomics of Marine Bacteria

Marine organisms are a treasure trove for the discovery of novel natural products, and, thus, marine natural products have been a focus of interest for researchers for decades. Some marine bacteria are prolific producers of natural products, occurring either free-living or, as recently shown, in symbiosis with marine animals. Recent advances in DNA sequencing have led to an enormous increase in published bacterial genomes and bioinformatics tools to analyze natural product biosynthetic potential by various “genome mining” approaches. Similarly, analytical NMR and MS methods for the characterization and comparison of metabolomes of natural product producers have advanced. Novel interdisciplinary approaches combine genomics and metabolomics data for accelerated and targeted natural product discovery. This Special Issue invites articles from both genomics- and metabolomics-driven studies on marine bacteria with a focus on natural product discovery and characterization. We particularly welcome articles that combine genomics and metabolomic approaches for the dereplication and characterization of marine bacterial natural products

Large space structures and systems in the space station era: A bibliography with indexes (supplement 05)

Bibliographies and abstracts are listed for 1363 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1991 and July 31, 1992. Topics covered include technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion and solar power satellite systems