Presence of an unusual 17α,21β(H)-bacteriohopanetetrol in Holocene sediments from Ace Lake (Antarctica)

Author Posting. © Elsevier B.V., 2008. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Organic Geochemistry 39 (2008): 1029-1032, doi:10.1016/j.orggeochem.2008.01.008.Whilst investigating the intact biohopanoid (bacteriohopanepolyol, BHP) distribution in Holocene sediments from Ace Lake (Antarctica), we have identified the presence of ab- bacteriohopanetetrol in sediments aged up to 9400 years BP. To our knowledge, this is the first time that an intact polyfunctionalised BHP with the “geological” 17α,21β(H) configuration has been identified in a sediment. Previously, this structure has only been observed in species of the nitrogen fixing bacterium Frankia. Its presence here in the sedimentary environment has implications for the interpretation of hopanoid ββ/αβ ratios in the geological record.This work was supported by grants from the Australian Antarctic Science Advisory Committee (1166 to J.V.) and the Netherlands Organization for Scientific Research (NWO; 851.20.006 to J.S.S.D. and NWO-VENI grant 016.051.014 to M.J.L.C.) We gratefully acknowledge the NERC for funding (HMT) and The Science Research Infrastructure Fund (SRIF) from HEFCE for funding the purchase of the Thermo Electron Finnigan LCQ ion trap mass spectrometer

Anaerobic ammonium-oxidising bacteria: A biological source of the bacteriohopanetetrol stereoisomer in marine sediments

Bacterially-derived bacteriohopanepolyols (BHPs) are abundant, well preserved lipids in modern and paleo-environments. Bacteriohopanetetrol (BHT) is a ubiquitously produced BHP while its less common stereoisomer (BHT isomer) has previously been associated with anoxic environments; however, its biological source remained unknown. We investigated the occurrence of BHPs in Golfo Dulce, an anoxic marine fjord-like enclosure located in Costa Rica. The distribution of BHT isomer in four sediment cores and a surface sediment transect closely followed the distribution of ladderane fatty acids, unique biomarkers for bacteria performing anaerobic ammonium oxidation (anammox). This suggests that BHT isomer and ladderane lipids likely shared the same biological source in Golfo Dulce. This was supported by examining the BHP lipid compositions of two enrichment cultures of a marine anammox species ('. Candidatus Scalindua profunda'), which were found to contain both BHT and BHT isomer. Remarkably, the BHT isomer was present in higher relative abundance than BHT. However, a non-marine anammox enrichment contained only BHT, which explains the infrequence of BHT isomer observations in terrestrial settings, and indicates that marine anammox bacteria are likely responsible for at least part of the environmentally-observed marine BHT isomer occurrences. Given the substantially greater residence time of BHPs in sediments, compared to ladderanes, BHT isomer is a potential biomarker for past anammox activity

Development of monolithic dye sensitized solar cell fabrication with polymer-based counter electrode

Fabrication of monolithic dye sensitized solar cell (DSSC) has been developed by using a poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) polymer as counter electrode. The number of layers and annealing temperature of PEDOT:PSS layers which is prepared by screen printing technique has been investigated to find the optimum performance of monolithic DSSC. The best performance of monolithic DSSC with 0.61 V open circuit voltage, 1.26 mA short circuits current, and 1.77% efficiency were resulted in 3 layers of PEDOT: PSS with annealing temperature at 120°C. The conductivity of counter electrode layer increase with the increasing of number of polymer layer, produce a high short circuit current. Otherwise, increasing the annealing temperature of PEDOT:PSS layer increases the conductivity of counter electrode layer, but decreases the Isc value

Poly(2-ethyl-2-oxazoline) coating of additively manufactured biodegradable porous iron

Additively manufacturing of porous iron offers a unique opportunity to increase its biodegradation rate by taking advantage of arbitrarily complex porous structures. Nevertheless, achieving the required biodegradation profile remains challenging due to the natural passivation of iron that decrease the biodegradation rate. Moreover, the biocompatibility of iron is reported to be limited. Here, we address both challenges by applying poly(2-ethyl-2-oxazoline) coating to extrusion-based 3D printed porous iron. We characterized the specimens by performing in vitro biodegradation, electrochemical measurements, time-dependent mechanical tests, and in vitro cytocompatibility assays. The coated porous iron exhibited a biodegradation rate that was 2.6× higher than that of non-coated counterpart and maintained the bone-mimicking mechanical properties throughout biodegradation. Despite the formation of dense biodegradation products, the coating ensured a relatively stable biodegradation (i.e., 17% reduction in the degradation rate between days 14 and 28) as compared to that of non-coated specimens (i.e., 43% drop). Furthermore, the coating could be identified even after biodegradation, demonstrating the longevity of the coating. Finally, the coated specimens significantly increased the viability and supported the attachment and growth of preosteoblasts. Our results demonstrate the great potential of poly(2-ethyl-2-oxazoline) coating for addressing the multiple challenges associated with the clinical adoption of porous iron.Biomaterials & Tissue BiomechanicsTeam Peyman TaheriTeam Arjan Mo

World Octopus Fisheries

153 pages, 97 figures, 10 tables, 2 appendixesRecent studies have shown that coastal and shelf cephalopod populations have increased globally over the last six decades. Although cephalopod landings are dominated by the squid fishery, which represents nearly 80% of the worldwide cephalopod catches, octopuses and cuttlefishes represent ∼10% each. Total reported global production of octopuses over the past three decades indicates a relatively steady increase in catch, almost doubling from 179,042 t in 1980 to 355,239 t in 2014. Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited. More than twenty described octopus species are harvested from some 90 countries worldwide. The current review describes the major octopus fisheries around the globe, providing an overview of species targeted, ecological and biological features of exploited stocks, catches and the key aspects of managementIGG has been supported by the Japan Science and Technology Agency (Grants J130000263 and AS2715164U). RV has been supported by the Spanish Ministry of Education and Culture (Grant PRX17/00090), Spanish Ministry of Science, Innovation and Universities (OCTOSET project, RTI2018-097908-B-I00, MCIU/AEI/FEDER, EU) and by the Direcció General de Pesca i Afers Marítims, Generalitat de Catalunya. FAFA was supported by a predoctoral fellowship of the MINECO (BES-2013-063551) and an Irish Research Council - Government of Ireland Postdoctoral Fellowship (Ref. GOIPD/2019/460)Peer reviewe

Significant Natural Product Biosynthetic Potential of Actinorhizal Symbionts of the Genus Frankia, as Revealed by Comparative Genomic and Proteomic Analyses▿

Bacteria of the genus Frankia are mycelium-forming actinomycetes that are found as nitrogen-fixing facultative symbionts of actinorhizal plants. Although soil-dwelling actinomycetes are well-known producers of bioactive compounds, the genus Frankia has largely gone uninvestigated for this potential. Bioinformatic analysis of the genome sequences of Frankia strains ACN14a, CcI3, and EAN1pec revealed an unexpected number of secondary metabolic biosynthesis gene clusters. Our analysis led to the identification of at least 65 biosynthetic gene clusters, the vast majority of which appear to be unique and for which products have not been observed or characterized. More than 25 secondary metabolite structures or structure fragments were predicted, and these are expected to include cyclic peptides, siderophores, pigments, signaling molecules, and specialized lipids. Outside the hopanoid gene locus, no cluster could be convincingly demonstrated to be responsible for the few secondary metabolites previously isolated from other Frankia strains. Few clusters were shared among the three species, demonstrating species-specific biosynthetic diversity. Proteomic analysis of Frankia sp. strains CcI3 and EAN1pec showed that significant and diverse secondary metabolic activity was expressed in laboratory cultures. In addition, several prominent signals in the mass range of peptide natural products were observed in Frankia sp. CcI3 by intact-cell matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS). This work supports the value of bioinformatic investigation in natural products biosynthesis using genomic information and presents a clear roadmap for natural products discovery in the Frankia genus

Not Available

Not AvailableRecent studies have shown that coastal and shelf cephalopod populations have increased globally over the last six decades. Although cephalopod landings are dominated by the squid fishery, which represents nearly 80% of the worldwide cephalopod catches, octopuses and cuttlefishes represent ∼10% each. Total reported global production of octopuses over the past three decades indicates a relatively steady increase in catch, almost doubling from 179,042 t in 1980 to 355,239 t in 2014. Octopus fisheries are likely to continue to grow in importance and magnitude as many finfish stocks are either fully or over-exploited. More than twenty described octopus species are harvested from some 90 countries worldwide. The current review describes the major octopus fisheries around the globe, providing an overview of species targeted, ecological and biological features of exploited stocks, catches and the key aspects of management.Not Availabl