Description: The sea-surface microlayer (SML) at the boundary between atmosphere and hydrosphere represents a demanding habitat for bacteria. Wind speed is a crucial but poorly studied factor for its physical integrity. Increasing atmospheric burden of CO2, as suggested for future climate scenarios, may particularly act on this habitat at the air-sea interface. We investigated the effect of increasing wind speeds and different pCO2 levels on SML microbial communities in a wind-wave tunnel, which offered the advantage of low spatial and temporal variability. We found that enrichment of bacteria in the SML occurred solely at a U10 wind speed of 〈=5.6 m/s in the tunnel and 〈=4.1 m/s in the Baltic Sea. High pCO2 levels further intensified the bacterial enrichment in the SML during low wind speed. In addition, low wind speed and pCO2 induced the formation of a distinctive bacterial community as revealed by 16S rRNA gene fingerprints and influenced the presence or absence of individual taxonomic units within the SML. We conclude that physical stability of the SML below a system-specific wind speed threshold induces specific bacterial communities in the SML entailing strong implications for ecosystem functioning by wind-driven impacts on habitat properties, gas-exchange and matter cycling processes.

Description: We investigated the occurrence, spatial, and vertical distributions of 63 pharmaceutical compounds and six artificial sweeteners from the sea surface microlayer (SML) to five different depths (0 cm, 20 cm, 50 cm, 100 cm, and 150 cm) of the corresponding underlying waters in four stations of the North Sea. One station is a coastal area (Jade Bay), one station is an estuary (Bremerhaven), and the other two stations (NS_7 and NS_8) are open coastal waters. We will refer to each environment with the name in brackets throughout this publication. We collected seawater samples vertically from these stations and analyzed them using ultra-performance liquid chromatography - triple quadrupole mass spectrometry in tandem with ionization spray (UPLC-QqQMS/MS) (Bruker EVOQ Elite system Bruker, USA) at the Department of Physical Chemistry, University of Cádiz.

Description: Twenty-four strains of marine Roseobacter clade bacteria were isolated from macroalgae and investigated for the production of quorum-sensing autoinducers, N-acylhomoserine lactones (AHLs). GC/MS analysis of the extracellular metabolites allowed us to evaluate the release of other small molecules as well. Nineteen strains produced AHLs, ranging from 3-OH-C10:0-HSL (homoserine lactone) to (2E,11Z)-C18:2-HSL, but no specific phylogenetic or ecological pattern of individual AHL occurrence was observed when cluster analysis was performed. Other identified compounds included indole, tropone, methyl esters of oligomers of 3-hydroxybutyric acid, and various amides, such as N-9-hexadecenoylalanine methyl ester (9-C16:1-NAME), a structural analogue of AHLs. Several compounds were tested for their antibacterial and antialgal activity on marine isolates likely to occur in the habitat of the macroalgae. Both AHLs and 9-C16:1-NAME showed high antialgal activity against Skeletonema costatum, whereas their antibacterial activity was low.

Description: Marine sponges (Phylum Porifera) are globally distributed within marine and freshwater ecosystems. In addition, sponges host dense and diverse prokaryotic communities, which are potential sources of novel bioactive metabolites and other complex compounds. Those sponge-derived natural products can span a broad spectrum of bioactivities, from antibacterial and antifungal to antitumor and antiviral compounds. However, most analyses concerning sponge-associated prokaryotes have mainly focused on conveniently accessible relatively shallow sampling locations for sponges. Hence, knowledge of community composition, host-relatedness and biotechnological potential of prokaryotic associations in temperate and cold-water sponges from greater depths (mesophotic to mesopelagic zones) is still scarce. Therefore, we analyzed the prokaryotic community diversity of four phylogenetically divergent sponge taxa from mesophotic to mesopelagic depths of Antarctic shelf at different depths and locations in the region of the South Shetland Islands using 16S rRNA gene amplicon-based sequencing. In addition, we predicted functional profiles applying Tax4Fun from metagenomic 16S rRNA gene data to estimate their biotechnological capability and possible roles as sources of novel bioactive compounds. We found indications that cold and deep-water sponges exhibit host-specific prokaryotic communities, despite different sampling sites and depths. Functional prediction analysis suggests that the associated prokaryotes may enhance the roles of sponges in biodegradation processes of xenobiotics and their involvement in the biosynthesis of secondary metabolites.

Description: Metabolism of 2,3-dihydroxypropane-1-sulfonate by marine bacteria Ersin Celik Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn 53121 Bonn Germany Michael Maczka Institut für Organische Chemie TU Braunschweig 38106 Braunschweig Germany Nils Bergen Institut für Chemie und Biologie des Meeres Universität Oldenburg 26129 Oldenburg Germany Thorsten Brinkhoff Institut für Chemie und Biologie des Meeres Universität Oldenburg 26129 Oldenburg Germany Stefan Schulz Institut für Organische Chemie TU Braunschweig 38106 Braunschweig Germany http://orcid.org/0000-0002-4810-324X Jeroen S. Dickschat Kekulé-Institut für Organische Chemie und Biochemie Rheinische Friedrich-Wilhelms-Universität Bonn 53121 Bonn Germany http://orcid.org/0000-0002-0102-0631 The uptake and conversion of the algal sulfoquinovose catabolite 2,3-dihydroxypropane-1-sulfonate by marine bacteria was studied in isotopic labelling experiments. Both enantiomers of the sulfoquinovose breakdown product 2,3-dihydroxypropane-1-sulfonate, an important sulfur metabolite produced by marine algae, were synthesised in a 34 S-labelled form and used in feeding experiments with marine bacteria. The labelling was efficiently incorporated into the sulfur-containing antibiotic tropodithietic acid and sulfur volatiles by the algal symbiont Phaeobacter inhibens , but not into sulfur volatiles released by marine bacteria associated with crustaceans. The ecological implications and the relevance of these findings for the global sulfur cycle are discussed. 2017 2919 2922 1 10.1039/rsc_crossmark_policy rsc.org true This document is Similarity Check deposited Supplementary Information Stefan Schulz (ORCID) Jeroen S. Dickschat (ORCID) The Royal Society of Chemistry has an exclusive publication licence for this journal Single-blind Received 14 February 2017; Accepted 15 March 2017; Advance Article published 22 March 2017; Version of Record published 5 April 2017 Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 http://dx.doi.org/10.13039/501100001659 SFB TR51 10.1039/C7OB00357A 20171121163610 http://xlink.rsc.org/?DOI=C7OB00357A http://pubs.rsc.org/en/content/articlepdf/2017/OB/C7OB00357A Adv. Lipid Res. Benson 1 387 1963 10.1016/B978-1-4831-9937-5.50016-8 Z. Naturforsch., C: J. Biosci. Datz 36 856 1981 10.1515/znc-1981-9-1027 Lipids Gage 27 632 1992 10.1007/BF02536123 Biochem. Biophys. Res. Commun. Sato 470 123 2016 10.1016/j.bbrc.2016.01.006 Biochem. Soc. Trans. Harwood 7 440 1979 10.1042/bst0070440 Org. Biomol. Chem. Dickschat 13 1954 2015 10.1039/C4OB02407A Appl. Environ. Microbiol. Roy 69 6434 2003 10.1128/AEM.69.11.6434-6441.2003 Nature Denger 507 114 2014 10.1038/nature12947 Proc. Natl. Acad. Sci. U. S. A. Durham 112 453 2015 10.1073/pnas.1413137112 Nature Croft 438 90 2005 10.1038/nature04056 FEMS Microbiol. Lett. Denger 328 39 2012 10.1111/j.1574-6968.2011.02477.x Microbiology Mayer 156 1556 2010 10.1099/mic.0.037580-0 Microbiology Rein 151 737 2005 10.1099/mic.0.27548-0 Microbiology Denger 156 967 2010 10.1099/mic.0.034736-0 J. Bacteriol. Denger 191 5648 2009 10.1128/JB.00569-09 Microbiology Mikosch 145 1153 1999 10.1099/13500872-145-5-1153 Biochem. J. Denger 394 657 2006 10.1042/BJ20051311 Biochemistry White 25 5304 1986 10.1021/bi00366a047 Biochem. J. Ruff 369 275 2003 10.1042/bj20021455 Microbiology Weinitschke 153 3055 2007 10.1099/mic.0.2007/009845-0 J. Antibiot. Kintaka 37 1294 1984 10.7164/antibiotics.37.1294 ChemBioChem Dickschat 11 417 2010 10.1002/cbic.200900668 Org. Biomol. Chem. Dickschat 13 1954 2015 10.1039/C4OB02407A Nat. Chem. Seyedsayamdost 3 331 2011 10.1038/nchem.1002 Proc. Natl. Acad. Sci. U. S. A. Wilson 113 1630 2016 10.1073/pnas.1518034113 Appl. Environ. Microbiol. Geng 74 1535 2008 10.1128/AEM.02339-07 Chem. Commun. Brock 50 5487 2014 10.1039/c4cc01924e mBio Wang 7 e02118 2016 Org. Biomol. Chem. Brock 12 4318 2014 10.1039/c4ob00719k Beilstein J. Org. Chem. Brock 9 942 2013 10.3762/bjoc.9.108 Nature Reisch 473 208 2011 10.1038/nature10078 Beilstein J. Org. Chem. Rinkel 11 2493 2015 10.3762/bjoc.11.271 Tetrahedron Schulz 60 3863 2004 10.1016/j.tet.2004.03.005 Appl. Environ. Microbiol. Rao 73 7844 2007 10.1128/AEM.01543-07 Science Todd 315 666 2007 10.1126/science.1135370 Nat. Rev. Microbiol. Curson 9 849 2011 10.1038/nrmicro2653 Curr. Opin. Chem. Biol. Johnston 31 58 2016 10.1016/j.cbpa.2016.01.011 ISME J. Thole 6 2229 2012 10.1038/ismej.2012.62