{"id":132,"date":"2017-07-18T15:06:36","date_gmt":"2017-07-18T14:06:36","guid":{"rendered":"http:\/\/www.oceanblogs.org\/m139\/?p=132"},"modified":"2017-07-18T15:22:04","modified_gmt":"2017-07-18T14:22:04","slug":"how-we-study-virus-diversity-in-the-deep-sea","status":"publish","type":"post","link":"https:\/\/www.oceanblogs.org\/m139\/2017\/07\/18\/how-we-study-virus-diversity-in-the-deep-sea\/","title":{"rendered":"How we study virus diversity in the deep sea"},"content":{"rendered":"

Dear interested reader, colleagues, friends and families,<\/p>\n

as mentioned in our last blog<\/a>, we took water samples across 4000\u00a0m depth using the CTD (conductivity, temperature, depth) \u2013 rosette sampler at our first station in the Caribbean Sea. Here, we are interested in the distribution of viruses, bacteria and protists (unicellular organisms) in the depth. The CTD system exhibits a set of sensors to derive physical parameters like the density of water, the oxygen content and salt concentrations in real time during the run down to the ground. These parameters are very helpful for us, as we choose the water depths for the sampling according to the profile of the different parameters.<\/p>\n

The chlorophyll-a-<\/em>maximum was reached in 60\u00a0m depth that is a zone with high density of photosynthetically active organisms (mainly algae). Chlorophyll a<\/em> is the major pigment of algae to make use of the light energy and to produce sugars and other substances. We expect the highest numbers of living organisms in this water layer. After measuring the different parameters on the CTD\u2019s way down, the water samples of the respective water layers were collected by the CTD on its way up. The results show that the temperature of 28\u00a0\u00b0C at the water surface decreases to 4\u00a0\u00b0C between 1000 and 1500\u00a0m depth and remains constant in the deep sea. In this depth and below, the cold water stores the most oxygen and has a salinity of 3.5\u00a0% (which means 35 g salt per litre). The density values do not change across depth, which indicates a relatively homogenous water body in the deep sea of the Caribbean Sea.<\/p>\n

The CTD system was ready to be activated during the run (Image 1, CTD tubes open). After boarding of the CTD on the RV Meteor (Image 2, CTD tubes closed), our scientists took the water samples of different depths for diverse purposes (Image\u00a03). For example, some water samples were mixed with iron chloride and filtered to obtain virus particles in the brownish-red precipitate on the filter (Image 4). The material will be subjected to modern DNA sequencing methods in Cologne to study virus diversity in the deep sea.<\/p>\n

Your M139 team<\/p>\n

–<\/p>\n

Liebe interessierte Leser, Kollegen, Freunde und liebe Familien,<\/p>\n

wie bereits im letzten Blog erw\u00e4hnt<\/a>, nahmen wir mithilfe des CTD-Kranzwassersch\u00f6pfers Wasserproben \u00fcber das 4000\u00a0m tiefe Vertikalprofil unserer ersten Beprobungsstation in der Karibik. Wir interessieren uns hier f\u00fcr die Verteilung von Viren, Bakterien und Protisten (Einzeller) in der Tiefe. Das CTD-System bietet viele Sensoren, mit denen physikalische Parameter wie die Dichte, Sauerstoff\u2013 und Salzkonzentrationen in Echtzeit w\u00e4hrend des Einsatzes ermittelt werden k\u00f6nnen. Diese Parameter sind sehr hilfreich, da wir die exakten Tiefen f\u00fcr die Probenahmen gem\u00e4\u00df dieser Werte ausw\u00e4hlen.<\/p>\n

Das Chlorophyll a<\/em> \u2013 Maximum wurde bei etwa 60\u00a0m Tiefe erreicht. Dies ist eine Zone mit hoher Dichte an photosynthetisch aktiven Organismen (vor allem Algen). Die Algen benutzen das Pigment Chlorophyll um Lichtenergie zu binden und Zucker und andere energiereiche Substanzen aus Kohlendioxid zu bilden. In der Tiefe des Chlorophyllmaximums erwarten wir auch die gr\u00f6\u00dften Anzahlen an lebenden Organismen. Nachdem die verschiedenen Parameter beim Abtauchen des CTD-Systems gemessen wurden, wird das auftauchende CTD-System f\u00fcr Probenahmen in den spezifischen Wasserschichten aktiviert. Die Auswertung der Ergebnisse ergab eine Temperatur von 28 \u00b0C an der Wasseroberfl\u00e4che, die bis auf 4 \u00b0C zwischen 1000\u00a0und 1500\u00a0m Tiefe abf\u00e4llt und bis in die Tiefsee konstant bleibt. In dieser Tiefe und darunter speichert das kalte Wasser den meisten Sauerstoff und weist einen Salzgehalt von 3.5 % (das entspricht 35 g Salz pro Liter) auf. Die Dichtewerte \u00fcber das gesamte Tiefenprofil \u00e4ndern sich nicht, was auf einen homogenen Wasserk\u00f6rper in der Tiefsee der Karibik hinweist.<\/p>\n

Das CTD-System wurde f\u00fcr den Einsatz aktiviert (Bild 1, CTD-R\u00f6hren ge\u00f6ffnet). Nachdem das CTD-System geborgen wurde (Bild 2, CTD-R\u00f6hren geschlossen), nahmen unsere Wissenschaftler Wasserproben aus verschiedenen Tiefen f\u00fcr diverse Zwecke (Bild 3). Beispielsweise wurden manche Wasserproben mit Eisenchlorid versetzt und gefiltert, um die Viruspartikel aus dem rotbraunen Niederschlag am Filter zu erhalten (Bild 4). Das gewonnene Material wird sp\u00e4ter durch Hochdurchsatz-Sequenzierung von DNA in K\u00f6ln analysiert, um die Virus-Diversit\u00e4t in der Tiefsee zu erforschen.<\/p>\n

Ihr M139-Team<\/p>\n

 <\/p>\n

\"\"

Image 1 | The CTD system on its way down to the deep sea. (Photo: Johannes Werner)<\/p><\/div>\n

\"\"

Image 2 | The CTD system on board again. The tubes were closed on the way up in selected depths. (Photo: Johannes Werner)<\/p><\/div>\n

\"\"

Image 3 | The scientists take the water samples out of the tubes and use them for different purposes. (Photo: Johannes Werner)<\/p><\/div>\n

\"\"

Image 4 | The enormous amounts of water samples of different depths are filtered that takes many hours. This time, red-brownish iron chloride is added to the samples in order to catch all virus particles. (Photo: Johannes Werner)<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

Dear interested reader, colleagues, friends and families, as mentioned in our last blog, we took water samples across 4000\u00a0m depth using the CTD (conductivity, temperature, depth) \u2013 rosette sampler at our first station in the Caribbean Sea. Here, we are interested in the distribution of viruses, bacteria and protists (unicellular organisms) in the depth. The […]<\/p>\n","protected":false},"author":183,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-132","post","type-post","status-publish","format-standard","hentry","category-deep-sea"],"_links":{"self":[{"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/posts\/132","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/users\/183"}],"replies":[{"embeddable":true,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/comments?post=132"}],"version-history":[{"count":5,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/posts\/132\/revisions"}],"predecessor-version":[{"id":141,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/posts\/132\/revisions\/141"}],"wp:attachment":[{"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/media?parent=132"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/categories?post=132"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.oceanblogs.org\/m139\/wp-json\/wp\/v2\/tags?post=132"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}