Update from Andreas Teske’s Research/Study Leave – March
My research leave at the Hanse Institute for Advanced Studies in Northern Germany is strengthening the long-standing collaborative ties of my lab to our colleagues working in marine microbiology and geochemistry at the Universities of Bremen and Oldenburg. The windswept coastal plains of Holland, northern Germany and Denmark attract marine scientists and especially microbiologists; the stormy North Sea is fringed by excellent research centers and institutes in these fields, and my years of graduate research at one of them – the Max-Planck-Institute for Marine Microbiology in Bremen – have obviously left a mark. Cultivating old and new connections opens up ever-changing research perspectives and new projects, and the Hanse Institute (pictured below) does its part by providing a well-equipped base with living quarters, library, espresso machine and a conference center.
Many of my projects focus on the microbial response to man-made and natural hydrocarbon contamination, and I start with the largest oil-and gas blowout in recent times, the Deepwater Horizon spill. My recent graduate Tingting Yang had found gene-based evidence of novel oil-degrading bacteria – members of a widespread marine group called the Roseobacter cluster – that are especially active in highly-weathered oil residues floating on the sea surface in the aftermath of the Deepwater Horizon oil spill. Yet these bacteria did not appear in the wide spectrum of cultured isolates in any of the laboratories working on Deepwater Horizon microbiology; they posed an obvious challenge to domestication in the lab and could therefore not be studied for their biochemical properties and oil-degrading activities. With our best (or more precisely, most oil-contaminated) sea surface oil samples in hand, the Roseobacter experts at Oldenburg University, the team led by Profs. Brinkhoff and Simon, managed cultivating these elusive but highly active bacteria, and identified their biochemical specialty (cracking complex aromatic compounds) that allowed them to thrive in the hydrocarbon-polluted Gulf of Mexico; shown in the photo on the right is the orange-brown weathered oil (in May 2010) from where these aromatics degraders were isolated. The genome of these bacteria – a new genus – is now sequenced and provides, together with detailed physiological studies of this organism, a new blueprint for the natural microbial oil spill response in the ocean. This Roseobacter survey will be extended by sharing new, well-characterized sample sets of marine sediment from other locations with our collaborators from Oldenburg University.
Not all hydrocarbon-degrading marine bacteria respond to man-made disasters; some thrive in natural oil seeps and constitute natural marker populations for methane, alkane, and aromatics-rich marine sediments. The hydrothermally active oil seeps of Guaymas Basin, an active seafloor-spreading center at 2000 m depth in the Gulf of California, provide an especially active model system for these organisms; samples of Guaymas Basin sediments have to be obtained by submersible, HOV Alvin (pictured on photo), and its mother ship, RV Atlantis. The entire Teske lab, especially the undergraduates, collaborated on a detailed study on bacterial populations in an alkane-rich hydrothermal sediment site in Guaymas Basin (Dowell et al. 2016; doi: 10.3389/fmicb.2016. 00017). Together with my long-term collaborator Kai-Uwe Hinrichs at the Center for Marine Environmental Sciences of Bremen University, we are now extending this study to the entire alkane dataset from Guaymas Basin and look for patterns in the data that indicate microbial alkane processing. Together with experts on microbial habitat studies from the Max-Planck-Institute for Marine Microbiology, additional Guaymas Basin projects are in preparation; these collaborations will ensure that we make the most of the next NSF-funded visit to Guaymas Basin, scheduled for December 2016. My entire lab will participate in this cruise (which I am heading as chief scientist), and work with our Max-Planck collaborators onboard of RV Atlantis.
In addition to collaborative projects, I got drafted into PhD thesis committees in Oldenburg (nearby) and in Aarhus (5 hours away in Denmark), and into giving seminar talks in approximately equal frequency on the Deepwater Horizon oil spill and on Guaymas Basin. On this side of the great pond, there is a lot of interest in these topics, and for good reason; the North Sea is crisscrossed by shipping lanes (including oil tankers, of course) and dotted all over with oil and gas drilling wells. In this regard, the Gulf of Mexico and Guaymas Basin are not exotic, distant places, but examples and model systems for environmental problems that Europe is facing just the same.
More in my next update!