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Dr. Kevin W. Becker

Archived Page

This web page has not been updated since the former colleague left MARUM.

Research interests

Organic geochemistry
Biomarker research
Paleoenvironmental research
Microbial ecology
Development of analytical methods

Member of the Organic Geochemistry group/Hinrichs Lab

Curriculum vitae

13 August 2015	PhD defense at the Department of Geosciences, University of Bremen Title: Respiratory quinones and intact membrane lipids as tracers for microbial community composition and redox conditions in the ocean and sediments
November 2011 - August 2015	PhD student in the Organic Geochemistry Group at MARUM - Center for Marine Environmental Sciences, University of Bremen, Germany Thesis title: Biogeochemical significance and biomarker potential of novel glycerolipids and respiratory quinones in the marine environment
April 2011 - October 2011	M.Sc. thesis at MARUM - Center for Marine Environmental Sciences, University of Bremen Thesis title: Improved chromatographic separation of archaeal Glycerol Dialkyl Glycerol Tetraethers and its application to sediments from the Mediterranean and Black Seas
October 2009 - October 2011	Master of Science Geosciences, Depatement of Geosciences, University of Bremen, Germany
July 2009 - September 2009	B.Sc. thesis at MARUM - Center for Marine Environmental Sciences, University of Bremen Thesis title: "Untersuchung von Lipid Biomarkern an Sedimentproben des Multicores GeoB 10709-4 am Schelf Süditaliens (Golf von Tarent)"
October 2007 - September 2009	Bachelor of Science Geosciences, Depatement of Geosciences, University of Bremen, Germany

PhD project

Biogeochemical significance and biomarker potential of novel glycerolipids and respiratory quinones in the marine environment

Project page: DARCLIFE

Microorganisms drive globally important biogeochemical cycles and they have shaped the elemental composition of Earth’s surface environments and interior. Within the marine carbon cycle, they are involved in both, a large fraction of primary production and turnover of organic carbon through mineralization processes. Thus, the oxygen we breathe is to a large extent produced by microbes, but they also play an important role for the regulation of greenhouse gases, such as carbon dioxide and methane, and are consequently involved in processes that drive climate at geological time scales. Microbial life on Earth has further adapted to a wide range of environments including some of the most hostile imaginable, exhibiting for example extreme pressures, temperatures, acidity and alkalinity, and limited energy and nutrient availability. However, we only have fragmentary understanding of the abundance, diversity and function of microbial life especially in hardly accessible system, such as deep marine sediments.
My research project was connected with the interdisciplinary project ‘Deep subsurface Archaea: carbon cycle, life strategies, and role in sedimentary ecosystems’ (DARCLIFE). It was guided by the overarching DARCLIFE objectives to constrain the environmental factors that control the distribution, abundance, and composition of archaeal communities in marine sediments and to examine the fundamental properties of life at minimum energy conditions. As my research approach relies on the analysis of membrane lipids as indicators for live cells, my specific aims were: (i) to improve analytical methods for the detection of archaeal and bacterial membrane lipids, (ii) to identify novel lipids in subsurface sediments, and (iii) to investigate the source and proxy potentials of the novel lipids. Water column and sediment samples for my project have been collected during RV Meteor cruise M84/1 (DARCSEAS) from the eastern Mediterranean, Sea of Marmara and southern Black Sea, providing an ideal set of environmentally diverse settings in close proximity. These settings include anoxic to oxic and slightly brackish to saline and even hypersaline geochemical regimes, marine and terrestrial sediment sources, organic-rich and organic-lean sediments, as well as eutrophic and oligotrophic environments.

The thesis can be downloaded here.

Schematic diagram illustrating the major oceanic microbial habitats including the water body and diferent environments in the subseafoor as well as the major biogeochemicalprocesses the microbes are mediating in each habitat. Additionally, the major fuxes of the marine carbon cycle are shown. Figure from Becker (2015, PhD thesis).

Publications

[9] Elvert, M., Pohlman, J.W., Becker, K.W., Gaglioti, B., Hinrichs, K.-U. and Wooller, M.J. (in press). Methane turnover and environmental change from Holocene lipid biomarker records in a thermokarst lake in Arctic Alaska. The Holocene. doi: 10.1177/0959683616645942

[8] Hamann, E., Gruber-Vodicka, H., Kleiner, M., Tegetmeyer, H.E., Riedel, D., Littmann, S., Chen, J., Milucka, J., Viehweger, B., Becker, K.W., Dong, X., Stairs, C.W., Hinrichs, K.-U., Brown, M.W., Roger, A.J. and Strous, M. (in press). Environmental Breviatea harbour mutualistic Arcobacter epibionts. Nature, Advanced Online Publication. doi: 10.1038/nature18297

[7] Becker, K.W., Elling, F.J., Yoshinaga, M.Y., Söllinger, A., Urich, T., Hinrichs, K.-U. (in press). Unusual butane- and pentanetriol-based tetraether lipids in Methanomassiliicoccus luminyensis, a representative of the seventh order of methanogens. Applied and Environmental Microbiology. doi: 10.1128/AEM.00772-16

[6] Elling, F.J.*, Becker, K.W.*, Könneke, M., Schröder, J.M., Kellermann, M.Y., Thomm, M., Hinrichs, K.-U. (2016). Respiratory quinones in Archaea: phylogenetic distribution and application as biomarkers in the marine environment. Environmental Microbiology 18(2), 692-707. *These authors contributed equally to this work. doi: 10.1111/1462-2920.13086

[5] Becker, K.W., Lipp, J.S., Wörmer, L., Versteegh, G.J.M., Hinrichs, K.-U. (2015). Rapid and simultaneous analysis of three molecular sea surface temperature proxies and application to sediments of the Sea of Marmara. Organic Geochemistry 85, 42-43. doi: 10.1016/j.orggeochem.2015.04.008

[4] Elling, F.J., Könneke, M., Lipp, J.S., Becker, K.W., Gagen, E.J., Hinrichs, K.-U. (2014). Effects of growth phase on the membrane lipid composition of the thaumarchaeon Nitrosopumilus maritimus and their implications for archaeal lipid distributions in the marine environment. Geochemica et Cosmochemica Acta 141, 579-597 doi: 10.1016/j.gca.2014.07.005

[3] Zhu, C., Lipp, J.S., Wörmer, L., Becker, K.W., Schröder, J., Hinrichs, K.-U. (2013). Comprehensive glycerol ether lipid fingerprints through a novel reversed phase liquid chromatography-mass spectrometry protocol. Organic Geochemistry 65, 53-62. doi: 10.1016/j.orggeochem.2013.09.012

[2] Becker, K.W., Lipp, J.S., Zhu, C., Liu, X. and Hinrichs, K.-U. (2013). An improved method for the analysis of archaeal and bacterial ether core lipids. Organic Geochemistry 61, 34-44. doi: 10.1016/j.orggeochem.2013.05.007

[1] Wooller, M.J., Pohlman, J.W., Gaglioti, B.V., Langdon, P., Jones, M., Walter Anthony, K.M., Becker, K.W., Hinrichs, K.-U., Elvert, M. (2012). Reconstruction of past methane availability in an Arctic Alaska wetland indicates climate influenced methane release during the past ~12,000 years. Journal of Paleolimnology 48, 27-42 (Arctic Lakes Special Issue). doi: 10.1007/s10933-012-9591-8

Oral presentations

Becker, K.W., Elling, F.J. , Schröder, J.M., Könneke, M., Kellermann, M.Y., Thomm, M., Hinrichs,K.-U. Respiratory quinones in archaeal cultures and the environment: evolutionary implications, biomarker potential and geochemical significance. 27th International Meeting on Organic Geochemistry. Prague, Czech Republic, 2015.

Lipp, J.S., Becker, K.W., Zhu, C., Hinrichs, K.-U. Separation of archaeal tetraether lipids: state-of-the-art and future perspectives. GDGT 2014, Texel, NL, 2014.

Hinrichs, K.-U., Becker, K.W., Elling, F.J., Lipp, J.S., Liu, X., Meador, T.B., Schröder, J., Yoshinaga, M., Zhu, C. Distribution patterns of recently identified GDGTs and their polar derivatives in the environment. GDGT 2014, Texel, NL, 2014.

Becker, K.W., Lipp, J.S., Versteegh, G.J.M., Wörmer, L., Hinrichs, K.-U. Advanced analytical methodology for analysis of sea surface temperature proxy relevant biomarkers. 7th Bremen PhD days in Marine Sciences, Etelsen, Germany, 2014.

Becker, K.W., Lipp, J.S., Gal, J.-K., Heuer, V.B., Elvert, M., Hinrichs, K.‐U. Microbial life in a deep‐sea hypersaline anoxic basin. 6th Bremen PhD days in Marine Sciences, Etelsen, Germany, 2013.

Becker, K.W., Lipp, J.S., Zhu, C., Liu, X. and Hinrichs, K.-U. An improved analytical method for the analysis of archaeal and bacterial ether lipids. Gordon Research Seminar on Organic Geochemistry, Holderness, NH, USA, 2012.

Poster presentations

Goldenstein N.I., Becker, K.W., Könneke, M., Liu, X.-L., Heuer, V.B. and Hinrichs, K.-U. Particle size fraction controls production and export of intact polar and core lipids in the Western Mediterranean Sea. Gordon Research Conference on Organic Geochemistry, Holderness, NH, USA, 2014.

Becker, K.W., Lipp, J.S., Versteegh, G.J.M., Wörmer L., Vogel, C. and Hinrichs, K.-U. A streamlined protocol for the determination of three molecular SST proxies in a single analysis. Gordon Research Conference on Organic Geochemistry, Holderness, NH, USA, 2014.

Becker, K.W., Lipp, J.S., Heuer, V.B., Elvert, M. and Hinrichs, K.-U. Microbial Lipids in the deep-sea hypersaline anoxic Discovery Basin, Eastern Mediterranean Sea. GDGT 2014, Texel, NL, 2014

Becker, K.W., Lipp, J.S., Lazar, C.S., Heuer, V.B., Elvert, M., Gal, J.-K. and Hinrichs, K.-U. Microbial lipids in the deep-sea hypersaline anoxic Discovery Basin, Eastern Mediterranean. 26th International Meeting on Organic Geochemistry. Costa Adeje, Tenerife, Spain, 2013.

Gal, J.-K., Badejo, A., Lee, D.-H., Nam, S.-I., Yoon, H.I., Becker, K.W., Liu, X.-L., Hinrichs, K.-U. and Shin, K.-H. Interpretation of GDGTs in Arctic and Antarctic sediment. 26th International Meeting on Organic Geochemistry. Costa Adeje, Tenerife, Spain, 2013.

Becker, K.W., Lipp, J.S., Zhu, C., Liu, X., Hinrichs, K.-U. An improved analytical method for the analysis of archaeal and bacterial ether lipids. Gordon Research Conference on Organic Geochemistry, Holderness, NH, USA, 2012.

Zhu, C., Lipp, J.S., Wörmer, L., Becker., K.W., Schröder, J.M. and Hinrichs, K.-U. Reverse Phase Liquid Chromatography-Mass Spectrometry Methodology for Analysis of Intact and Core Ether Lipids. Gordon Research Conference on Organic Geochemistry, Holderness, NH, USA, 2012.

Elvert, M., Wooler, M.J., Becker, K.W., Gaglioti, B., Hinrichs, K.-U., Pohlman, J.W. Carbon hydrogen isotope biomarker records of methane release and hydroclimatic variability from a thermokarst lake in arctic Alaska. 25th International Meeting on Organic Geochemistry. Interlaken, Switzerland, 2011.

Expeditions

February 2011	RV Meteor cruise M84/1 "DARCSEAS - Deep subseafloor Archaea in the eastern Mediterranean, Marmara and Black seas: carbon cycle, life strategies, and role in sedimentary ecosystems"
April 2010	Alaska North Slope - "Source characterization and temporal variation of methane seepage from thermokarst lakes on the Alaska North Slope in response to arctic climate change"