Ramunas Stepanauskas


Senior Research Scientist

Director SCGC

Bigelow Laboratory for Ocean Sciences 
60 Bigelow Drive
PO Box 380
East Boothbay, Maine 04544
Phone: +1 207-315-2567, ext. 308
Fax: +1 207-315-2329


  • Ph.D., Ecology, Lund University, Sweden, 2000
  • M.A.,  Limnology, Lund University, Sweden, 1995
  • B.A.,  Limnology, Uppsala University, Sweden, 1993

Research Interests 

3-min video update on my research activities (October 16, 2014)

Stepanauskas’ research group studies biogeochemical roles, trophic interactions, evolutionary histories and biotechnological potential of microorganisms inhabiting oceans, deep subsurface, and other environments. Unicellular, microscopic bacteria, archaea and eukaryotes constitute the oldest, the most abundant, and the most diverse forms of life on our planet. Remarkably, this fundamental insight is fairly new to science, and was enabled by technological advances in culture-independent, molecular research tools. However, microbial diversity remains severely underexplored and poorly defined, due to its sheer vastness, fundamental biology differences from the better-studied multicellular organisms, technical limitations of commonly used techniques, and paucity of unifying concepts that are based on adequate field data. For example, many microbial ecology studies rely on surveys of the SSU rRNA genes, although biological features and evolutionary histories of most microorganisms carrying these genes remain completely unknown. To overcome these challenges, my colleagues and I developed robust methods and high-throughput infrastructure for microbial single cell genomics, which uncovers hereditary information at the most basic level of biological organization and provides genomic blueprints of the vast “microbial dark matter”. This novel technology, in combination with other research tools, is transforming a broad spectrum of microbial study areas. Active research projects include:

  • Untangling the Deep Genealogy of Microbial Dark Matter (NSF)
  • Ocean's dark energy: Global inventory of chemoautotrophs in the aphotic realm (NSF)
  • An Integrated Study of Energy Metabolism, Carbon Fixation, and Colonization Mechanisms in Chemosynthetic Microbial Communities at Deep-Sea Vents (NSF)
  • From genome to mechanism: understanding microbial iron metabolism in situ (NASA)