Upper ocean biogeochemistry
Molecular microbial biology
Project Manager: Ed DeLong
Lead Scientist: Lynne Christianson, Peter Girguis
Lead Engineer: Farley Shane, Ed Mellinger
Microbes critically impact and mediate nearly every major biogeochemical
cycle on Earth. Microbial interactions that occur on the scale of microns can
regulate global ocean processes on planetary wide scales. Although general
procedures to detect, identify and functionally characterize and quantify
microbial species and their activities in the marine environment are improving,
they are still relatively crude, and lack resolution and sensitivity.
project will continue the development and refinement of new approaches to
qualitatively and quantitatively describe microbial species and their activities
in the marine environment. We will extend the development and implementation of
novel genome-enabled technologies, to better characterize microbially mediated
biogeochemical processes. New methodologies will be coupled to MBARI-developed
platforms and systems for sampling and measurement throughout the water column,
and in the benthos. Specific focal areas include determining the relative
significance of newly discovered marine phototrophs, which use either rhodopsin-based
or bacteriochlorophyll-based photosystems. In addition, we plan to better
characterize the poorly understood planktonic archaea, that comprise 20% of all
the microbial cells in the ocean, and have recently been implicated in CO2
fixation in the deep sea. In the benthos, we will further characterize those
microbes responsible for anaerobic methane oxidation, a microbial process that
cycles large amounts of methane in anaerobic marine sediments, and fuels
chemosynthetic communities at methane seeps. We plan also to begin, with MBARI
and other colleagues, the study of microbial species and processes at
hydrothermal vents. Our general developmental areas of focus for this project
- Conversion of the PISUS (Picoplankton in situ Ultrafiltration System) pump
motor from the ROV Ventana's hydraulic power to an electric power source.
- Refinement of high sensitivity techniques to quantify and map marine
microbial species in space and time.
- Development of novel activity assays using genome sequences recovered from
Monterey Bay microbes.
- Development of new approaches for constructing gene expression libraries,
to identify and characterize important biogeochemical processes as they
occur in the water column.
- Development of benchtop and in situ incubation systems to characterize
microbial communities and activities at methane seeps and hydrothermal