2006 Annual Science Report

Marine Biological Laboratory Reporting  |  JUL 2005 – JUN 2006

Executive Summary

Microorganisms were the only forms of life for more than three-fourths of Earth’s history. The effects of the microbial biosphere, driven by metabolism and expressed as biogeochemical processes, have imposed an overwhelming force on planetary change and have shaped Earth’s habitability. Microbial communities catalyze several significant chemical transformations within the biogeochemical cycles. Indeed, all macroscopic life completely depends upon processes mediated by complex microbial communities. Single-cell organisms are the most likely life forms to have either a history or a presence on other solar system objects. The Marine Biological Laboratory team investigates the diversity of microbial communities in sites that serve as analogues for past and present habitats on other solar system objects. We explore the evolution of microbial genomes, populations and communities in an effort to understand how biology shapes planetary processes. We investigate mechanisms such as those afforded by symbioses and phage infections ... Continue reading.

Field Sites
10 Institutions
7 Project Reports
0 Publications
0 Field Sites

Project Reports

  • Recognition of Theoretical Environments on Mars

    Our focus over the past year was a) to investigate the use of visible-near infrared spectroscopy of Rio Tinto to develop tools for recognizing habitable environments and b) investigating Mars data sets for habitable environment

  • Microbial Diversity and Population Structure Studies in the Rio Tinto

    We have begun analyzing data from a new molecular diversity survey method called SARST-V6 (Serial Analysis of Ribosomal Sequence Tags) applied to the October 2002 samples. With SARST, the PCR products from orthologous hypervariable regions (~100 bp long for the bacterial V6 region) in rRNA genes are ligated together to form large concatemers. Our SARST data are currently only available for bacteria. A total of 10,575 RSTs (ribosomal sequence tags) were BLASTED against the GenBank and RDP Databases

    ROADMAP OBJECTIVES: 3.3 5.1 5.2
  • Genome-Genome Integration: Symbiosis, Genetic Assimilation, and Evolutionary Innovation

    The broad goal of this project is to clarify genetic changes that mediate the establishment and diversification of genome-genome interactions. Using insect-associated endosymbionts as model systems, we are examining the molecular and evolutionary forces that shape associations between bacteria and eukaryotic hosts.

    ROADMAP OBJECTIVES: 4.2 5.1 5.2
  • Iron Oxidation – Shaping the Past and Present Environments
    ROADMAP OBJECTIVES: 4.1 5.1 6.1 7.2
  • Microbial Communities and Activities in the Deep Marine Subsurface

    Active archaeal communities. We are beginning to publish the results of our rRNA survey of selected deep subsurface sediments, focusing on active archaeal communities in the subsurface (Biddle et al. 2006, Sørensen and Teske 2006). All previous subsurface community analyses were based on DNA, which included the risk of detecting and analyzing remnant and fossil DNA from inactive or dead cells.

    ROADMAP OBJECTIVES: 5.1 5.3 6.1 6.2
  • The Evolution and Diversity of Ancient CO2-fixation Pathways in Anaerobic and Extremophilic Microorganisms: Clues to the Early Evolution of Life on Earth
    ROADMAP OBJECTIVES: 4.1 5.3 6.1 7.1
  • Microbial Diversity in the Deep Ocean

    The world’s oceans are teeming with microscopic life forms. The evolution of marine microbes over billions of years predicts the composition of microbial communities should be much greater than published estimates of a few thousand distinct kinds of microbes/liter of seawater. By adopting a massively parallel tag sequencing strategy, we explored bacterial communities of deep water masses of the North Atlantic (Figure 1) and diffuse flows associated with the hydrothermal vents of Axial Seamount (Figure 2)