Marine Ecosystems Research Department - jamstec japan agency ...

Japan Marine Science and Technology Center
Research Activities
Frontier Research System for Extremophiles
Object and Outline of Research and Development
Frontier Research System for Extremophiles conducts research on the organisms thriving in the deep-sea and
deep-subsurface from the viewpoint of extremophiles. We contribute to the progress of science and human welfare
by elucidating: ) what kinds of organisms are living in such extreme environments as the deep-sea and deep-subsurface,
) what are their distinctive features, and ) what is their usefulness in our daily life and/or industrial applications.
The scientific target is to elucidate the adaptation mechanisms of extremophiles toward such extreme environments
and to understand the origin of life through the discovery of the most ancient microorganisms. Another
target is to develop new biotechnologies through supplying new sources of useful microorganisms. Also, The Bio-
Venture Center for Extremophiles offers a forum for collaboration with researchers from industries that are interested
in exploiting the biological and chemical potential of extremophiles.
Isolation and cultivation of novel microorganisms from deep-sea sediments and deep-subsurface core samples are
continuously carried out. In addition, multicellular organisms in the deep-sea are captured and maintained by using the
DEEP AQUARIUM system. The tissue of deep-sea animals has been successfully cultured under laboratory conditions.
The whole genomic sequence of thermophilic Geobacillus kaustrophilus HTA- isolated from the Mariana
Trench has been mostly determined, and the comparative analysis of genomes in Bacillus species are conducted. On
the other hand, piezo-phisiology is aimed to elucidate microbial life under high pressure environments e.g., the identification
of genes responsible for high-pressure growth in yeast and the construction of transformants that respond to
high hydrostatic pressure in bacteria are carried out. Also, research on the behavior of biomaterials and colloidal dispersions
in supercritical water, one of extreme environments in deep-sea and deep-subsurface, is continuing.
The second Bio-Venture forum was held. Research collaboration is successfully proceeding with companies that
are interested in exploiting new biotechnologies.
Research Results
1. Microbial genome analysis
Aerobic endospore-forming Gram-positive Bacillus
species are distributed nearly ubiquitously in nature.
Recently some of these species have been reclassified
as members of species belonging to new genera such
as Alicyclobacillus, Amphibacillus, Brevibacillus,
Geobacillus, Halobacillus, Oceanobacillus, and
Salibacillus. These organisms have often been isolated
from various terrestrial soils and deep-sea sediments.
It is known that Bacillus-related species have a wide
range of environments for growth at pH -, with
temperatures around -˚C, salinity from to %-
NaCl, and pressures from . MPa (atmospheric pressure)
to at least MPa corresponding to the pressure
at a depth of m. Thus, these extremophilic
Bacillus-related species could possess adaptations to
multiple extreme environments including high and
low temperature, high and low pH, and high salinity.
Now we are very intrigued by the questions of how
these adaptive capabilities were acquired in their
genome and what the original genome structure was in
the ancestral progenitor Bacillus species.
We initiated the microbial genome sequencing project
in and have determined the complete genome
sequences of Bacillus halodurans and Oceanobacillus
iheyensis. An alkaliphilic Bacillus halodurans C-
isolated from terrestrial soil in is the most characterized
industrial strain, which produces various
kinds of useful enzymes. The B.halodurans C- is
the first industrial strain whose complete genome
sequence was determined. Oceanobacillus iheyensis
HTE isolated from the deep ocean near Nanseiisland
at a depth of m is an alkaliphilic and
extremely halotolerant bacterium. This strain was
selected as the second bacterium for the genome
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