 The research vessel Persei brings Lab researcher
Tamas Torok and his Russian colleagues to the shore of Lake Baikal to collect microbes
from a nearby hot spring
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"Only five years ago Vector had 3,500 scientists," says Tamas Torok of the
Life Sciences Division. "Now they are down to 1,500. Luckily these are top staff,
people you wouldn't want to see working for any third party."
Torok recently returned from a visit to Vector and to the Lake Baikal region, where, in
collaboration with Vector microbiologist and institute director V.E. Repin he began a
search for ancient and as yet unknown microorganisms with novel medical and
biotechnological potential.
Torok is a member of Berkeley Lab's Center for Environmental Biotechnology (CEB),
headed by Jennie Hunter-Cevera of the Earth Sciences and Life Sciences Divisions.
Hunter-Cevera is the principal investigator of both the Lake Baikal project and another
IPP project to screen rare botanical and microbial extracts, undertaken with the
International Institute of Cell Biology and the Institute of Microbiology and Virology,
both in Kiev, Ukraine.
With industrial partners from the American Home Products Corporation's Wyeth-Ayerst
Research Laboratories and Cyanamid Agricultural Research Center, Hunter-Cevera and her
colleagues are searching for biological products with market potential, making use of
thousands of plant species already collected throughout the former Soviet Union, plus
novel microbes from various sites, including Chernobyl.
"Radiation exposure over time has most likely altered the ways microorganisms in
the soils near the Chernobyl reactor metabolize and respond to stress," says
Hunter-Cevera. "We want to screen extracts with high-throughput methods, including
robotic methods invented here at the Lab, to see if we can isolate new classes of
antibiotics or new drugs active against cancer. If so, some good will have come from this
tragedy."
Earlier this year Hunter-Cevera and her Ukrainian colleagues were working within 100
meters of the concrete "sarcophagus" that encases the reactor and its melted
core. "We were allowed to work in the vicinity just eight hours," she says,
"and then at four o'clock in the afternoon we'd go off to have lunch. All the food
had to be brought in from outside the area. They topped it off with a special brand of
vodka guaranteed to cure radiation damage." She laughs and jokes, "Maybe it has
a chelator to pull out the actinides. Whatever it does for radiation damage, it gave me
the worst hangover since college."
In the wild taiga of the Buryat Republic, south of Lake Baikal, Tamas Torok encountered
a different use for vodka. The Buryats came into the region from Mongolia at the time of
Genghis Khan; to insure successful journeys, professional success, and good luck in
general, they make frequent offerings of cigarettes, small coins, and splashes of water --
or vodka -- to a being known as Burhan, "the great ghost."
The journey
Torok began his Siberian journey at Irkutsk, then made his way to Ulan Ude and beyond,
traveling by vintage plane -- which makes the circuit from Samara to Novosibirsk to
Irkutsk just twice a week -- then by train, and finally by off-road van, ten hours over
nonexistent roads through the snow and mud of mountains and forests, to the "Saint's
Nose" peninsula on Lake Baikal's southeastern shore, dragging his entire laboratory
with him in two ice chests.
"The only time I lost my temper was when the conductor wouldn't let me on the
train with my chests," Torok recalls. "My Russian colleagues couldn't persuade
her, but English somehow did the trick." The ice chests nearly filled his upper bunk,
and Torok was reconciled to spending the 10-hour overnight ride clinging to a strip of
bedding a few inches wide, until a Buryat man insisted on moving one of the chests into
his own bunk.
The lake and the samples
Torok went to Lake Baikal because it is an isolated environment with extraordinarily
diverse aquatic life -- some 1,500 species, 85 percent of which have turned out to be
unique (including a fresh-water seal!). The likelihood that one could find unusual
microorganisms was therefore high; it was also possible that these microbes might be
"ancient" -- that is, that they had evolved relatively slowly compared to
microorganisms elsewhere.
Lake Baikal is not only the biggest lake in the world, with 20 percent of the Earth's
fresh surface water -- more water than all the Great Lakes combined; it is also the
world's oldest, over 30 million and perhaps as much as 45 million years old. The lake
floor averages a mile down, but that floor consists of sediments which fill a rift in the
Earth's crust more than five miles deep.
From rented research vessels Torok took samples of deep lake water, seeking unknown
organisms adapted to the cold. From hot springs in the surrounding region he took samples
which may contain unknown organisms with heat adaptations. Enzymes responsible for
resistance to temperature and other extremes, such as acidity, have great potential in
manufacturing processes.
A third source of unique specimens came as an unexpected bonus.
"For several years the International Baikal Drilling Project, a consortium of
U.S., Japanese, European Community, and Russian scientists, has been taking core samples
from sediments in different parts of the lake," Torok explains. "Layers of
sediment can be dated almost like tree rings, and by looking at remains of aquatic life
and other deposits, they get an indication of how the climate has changed over millions of
years."
Core drilling can only be done for a few weeks in winter. After the ice is frozen over,
an ice breaker tows the drilling barge to the chosen site; the researchers wait until the
ice-breaker's trail is refrozen before they can begin drilling into the sediments a mile
beneath the ice, bringing up cores from as deep as a 1,000 meters below the lake bed.
"The core samples are divided up between the local and international scientists --
all kinds of scientists, except microbiologists," says Torok. "When we met, both
parties saw an incredible opportunity. They gave up some of their cores; I've got 47
samples from the 1998 drilling to work on right here at the Lab." Torok says that
coring is just too expensive for microbiologists like himself to have considered,
"but once it's done, you just pick up the core samples." He's hoping to find
sponsorship so that he can sample the project's final season of drilling, which will begin
this January.
Torok returned from Siberia with the soil and water samples he went for, plus the
unexpected bonus of the ancient lake sediments. CEB's lab is chock full of microorganic
treasures awaiting analysis.
A scientific success, the trip also left Torok deeply impressed with the Siberians.
"Most of the people are so poor they have no reason for dishonesty," he says.
"If someone catches a fish, they divide it up right there. In a cabin without running
water or beds, they made me sleep on the table; it was a place of honor. They share
everything they have. They are so human. And so helpful."
