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First
Annual Astrobiology Science Conference...03/23/00
NASA
NASA will host an international conference on astrobiology science to be held
this spring at NASA Ames Research Center, Mountain View, California, on April
3-5, 2000. The focus of the meeting is on scientific results that illustrate
the broad multidisciplionary nature of astrobiology. As such, this conference
will complement other, more narrowly focused meetings that
deal primarily with one or two subdisciplines of astrobiology. We hope that
this conference will become an annual event and will help to develop a growing
constituency for astrobiology within the international scientific community.
What is Astrobiology?
Astrobiology is the study of the origin, evolution, distribution, and destiny
of life in the universe. It uses multiple scientific disciplines and space technologies
to address fundamental questions:
How does life begin and develop?
Does life exist elsewhere in the universe?
What is life's future on Earth and beyond?
These questions are age-old. But now, for the first time in human history, advances in the biological sciences, space exploration and space technology make it possible for us to answer them.
Full Story: http://astrobiology.arc.nasa.gov/conferences/2000/ABSciConf/
Mitch Battros
Producer - Earth Changes TV
http://www.earthchangesmedia.com
Scientists
Report On The Sequenced Fly Genome...03/23/00
By Lori Stiles, University Of Arizona News
A team of almost 200 scientists reports tomorrow in Science how they have essentially
completed sequencing the whole
genome of the Drosophila fruit fly.
The feat lays the foundation for a new era in genetics research, they report.
Scientists will no longer have to spend time
searching for genes. They will be asking what the genes do.
And it demonstrates that the controversial whole-genome "shotgun"
sequencing technique can be used successfully to
sequence larger genomes including the human genome, they add.
The team of authors comprises scientists from Celera Genomics Corp. of Rockwell,
Md., the Berkeley and European
Drosophila Research Projects, and a few dozen scientists from around the world
who are experts in various areas of fly
research, including the University of Arizona's Boris Dunkov.
Gene Myers, Vice President for Informatics Research at Celera and an author
on the Science paper, is a UA professor of
computer science on leave from the university. (See the Jan. 13, 1999 news release,
"UA computer scientist joins venture to
'shotgun' sequence human genome." The story is online at the UA News Services
science and research website, <
http://science.opi.arizona.edu >)
A genome is all of the genetic material, or hereditary information, in an organism.
Geneticists have studied fruit flies for nearly
a century. Twenty years ago, scientists begun using recombinant DNA cloning
and sequencing techniques to identify particular
genes and map their location in the fly genome. The federally funded Human Genome
Project in 1990 selected Drosophila as
a model organism for study, giving rise to several genome projects in the U.S.,
Europe and Canada.
The Berkeley Drosophila Genome Project group had sequenced about a fifth of
the fruit fly genome using recombinant DNA
cloning methods when, in January 1999, it joined with Celera in the effort to
sequence the entire fly genome.
Celera is pioneering the whole-genome shotgun sequencing strategy. This technique
randomly breaks apart all the DNA of an
organism, sequences the fragments, then reassembles the pieces in overlapping
sequences to reconstruct the complete
genome sequence. The method bypasses the time-consuming gene-mapping step in
the traditional gene sequencing method.
Berkeley collaborators supplied the extensive clone-based sequence and other
supporting data in their joint fly genome
project with Celera. In September 1999, Celera and Berkeley scientists announced
they had sequenced the fly genome that
encodes some 13,600 genes in 1.8 billion base pairs of DNA.
In November, a month before releasing all the sequence data in GenBank, Celera
and the Berkeley group invited 40 scientists
from the international fly research community to take a first look at the sequenced
Drosophila genome.
Boris Dunkov was among those invited to Celera for the 2-week "Annotation Jamboree."
"When I got a first look at the sequenced fly genome, it was amazing,"
Dunkov said. "I was overwhelmed with the amount of
information that, suddenly, was there."
Dunkov is an insect biochemist who has worked with Drosophila in studying iron
metabolism and cytochrome P450 enzymes,
a large family of enzymes that play a major role in the insect's life. These
enzymes are important in the synthesis and/or
degradation of hormones and pheromones, and in the metabolism of natural and
synthetic toxicants, including insecticides.
The jamboree was a first-cut exercise for Drosophila experts to work on the
initial "annotation" of the assembled fly genome,
Dunkov said.
The scientists were asked to organize and interpret the gene set for a given
protein family or biological process -- in Dunkov's
case, the fly's cytochrome P450 enzymes and iron-binding proteins. They worked
to define genes, to classify them according
to predicted function, and to understand how it all fit in the whole-genome
picture.
Even with computer gene-finding tools and the efforts of the large community
of Drosophila researchers, annotating the entire
fly genome "will take years," Dunkov noted. To annotate the entire
genome involves discovering all the proteins which are
encoded by the genome and learning how proteins function as the fly develops
and lives its life.
"But the availability of the annotated fruit fly genome sequence will
change the way we do research in biochemistry and
physiology of other insects -- economically and medically important insects,"
Dunkov said.
Drosophila is the champion biological model for studying agriculturally important
insect pests and insects which, as vectors of
diseases like malaria and dengue fever, kill millions of people annually. Dunkov
also works with mosquitoes as vectors of
disease. He predicts a boom in new insect genome projects focused on insects
of agricultural and medical importance.
The fruit fly is one of the best studied and genetically understood of all
organisms, notes Regents Professor Margaret G.
Kidwell of the University of Arizona. She is an evolutionary geneticist who
has been studying mobile genetic elements, or
"transposons," for more than 25 years, specializing in those found
in Drosophila fruit flies. (See the Feb. 21, 2000, news
release "Mobile Elements, Evolution and Human Disease." The story
is online at the UA News Services science and research
website, <http://science.opi.arizona.edu
>)
"I think this is a pretty important achievement," Kidwell said. "The
shotgun approach has been remarkably successful, despite
many earlier doubts. And looking ahead, it promises well for the on-going human
genome sequencing effort.
"The sequencing of the Drosophila genome represents the successful completion
of one more important step in place to first
sequence the relatively small genomes of important experimental organisms
bacteria, yeast, flies and worms before
attacking the considerably larger human genome," Kidwell said. "The
smaller genomes are biologically interesting in their own
right as well as serving as pilot projects to refine the tools for automated
sequencing and computational analysis of the human
genome."
In the past few years, human geneticists have realized just how important the
Drosophila genome is for understanding the
human genome and human disease. They have discovered striking "homologies,"
or sequence similarities, between fly and
human genes. They have discovered that whole pathways of developmental and cellular
processes in flies are maintained in
humans, using the same molecules.
Celera is using the shotgun strategy to sequence the 3.5 billion base pairs
in the human genome, a project that will be finished
by the end of the year, according to senior company executives.
Unfortunately, a public/private arrangement that worked well in sequencing
the Drosophila genome may not work in
sequencing the human genome. At this point, public and private human genome
project directors are contesting who will
control the raw data.
Boris Dunkov, University of Arizona, 520-6213046, dunkov@u.arizona.edu
Gene Myers, Celera Genomics Corp., 240-453-3007, Gene.Myers@celera.com
Mitch Battros
Producer - Earth Changes TV
http://www.earthchangesmedia.com
Pfiesteria,
The Cell From Hell...03/23/00
By Geoff Burchfield
In February of this year, an international team ofbiologists met in Hobart,
Tasmania to discuss what they believe is a global crisis the sudden appearance
of strange marine micro-organisms capable of poisoning not just fish but people
too. One researcher from North Carolina in the US told the conference shed
discovered an aggressive new species.
It wasnt the first time that JoAnn Burkholder had made such a claim. But back in 1992, when shed tried to raise the alarm about a bizarre kind of alga, shed been ridiculed. Three years later, that organism, known as Pfiesteria, re-surfaced to foul water, devestate American fisheries and cause one of the biggest health scares in recent US history.
This strange creature is now the focus of a divisive multi-million dollar research
race thats become increasingly bogged down in politics, big business,
and academic rivalry. Along the way JoAnn has had to face death threats and
her research partner has
been almost killed by Pfiesteria itself. Its a story with major implications
for the rest of the world, including Australia where similar organisms have
recently been discovered in coastal waters.
Full Story: http://www.abc.net.au/quantum/stories/s112832.htm
Mitch Battros
Producer - Earth Changes TV
http://www.earthchangesmedia.com
Cyanide Leaks
Into Papua New Guinea River System...03/23/00
Nando Media
PORT MORESBY, Papua New Guinea - A large quantity of deadly cyanide has likely
contaminated a jungle water system in Papua New Guinea, prompting authorities
to warn villagers against drinking the water.
A one-ton box of the chemical accidentally dropped from a helicopter on Tuesday
about 55 miles north of the
capital, Port Moresby, and mining officials said some of it probably escaped
into the surrounded water system.
Dome Resources NL said it sent cleanup teams sent to the site, and expected
to recover most of the material.
But as much as 330 pounds had probably washed into nearby streams, managing
director Michael Silver told
Sky News television in Sydney, Australia.
He said he couldn't guarantee that the cyanide didn't pose a threat to anyone
drinking the water. Even small
quantities of cyanide can be lethal.
Papua New Guinea's National Disaster and Emergency Service issued a warning
for people not to drink from
rivers and streams in the area.
Environmental groups worried that villagers in the remote area may not get the warning.
Silver said Dome would monitor all waterways in the region for cyanide contamination,
adding that the dissolved
cyanide "would be diluted very substantially and fortunately the area in
which it has landed is very sparsely
populated."
The cyanide was destined for the Australian-owned Tolukuma gold mine, which
uses the chemical to extract
gold in the mining process.
Scientists Investigate Whales' Deaths...03/22/00
By Jessica Robertson - Nando Media
FREEPORT, Bahamas - Eight whales beached and died soon after the U.S. Navy conducted
anti-submarine exercises off the northern Bahamas. The deaths prompted an investigation
and calls for an end to the exercises.
The Navy said Tuesday that there was no evidence to link the whale deaths to
last week's exercise testing sonar
detection of submarines.
Navy Cmdr. Greg Smith said the tests took place from about 1 p.m. to 5 p.m.
March 15 off Abaco Island - part of
a series of exercises testing "sonar buoys" that were to continue
through March 22.
Marine biologist Ken Balcomb of the Earthwatch environmental group said beachings
began that same day,
and within two days at least 14 whales had grounded themselves on Abaco, Grand
Bahama to the north, and
Eleuthera to the south. Eight died, prompting investigations by Bahamian and
U.S. scientists and authorities.
"A whale beaching in the Bahamas is a once-in-a-decade occurrence,"
said Balcomb, an American who has
been studying whales around Abaco island for nine years.
"We will be making recommendations to the Bahamian government that these
sort of exercises be terminated,"
he said. "The fact that it coincides with the military exercises cannot
be just coincidental."
But the Navy spokesman said there was no evidence linking the two events. "My
understanding of the actual
locations would put the island between the operations where the `sonobuoys'
were located and where the
whales eventually beached themselves," said Smith.
Naomi Rose of the Washington-based Humane Society of the United States, maintained
the signals could still
do damage.
"These signals, depending on frequency, could travel quite a distance
and could even wrap around the island,"
said Rose, a marine mammal scientist. "One could argue that they fled the
area where the sonar was being
transmitted."
Another U.S. marine biologist here to investigate, Charles Potter of the Smithsonian
Institute, said the number of
whales beached is "extremely unusual. But he said the postmortems showed
the whales had suffered no
physical damage, such as broken ear drums.
Balcomb said the mammals included several deep-water beaked whales, goose beaked
whales measuring
16-19 feet, dense beaked whales measuring 10-13 feet, baleen whales measuring
up to 27 feet and some
small minke whales.
Michael Breynan, director of the Bahamian Fisheries Department, said he was
working with U.S. scientists to
try to determine the cause. Breynan said his department kept no records of beached
whales but added: "I am
not aware of any similar incident (having occurred) in the Bahamas."
He said further tests on the dead whales would be carried out in the United
States, a process that could take
months.
Smith said the exercise was testing for upgrades of what the Navy calls the
Directional Command Activated
Sonobuoy System.
The exercise involved a Navy P-3 aircraft dropping two buoys north of Abaco,
one as close as 35 miles to the
island, the other 70 to 75 miles from the island. One buoy emitted a sonar signal
which was received by the
other, and a submarine was moving between the two buoys.
He said the exercise had nothing to do with low frequency active sonar, a new
and controversial system that
transmits sonar pulses so loud they can match the roar of a rocket launch.
The U.S. National Marine Fisheries Service, responsible for overseeing all
U.S. actions that could affect the
environment at home or abroad, said it approved the Navy's environmental assessment
for its exercise.
Roger Gentry, coordinator of the service's acoustics team, said the exercises
shouldn't have affected the
whales. "Yet we have beached whales."
The service has also sent veterinarians and acoustic experts to investigate.
Marine scientists have been expressing growing concern in recent years about
the possible effects of
man-made noises on marine mammals who rely on their hearing perhaps more than
their sight.
"We already know from preliminary research that's been done that there
are some problems with man-made
noise in the marine environment," said Rose of the Humane Society.
However, other experts have been quick to point out that none of the research
has been able to conclusively
blame man-made noise for events such as the whale beachings in the Bahamas.
West Nile Virus...03/12/00
Nando News
ATLANTA (www.nandotimes.com) - Government researchers have
found that some mosquitoes hibernating in New York City this winter probably
are carrying the West Nile virus, which killed seven people in the area last
summer.
The Centers for Disease Control and Prevention said Thursday that mosquitoes collected at three of 69 sites in January and February had genetic material indicating the presence of the virus. Several thousand mosquitoes were tested. The virus itself was not detected in the three samples - numbering several dozen mosquitoes - but extremely sensitive testing found its genetic source.
The CDC said it is unclear whether the virus will persist or pose a health hazard in the spring and summer, when mosquitoes are active. "The bottom line here would be that we're not entirely certain what it means," said Dr. Stephen Ostroff, associate director of the CDC's National Center for Infectious Diseases.
In addition to the seven deaths, dozens more were infected by the virus, which can cause encephalitis, a dangerous swelling of the brain. People with weakened immune systems are at a higher risk. West Nile symptoms resemble severe flu, with fever often accompanied by poor muscle control or mental disorientation.