Interesting article i thought some on the list would appreciate. Over
the next 100 years or less, it is looking increasingly bad for coral
reef systems worldwide. From a malacalogical perspective that's not
good, since so much of the world's molluscan diversity is connected with
reefs.

http://www.enn.com/top_stories/article/39272

What's Killing The Coral Reefs?

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The answer to what’s killing the world’s coral reefs may be found in a
tiny chip that fits in the palm of your hand.

Scientists at Lawrence Berkeley National Laboratory and the University
of California, Merced are using an innovative DNA array developed at
Berkeley Lab to catalog the microbes that live among coral in the
tropical waters off the coast of Puerto Rico. They found that as coral
becomes diseased, the microbial population it supports grows much more
diverse.

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It’s unclear whether this surge in microbial diversity causes the
disease, or is a result of it. What is clear is that coral disease is
accompanied by a microbial bloom, and the DNA array, called the
PhyloChip, offers a powerful way to both track this change and shed
light on the pathogens that plague one of the ocean’s most important
denizens.

“The PhyloChip can help us distinguish different coral diseases based on
the microbial community present,” says Shinichi Sunagawa, a graduate
student in UC Merced’s School of Natural Sciences who helped to conduct
the research. “This is important because we need to learn more about
what’s killing coral reefs, which support the most diverse ecosystem in
the oceans. Losing them is much more than losing a reef, it means losing
fish and marine mammals, even tourism.”

Worldwide, coral is threatened by rising sea temperatures associated
with global warming, pollution from coastal soil runoff and sewage, and
a number of diseases. The organism’s acute susceptibility to
environmental change has given it a reputation as a canary in the
coalmine: if it suffers, other species will soon follow.

Fortunately, there are ways to give coral a health checkup. Scientists
have recently learned that healthy coral supports certain microbial
populations, while coral inflicted with diseases such as White Plague
Disease support different populations.

Understanding these microbial shifts could illuminate the magnitude and
causes of coral disease, and possibly how to stop it, which is where the
PhyloChip comes in. The credit card-sized chip can quickly detect the
presence of up to 9,000 species of microbes in specially prepared
samples of air, water, soil, blood, and tissue. The chip is carpeted
with thousands of probes that scour a sample for the unique DNA
signatures of most known species in the phyla bacteria and archaea.
Specifically, the probes bind with a gene, called 16S rRNA, which is
present in all life.

Developed by Gary Andersen, Todd DeSantis, Eoin Brodie, and Yvette
Piceno of Berkeley Lab’s Earth Sciences Division, the PhyloChip offers a
quick and low-cost way to canvas environmental samples for the presence
of microorganisms.

“It’s a fast and inexpensive way to conduct a complete microbial
community assessment of healthy and diseased corals,” says DeSantis.

In this study, the PhyloChip was used in conjunction with a more common
technique, clone library sequencing, to analyze healthy and diseased
samples of the coral Montastraea faveolata, which were plucked from
reefs in the waters off Puerto Rico. The PhyloChip analyses, which were
conducted at Berkeley Lab, found more species than the slower and more
expensive clone sequencing technique.

But neither technique yielded what the scientists anticipated. The
diseased coral was expected to contain the pathogen Aurantimonas
corallicida because the coral exhibited symptoms identical to another
coral species stricken by the pathogen. In this case, however, A.
corallicida was not found.

“This means there are possibly other pathogens out there that we don’t
know about,“ says Sunagawa. “There are only a handful of known coral
pathogens, and we didn’t find the pathogen that causes a similar display
in a different species of coral.“

In addition, the scientists have yet to determine whether the microbial
bloom that accompanies coral disease causes the disease, or is caused by it.

“We need to determine what comes first: the disease or the microbial
population change,”� says DeSantis. “We don’t know if the
disease-associated microbial population kills the coral, or if the
microbes are simply feeding on dead coral tissue.”

Adds Sunagawa, “We have only recently realized how microbes, and
microbial diversity, play an important role in the health of coral
reefs. And the PhyloChip offers a great way to catalog the microbiota
associated with coral reefs around the world.”

 From a mild morning in New Scotland,
Ross mayhew,
http://www.schnr-specimen-shells.com/

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