News From The American Chemical Society
Journal of Physical Chemistry B
Scientists are reporting evidence that intact, double-stranded DNA has the "amazing" ability to recognize similarities in other DNA strands from a distance. And then like friends with similar interests, the bits of genetic material hangout or congregate together. The recognition - of similar sequences in DNA's chemical subunits - occurs in a way once regarded as impossible, the researchers suggest in a study scheduled for the Jan. 31 issue of ACS' Journal of Physical Chemistry B.
Geoff S. Baldwin, Sergey Leikin, John M. Seddon, and Alexei A. Kornyshev and colleagues say the homology recognition between sequences of several hundred nucleotides occurs without physical contact or presence of proteins, factors once regarded as essential for the phenomenon. This recognition may help increase the accuracy and efficiency of the homologous recombination of genes - a process responsible for DNA repair, evolution, and genetic diversity. The new findings thus may shed light on ways to avoid recombination errors, which underpin cancer, aging, and other health problems.
In the study, scientists observed the behavior of fluorescently tagged DNA strands placed in water that contained no proteins or other material that could interfere with the experiment. Strands with identical nucleotide sequences were about twice as likely to gather together as DNA strands with different sequences. "Amazingly, the forces responsible for the sequence recognition can reach across more than one nanometer of water separating the surfaces of the nearest neighbor DNA," said the authors. - AD
ARTICLE: "DNA Double Helices Recognize Mutual Sequence Homology in a Protein Free Environment"
CONTACT: Geoff S. Baldwin, Ph.D.
Imperial College of London
London, U.K.
Sergey Leikin, Ph.D.
National Institute of Child Health and Human Development
National Institutes of Health
Bethesda, Maryland 20892
Secret of the carnivorous pitcher plant's slurp - solved at last
Journal of Proteome Research
Splash! Ooch! Yum! And so another unsuspecting insect victim of Nepenthes alata (N. alata), commonly known as the carnivorous pitcher plant, falls victim to the digestive fluids at the bottom of the plant's famous cup-shaped leaf. For almost a century, scientists have sought the full chemical recipe for the pitcher plant's fluid. Japanese scientists now report completely deciphering this complex cocktail of digestive and antibacterial enzymes. Their study is scheduled for the February issue of ACS' Journal of Proteome Research, a monthly publication.
Unlike other plants that absorb nutrients from the soil, carnivorous plants growing in nutrient-poor soils have special organs to capture insects, digest them and absorb the nitrogen and phosphorous their environment sorely lacks. The identity of all the myriad proteins involved in this evolutionary marvel - some of which could have beneficial applications in medicine and agriculture - has been a mystery until now.
Tatsuro Hamada and Naoya Hatano used cutting-edge proteomic analysis to identify all of the components. They isolated and sequenced the proteins, then compared each with existing proteins to find structural matches. Hamada and Hatano detected seven proteins that exist mainly in the pitcher fluid of N. alata - three of which can only be found in this species - including useful enzymes that may inhibit bacterial growth and rotting as the plant slowly digests its prey. - AD
ARTICLE: "Proteome Analysis of Pitcher Fluid of the Carnivorous Plant Nepenthes alata"
CONTACT: Tatsuro Hamada, Ph.D.
Ishikawa Prefectural University
Ishikawa, Japan
Toward a cleaner, more effective method for destroying hormone-like pollutants in wastewater
Environmental Science & Technology
Researchers report effectiveness of a powerful, environmentally-friendly catalyst in destruction of various estrogens that currently escape complete removal in our wastewater treatment plants. Their study is scheduled for the Feb. 15 issue of ACS' Environmental Science & Technology, a semi-monthly journal.
In the new study, Nancy Shappell and colleagues explain that endocrine disruptors, both natural hormones and hormone-like compounds, have been detected in the surface waters. Many of these endocrine disruptors have estrogenic activity. Ethinylestradiol, for instance, is an active ingredient in both the birth control pill and the newly-introduced "no period pill." It is a major source of environmental estrogenic activity.
To address this problem, the researchers tested a new catalyst called Fe-TAML or Fe-B*. In the presence of hydrogen peroxide, the catalyst quickly and effectively destroyed various forms of estrogens typically found in post-treatment wastewater, removing 95 percent of the chemicals - including Ethinylestradiol - in 15 minutes. Estrogenic activity was also diminished to a similar extent. Further research will evaluate Fe-B*'s efficacy on actual wastewater, in addition to more extensive evaluation of byproduct toxicities. Usefulness in wastewater treatment could be doubly beneficial, as Fe-B* has been reported to destroy harmful bacterial spores. - MTS
ARTICLE: "Destruction of estrogens using Fe-TAML/peroxide catalysis"
CONTACT: Nancy Shappell, Ph.D.
USDA-Agricultural Research Service
Fargo, North Dakota 58105
Converting sewage into drinking water: Wave of the future?
Chemical & Engineering News
Amid growing water shortages in parts of the United States, more communities are considering tapping their sewage treatment plants as a new source of drinking water. The conversion of wastewater into tap water could help meet increased demand for one of life's most essential resources, according to an article [http://pubs.acs.org/cen/science/86/8604sci4.html] scheduled for the Jan. 28 issue of Chemical & Engineering News, ACS's weekly newsmagazine.
C&EN Associate Editor Jyllian Kemsley notes in the article that some communities have used recycled wastewater for decades to replenish their drinking water supplies and wastewater often finds agricultural use for irrigation. Droughts, environmental concerns, and population growth now are forcing water utilities to consider adapting or expanding the practice, Kemsley explains.
Earlier in January, for instance, California approved operation of the Advanced Water Purification Facility (AWPF), the largest water reclamation plant in the nation. It will yield 70 million gallons per day of drinkable water from sewage. That's about 10 percent of the district's daily water demand for its 2.3 million residents. Although AWPF's purification process is complex, it produces clean, pure water that meets or exceeds all drinking water standards, the article notes.
ARTICLE: "Treating Sewage For Drinking Water"
CONTACT: Michael Bernstein
ACS News Service
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Article adapted by Start Sanatate from original press release.
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The American Chemical Society - the world's largest scientific society - is a nonprofit organization chartered by the U.S. Congress and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
Source: Michael Woods
American Chemical Society
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