ACS News Service Weekly PressPac: May 16, 2007

• Equipping E. Coli With A “Chemo-Navigation” System
• Crusts from the Tower Of London Suggest Yellowing In The Future
• Scientists Isolate Anti-Cancer Compounds from Apple Peel
• New Medications Needed For Neuropathic Pain
• Western Drug Makers Expand Use of India’s Scientific Talent

In genetic engineering’s version of the Pied Piper, chemists have programmed E. coli bacteria to move toward new chemical signals — an advance they say could enable the production of bacteria with important uses in medicine, environmental clean-ups, and other fields.

“Equipping bacteria that can degrade pollutants, synthesize and release therapeutics, or transport loads with an ability to localize to a specific chemical signal would open new frontiers in bioremediation, drug delivery, and synthetic biology,” Emory University’s Justin P. Gallivan and Shana Topp state in the study. It is scheduled for publication in the June 6 issue of the Journal of the American Chemical Society, a weekly publication.

Gallivan and Topp manipulated the natural chemotaxis ability of E. coli, which enables certain microbes to move toward chemicals in their environment. Researchers have envisioned reprogramming such organisms so that microbes capable of synthesizing an anti-cancer drug, for instance, can be used to medicate diseased cells while sparing healthy cells of side effects.

The researchers gave E. coli a “riboswitch,” a segment of RNA that changes shape when bound to certain small molecules and then turns genes on or off. They believe that approach can be used to equip motile bacteria with “chemo-navigation” systems to move toward desired targets.

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Doctor Mom’s admonition, “Don’t peel your apple,” is getting new scientific support from scientists in New York, who are reporting isolation of chemical compounds from apple peel that may be involved in the apple’s beneficial health effects. Their report is scheduled for publication in the [date TC] issue of ACS’s Journal of Agricultural and Food Chemistry.

In the study, Rui Hai Liu and Xiangjiu He point out that apple consumption has been linked to a reduced risk of chronic health problems such as lung cancer, heart disease, and stroke. Traditional advice on eating apple peel was based mainly on its fiber content, with peel packing about 75 percent of the dietary fiber in an apple. More recently, however, scientists have shown that the peel also contains most of the beneficial phytochemicals believed to be responsible for the apple-a-day-keeps-the-doctor-away effect.

Until now, however, scientists had not identified the specific phytochemicals responsible for apple’s anti-cancer effects. Xiangjiu He and Liu processed 231 pounds of Red Delicious apples and extracted phytochemicals from about 24 pounds of peel. They screened the compounds for anti-cancer effects in laboratory cultures of human liver, breast, and colon cancer cells. In doing so, they identified a group of compounds with “potent” anti-cancer effects.

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India is quietly assuming a new and expanded role in the discovery and development of medicines for patients in the United States and other western countries, according to an article scheduled for the May 21 issue of Chemical & Engineering News (C&EN), ACS’ weekly newsmagazine.

In the article, Jean-Franåois Tremblay, of C&EN’s Asia-Pacific Bureau, explains that big western pharmaceutical companies long have turned to India’s numerous contract research firms to work on specific, well-defined projects. “But for the past two years, the country’s research service providers have begun to undertake far more significant drug discovery work for foreign clients,” the article notes.

Driving the new wave of pharma outsourcing in part is India’s huge pool of English-speaking scientists, particularly synthetic organic chemists, many of whom are highly motivated and willing to work for a fraction of the salary of similarly-trained sciences in the U. S., Europe, or Japan, the article states. India’s top research providers also are creating a climate of confidentiality that gives western drug makers assurance about protection of their trade secrets, it adds. Tremblay includes specific examples of western drug makers that are expanding use of that scientific manpower by forming external alliances in India to increase R&D productivity.

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• General Chemistry Glossary
  The General Chemistry Glossary can be found here.
• Science Elements: ACS Audio Clips
  Listen to Science news podcasts from the American Chemical Society.
• News, Features, Background, Sources from ACS National Meeting
  News media resources from the March 25-29 meeting in Chicago include more than 9,000 abstracts of technical presentations and more than 1,000 non-technical summaries in a searchable database, plus press releases, podcasts, and other material. If you are researching or sourcing stories on chemistry-related topics, this resource can be a treasure trove accessible by the following:
  ACS News Service’s National Meeting Press Book page
  ACS Chicago National Meeting News Page
  ACS Press Center
• Green Goals for the Pharmaceutical Industry
  The ACS Green Chemistry Institute Pharmaceutical Roundtable has developed a list of priority research areas where “green” alternatives to conventional reactions are needed to develop medications with minimal impact on the environment. Their review paper, describes and prioritizes research needs. It can be a valuable resource for journalists writing about green chemistry. Although the paper focuses on pharmaceuticals, it includes reactions and processes used by the broader chemical enterprise.

The Philadelphia Section, American Chemical Society, and Ursinus College will host the 39th ACS Middle Atlantic Regional Meeting.

This pioneering conference on one of the hottest topics in chemistry will be held June 26-29, 2007 at the Capital Hilton hotel in Washington, DC.

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