A new potential drug from a marine microorganism is effective against anthrax and various other Gram-positive bacteria, as reported by American scientists in the journal Angewandte Chemie. A chlorinated analogue kills off Gram-negative bacteria.
Anthrax is a dangerous infectious disease caused by the spore-forming bacterium Bacillus anthracis and transmitted by infected farm animals. For several years now, anthrax has also been feared as a biological weapon. Attacks with spore-containing letters caused five deaths in 2001.
Infection with anthrax usually requires tedious treatment with various antibiotics. Infections caught through the respiratory system are especially dangerous, often requiring continuous intravenous antibiotics. The search for effective antibiotics is thus correspondingly important.
Researchers working with William Fenical have now isolated a species of Streptomyces from near-shore sediments near Santa Barbara, California. The culture extracts demonstrate significant activity against anthrax. The team from the University of California, San Diego and Trius Therapeutics (San Diego) succeeded in isolating a molecule from this extract that kills off anthrax bacteria as well as other Gram-positive bacteria like staphylococci, enterococci, and streptococci. However, it is virtually useless against Gram-negative bacteria.
By using a variety of methods of analysis, the researchers were able to determine the structure of this molecule, which they named anthracimycin. Anthracimycin contains an unusual system of rings, one with fourteen carbon atoms and two with six each. This is a macrolide whose biosynthesis very likely occurs by the polyketide pathway. X-ray crystallographic studies allowed the researchers to determine the absolute configurations of the seven asymmetric carbon centers in this compound, identifying the complete 3-dimensional structure.This class of molecules is completely different from all known antibiotics. An similar carbon skeleton is found in chlorotonil, a metabolite from the terrestrial myxobacterium Sorangium cellulosum. However, chlorotonil differs in its carbon skeleton, contains two chlorine atoms and the stereochemistry of most of its asymmetric carbon centers differs from that of anthracimycin.
In order to examine the effects of the chlorine atoms in the close analogue chlorotonil, the scientists chlorinated anthracimycin.
This chlorine-containing analogue proved to be only about half as effective against B. anthracis. However, its activity against a number of Gram-negative pathogens increased significantly. This finding is important because Gram-negative bacteria are often resistant to current antibiotics. Comprehensive studies of this new class of antibacterials could lead to the development of effective new drugs.About the Author
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201302749
William Fenical | Angewandte Chemie
New insights into the information processing of motor neurons
22.02.2017 | Max Planck Florida Institute for Neuroscience
Wintering ducks connect isolated wetlands by dispersing plant seeds
22.02.2017 | Utrecht University
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
22.02.2017 | Power and Electrical Engineering
22.02.2017 | Life Sciences
22.02.2017 | Innovative Products