Although a number of new antibiotics have been discovered in recent decades, our armory against infection is continually being depleted, as our microscopically small enemies are crafty warriors that develop resistance to current antibiotics.
Multiresistant bacteria are a big problem, especially in hospitals. Already weakened patients are easy victims, for which an infection that cannot be treated with antibiotics can quickly become life-threatening. What is needed are active agents that act on completely different sites in the physiological sequence of pathogens than current medicaments. Platensimycin, recently isolated from the mushroom Streptomyces platensis, is such an agent. A Californian team of researchers is now the first to synthesize this natural product completely in the laboratory—a crucial step on the way to a new class of antibiotics.
Platensimycin inhibits an important step of bacterial fatty acid biosynthesis and in this way paralyzes a broad spectrum of Gram-positive bacterial strains. Thus, this natural product in able to kill dangerous germs that have developed resistance not only to established antibiotics but also to standby products. Examples of these include various resistant strains of Staphylococcus aureus and Enterococcus faecium.
To isolate a complex natural product in sufficient quantity and purity for further experiments is usually a difficult and time-consuming, if not impossible, task. Chemists thus follow a different path: They reproduce the natural product in the laboratory from the ground up. This approach is known as total synthesis. To devise such a total synthesis is an enormous scientific challenge. A way must be found to assemble a complicated synthetic molecule faultlessly from simple, available components—and in sufficiently high yield in each reaction step. The total synthesis of platensimycin has now been accomplished by a team headed by the renowned natural products chemist K. C. Nicolaou (The Scripps Research Institute, La Jolla, and University of California, San Diego). Platensimycin consists of an unusual aromatic ring coupled through an amide group to a compact cage structure. The team built these two components—each a veritable challenge for synthetic chemists—separately and then joined them in the final step of the synthesis. "The described chemistry," says Nicolaou, "sets the stage for the synthesis of designed analogues for structure–activity relationship studies in the search for new antibacterial agents."
K.C. Nicolaou, Ph.D. | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine