How basil gets its zingOctober 03, 2007LA JOLLA, CA - The blend of aromatic essential oils that gives fresh basil leaves their characteristic warm and sweet aroma is well characterized but not much is known about the enzymatic machinery manufacturing the odiferous mix. Researchers at the Salk Institute for Biological Studies and the University of Michigan followed their noses and solved part of the molecular puzzle. Their study, published in the Oct. 4 issue of the journal PLoS ONE, provides a three-dimensional snapshot of the enzyme basil Eugenol Synthase frozen in mid-action as it produces eugenol, the fragrant molecule responsible for basil's spicy overtones reminiscent of cloves and cinnamon. "This particular enzyme is very interesting since it belongs to a large family of enzymes that perform what we call 'household reactions' but, through evolutionary selection, acquired an additional and completely new function," says Howard Hughes Medical Institute investigator Joseph P. Noel, Ph.D, director of the Jack H. Skirball Center for Chemical Biology and Proteomics, who led the study.
"Eugenol Synthase takes a basic building block that is usually employed to make wood and turns it into something that is almost the complete opposite of wood - a volatile molecule that easily becomes airborne, is highly aromatic and possesses antimicrobial and pain-dulling properties," marvels Noel. Traditionally, plant biology has been focusing on genetic approaches but in recent years plant biochemistry has been undergoing a sort of renaissance, not least because the natural food movement sparked newfound interest in the health-promoting and medicinal properties of natural plant chemicals. "Plant genetics uncovered a lot of genes with important functions but ultimately we need to understand how these systems work at a biochemical level," notes Noel. "We are consuming all these chemicals as part of our diet, some of which are very beneficial, preserve our food and impart some really interesting flavors and fragrances for our taste buds and noses, but some of which are toxic." Plants rely on a complex set of bioactive volatile chemicals, which diffuse easily through the membranes of cells that produce them to communicate and interact with the outside world. These often aromatic and highly specialized compounds entice pollinators, fend off pathogens, bacteria, and leaf-munching animals alike. Since antiquity, humans have exploited both the antimicrobial properties and pleasing aromas and flavors of plants rich in certain secondary metabolites - better known as spices - to preserve and flavor food. The food-preserving and analgesic properties of eugenol-rich cloves lured explorers like Ferdinand Magellan and Christopher Columbus across the seas in search of new routes to the Far East, which was, at the time, the sole source of cloves. Although Columbus never reached India, he did discover the Americas and, incidentally, found the source for a new spice, allspice, which contains the closely related chemical isoeugenol. In an earlier study, also performed by the collaborative team led by Dr. Noel and University of Michigan plant biochemistry professor Eran Pichersky, the enzymes that synthesize eugenol and isoeugenol from biosynthetic precursors of the plant polymer lignin, the "woody" component of trees, were identified. But how the enzymes accomplished their task at the molecular level remained unclear. With the help of x-ray crystallography and a small chemical - custom-tailored by senior staff chemist Thomas J. Baiga in Noel's lab -the research team was able to lock basil eugenol synthase in mid-reaction thereby capturing a detailed, three-dimensional view of the enzyme's interaction with its substrate and vitamin co-factor. "The enzyme utilizes an unusual mechanism involving two distinct steps," explains HHMI research specialist and first author Gordon V. Louie, Ph.D. "A subtle change in the substrate binding site after natural selection during the course of plant evolution added the capability to form a reactive intermediate through a concerted push-pull mechanism, which facilitates the second chemical step, a classic reduction reaction carried out by many evolutionary relatives of eugenol synthase." The next step for Noel, Pichersky and their research teams will be to compare eugenol synthases and closely related synthases making natural chemicals similar to eugenol from a wide variety of plants. "It allows you to peer back in time and see how these systems arose and how they are used in the present day." Understanding the biosynthetic pathways used by plants to make all of these secondary metabolites may help the Noel-Pichersky research team and others to improve the flavor and nutritional quality of plants that are part of our diet. Being able to tinker with natural scents could resurrect the waning scent of roses or create novel fragrances for the perfume industry. But scent engineering has the potential to do more than just pleasing human noses. It could increase crop yields by enticing new pollinators or natural pest controllers such as parasitic wasps to visit commercially grown plants. Salk Institute Science News and Science Current Events Tag Cloud This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size. Substance Abuse Incontinence Uterine Fibroids Post-traumatic Stress Biofilm Computer Chip CPAP Ankylosing Spondylitis Acid Rain Calorie restriction Mental Health Wireless sensor Mitochondrial Colonoscopy Learning Cholera Brain Neural Stem Cells Taste Postpartum Depression Mad Cow Disease Dengue Fever Silicon Immune Response Omega-3 Fatty Acids
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Related Basil Current Events and Basil News Articles Syracuse University researchers discover new way to attack some forms of leukemia Each year, some 29,000 adults and 2,000 children are diagnosed with leukemia, a form of cancer that is caused by the abnormal production of white blood cells in the bone marrow. New approach to protect the hearts of patients with muscular dystrophy A team of researchers has recently shown that the administration of sildenafil protects the heart in mice with Duchenne muscular dystrophy. International health experts to enlist the public in war on African malaria Philanthropy just got easier and a lot more accessible to the public thanks to the social networking power of the Internet and a ground-breaking partnership between a young British entrepreneur, a global health think tank and an African medical research institute. Nanotube forests grown on silicon chips for future computers, electronics Engineers have shown how to grow forests of tiny cylinders called carbon nanotubes onto the surfaces of computer chips to enhance the flow of heat at a critical point where the chips connect to cooling devices called heat sinks. Baumann Lab Defines Proteins that Distinguish Chromosome Ends from DNA Double-Strand Breaks Peter Baumann, Ph.D., Assistant Investigator, and Nancy Bae, Ph.D., Postdoctoral Research Associate in the Baumann Lab, have published a paper offering insight into the way cells protect chromosome ends from misguided repair. M. D. Anderson teaches the art of aromatherapy to soothe and heal A bubble bath that improves memory. A kitchen cleaner that wards off nausea and energizes. A scented handkerchief that calms a patient entering the MRI. The benefits of aromatherapy are real. Below, learn the uses, healing properties and how-tos of using aromatherapy to heal and de-stress from The University of Texas M. D. Anderson Cancer Center in Houston. The Right Food Can Improve Fertility Roasted red peppers, mini crab cakes and Brazil nuts can all help to increase fertility. They will all feature in a special Fertility Buffet, laid on by Dr Margaret Rayman, Director of the MSc Course in Nutritional Medicine at the University of Surrey, on 3 July 2003. A good, balanced diet rich in fruit and vegetables (at least five portions a day) and protein sources such as meat, poultry and fish, is necessary to optimise fertility. Meat is a good source of animal protein and important minerals such as iron and zinc, the latter being especially important for fertility. "Oysters are by far the best source of zinc, but they are not included in this meal, as they are out of season," UK Companies encouraged to "Go for the Grid" UK companies are this week (5th and 6th September) given encouragement to build long term relations with CERN (the European Laboratory for Particle Physics) with a view to winning contracts, especially related to the GRID. Mr Basil Eastwood, Her Majesty`s Ambassador to Switzerland, and Professor Ian Halliday, Chief Executive of the Particle Physics and Astronomy Research Council (PPARC) will visit a number of companies to discuss the commercial opportunities available to them. CERN, the home of the World Wide Web, is currently leading the development of the DataGrid Project - the next generation computer infrastructure providing extensive computation and analysis of shared large-scale dat Italy now faces worldwide storm of protest over fertility proposals Italian legislators now face worldwide condemnation by fertility experts for IVF proposals that could encourage multiple pregnancies and put babies at risk. The International Federation of Fertility Societies (IFFS) has added its voice to that of the European Society of Human Reproduction and Embryology, who have already described the proposals as "disastrous". The Federation represents fertility specialists in 55 countries*. In a meeting yesterday (Tuesday 2 July) in Vienna the Executive Committee of IFFS discussed the legislation by the Lower House of the Italian Parliament, which would make the freezing of ooctyes and sperm acceptable, but ban the freezing of embryos - currently Students can celebrate northern region's writers A University of Sunderland academic has set up a new course which celebrates the richness, diversity and world renown of North-East and Cumbrian writers. English lecturer Dr Richard Terry has devised a course which will give a fascinating insight into the lives and works of acclaimed writers in the region over the last 1400 years - from Bede, Wordsworth and Lewis Carroll through to Catherine Cookson and Pat Barker. The course will explore the impact North-East and Cumbrian writers have had on the region - how they have shaped our social, political and economic landscape, as well as how the region has benefited commercially from them. Other writers who will figure in the course include Whitby More Basil Current Events and Basil News Articles |
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