King Abdullah University of Science and Technology at Thuwal, Kingdom of Saudi Arabia
BE the
March 2011 / Rabi-I 1432 Issue No. 7
CON www.kaust.edu.sa
Bio-organometallic Catalysis
Explore Explore our neighbor Thuwal
Turn to p. 4–5
Over billions of years, evolution has provided amazing solutions for life’s many challenges. One of these is the group of naturally occurring catalysts – enzymes. These remarkable biocatalysts can be further developed to provide a more environmentally friendly and cost-competitive type of catalysis – becoming a “green” alternative to synthetic chemistry. Unlike the toxic chemicals often associated with industrial catalysis, naturally occurring enzymes can offer unsurpassed selectivity and activity in very mild conditions. The attraction of using this more natural approach has been reflected in the increased global share of biocatalysis in fine chemical production up from 7% in 2000 to over 25% in 2010 and expected to double in the next five years. However, nature’s catalysts still have some weaknesses: there are a limited number of enzymes and they are optimized to work under physiological conditions. The challenge is to mimic the diversity offered by modern synthetic chemistry using biocatalytic methods. At KAUST, Professor Jörg Eppinger and his interdisciplinary research team set out to unite the two scientific worlds of biotechnology and homogeneous catalysis by providing nature with novel tools that capitalize on the advantages of both sciences. New types of catalysts will emerge, which provide the reaction diversity of artificial as well as the selectivity and environmental friendliness of biocatalysts. One huge hurdle has to be overcome. In stark contrast to artificial organometallic catalysts, which require rigorous exclusion of moisture and air, functional biocatalysts often need water and oxygen. Initially, Prof. Eppinger’s research team developed organometallic catalysts motives, highly active in water and air at room temperature. In two recent papers in Green Chemistry, Alexander Marziale, a PhD student in Prof. Eppinger’s group described an efficient protocol for palladium-catalysed Suzuki-Miyaura cross-coupling in these mild conditions to isolate over 50 different pure products by using simple filtration. The publications stirred great interest in the scientific community as they reflect the recent focus on the more sustainable use of resources. What is palladium and what does cross-coupling mean? Cross-coupling is a tool in synthetic chemistry that allows for the artificial formation of bonds between carbon and nonmetal elements. Being able to make such bonds is the basis of nature’s amazing diversity such as flower color, and this Continued on p.2
Pigeye
Shark
Two observant KAUST students who spotted a shark that seemed unfamiliar in a Jeddah fish market are authors on a paper currently in press in the journal Zoology in the Middle East. The paper, written jointly with their supervisor, Professor Michael Berumen, describes a "range extension" of this species - previously unknown in the Red Sea. Julia Spaet and Jesse Cochran purchased the shark suspecting that they had chanced upon something unusual, and further examined it back at KAUST to establish that it was indeed a juvenile Pigeye Shark.
With this new finding, there are now 29 species of shark reported to inhabit the Red Sea ranging from small reef sharks (about 1m in length) to whale sharks which can grow up to 18m. These sharks are almost always benign, attacking people rarely and for reasons that no one has been able to establish. Be reassured that statistically, you are more likely to be killed by a coconut falling on your head than by an attack from a shark! This particular specimen was caught on a hand line about 300km south of Jeddah. Sharks actually predate trees, first appearing some 400 million years ago, and they have changed remarkably little since. Their
cartilaginous skeleton not only makes them lighter in weight, but more flexible. Shark teeth seem to have evolved from their dermal denticles – the rough, sharp protrusions that is one of the distinguishing features. Should you choose to run your hand over a shark’s skin, you would find it has a nap – like velvet - smooth as silk in one direction, and well capable of cutting your palm in the other. Teeth vary from species to species: some flat to crush crustaceans for food; others long and pointed to allow smaller fish to be captured; others serrated and triangular so that the shark can tear chunks of flesh from larger prey. The benign whale shark barely has teeth as it feeds by filtering plankton. Unlike most other fishes, salt levels in the blood of sharks are equivalent
to those in salt water and the shark uses urea to regulate the level; bull sharks can actually move from salt water to fresh water by regulating their blood salt levels by increasing diuresis. Unfortunately the urea accumulates in the flesh of shark meat; unless bled immediately it has a noxious taste and smell. Anyone who has visited the Red Sea Research Center’s lab following a shark dissection can attest to this powerful odor! Additionally, mercury levels are such that one 300g shark steak provides the lifetime tolerance limit. That said, sharks are threatened because the cartilage from their fins gives soup an unusual texture considered exquisite by some, thus leading to the disappearance of 85% of species in the South China Sea, for example. By some estimates, something between 1 million and 100 million sharks are harvested globally each year. Continued on p.2
INSIDE:
News 1-2
Blue Brain Project 3
Thuwal Tour 4-5
Research 6-7
Community 8