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Intra-Wiki: ellingtonch339lsp2011

Text of the Question:
Undergraduates at the University of Arkansas and at the University of California-Berkeley have come up with two similar, novel methods for generating butanol as a biofuel. Draw the likely pathway from glucose to butanol in its entirety, including any cofactors or other substrates as necessary. Cite appropriate sources, especially literature sources. If you wish to believe the Internet, caveat emptor.

Text of the Question:
A) Viagra operates via a particular signal transduction cascade. Draw a detailed cartoon showing how viagra operates at the molecular level, including downstream signaling relevant to vasomodulaiton. B) One of our other fine Texas institutions has spun out a company, Neogenis. The product of this company, Neo40, acts on the same pathway you just drew, but by a very different mechanism. Draw the mechanism on the same diagram (hint: NO is a gas, but they aren't packaging it). C) Upstream of the Neogenis mechanism is another trendy thing, the "Mediterranean diet." How might it provide vasomodulation.

Part C
Endothelial nitric oxide synthase (eNOS) activity in cultured cells is increase in response to addition of thyme and wild artichoke extracts added //in vitro//. The presence of these extracts also increases the expression of eicosanoid prostacyclin.[9.c.1]

Prostacyclin is a prostoglandin which acts by exerting its influence against PGI receptor, a G-protein coupled receptor (resulting in modulation of cAMP, upregulation of inositol triphosphate). It is a potent vasodilator, plays a role in the inflammation responses and is a factor in edema, as well as acting to prevent thrombosis. It also inhibits platelet aggregation.[9.c.2]

The effect on eNOS apparently not due to an increase in the expression of eNOS, but rather due to an increase in its effectiveness. Curiously, this appears to only have resulted in a modest increase in cGMP expression within the cell.[9.c.1]