The group also is exploring how various molecules affect the self-assembly chemistry and how to make the spheres monodispersive.
"We're now trying to make the chemistry such that the spheres will all be the same size. And we're on the right track," says
Wong.
—Kaylynn Chiarello
1An in-depth discussion of the methodology is presented elsewhere (Adv. Mater.
17, 1145-1150 [2005]).
FORMULATION
It Helps to be Flexible: Supple WIN Compounds Could Cure the Common Cold
A wiggling WIN antiviral compound (which received its name from the former Sterling-Winthrop company) could be the answer
for fighting the common cold, says a team of Purdue University (West Lafayette, IN,
http://www.purdue.edu/) researchers.
The rhinovirus—one cause for the common cold—has two main properties that make it difficult to stop. First, the virus can
go incognito by subtly changing its surface structure and making it undetectable by the body's immune system. Second, after
the virus enters the cell, it opens up a trap door to unleash RNA that instructs the cell to produce more rhinovirus particles.
A small, cigar-shaped cavity located in the folds of the VP-1 protein on the viral shell helps guide these changes. Filling
this crevice prevents the virus from shape shifting and is the key to curing the cold, say the Purdue researchers. "What we'd
like to do is find something that will stabilize these VP-1 proteins so the trap door can't open, and WIN compounds are potential
compounds for the job," said Carol B. Post, professor at Purdue, in a press release.
By using computer simulations of the molecule's structure, the team has discovered that the WIN compound's flexible nature
allows it to wiggle into this gap. Once inside the cavity, the molecule affects the VP-1 protein's rigidity, thereby deactivating
the virus. Said Post, "In essence, the compounds can get tangled up in the protein so it can't move enough to let the RNA
out. One reason WIN compounds are promising is that they are very good at getting to the spot where they can tangle up the
protein effectively, which turns out to be a tricky business."
Researchers speculate the stiffness may also inhibit the virus from opening its trap door because, just as people don't like
exercising after a big meal, "having a WIN compound in its cavity may be the VP-1 protein's equivalent of having an overly
full stomach," noted Post.
—Kaylynn Chiarello
|
