Navigation Links
Scientists get best look ever at water-life connection

snapshots of water molecules moving around a protein taken from a common bacterium, Staphylococcus.

The key to getting a good view of the interaction was to precisely locate an optical probe on the protein surface. They inserted a molecule of the amino acid tryptophan into the protein as a probe, and measured how water moved around it -- a technique Zhong began to develop when he was a postdoctoral researcher in Nobel laureate Ahmed Zewail's lab at the California Institute of Technology 5 years ago.

Laser studies of the protein while it was immersed in water revealed that far away from the protein -- in a region Zhong called "bulk water" -- the water molecules were flowing around each other at their typically fast speeds, with each movement requiring only a single picosecond.

But the water near the protein formed several distinct layers. The outermost layer flowed at a slower speed than in bulk water, and the innermost layer even slower. In that innermost layer, each movement of a water molecule to connect with the protein required at least 100 picoseconds to complete.

So when it comes to supporting life -- on the molecular scale, anyway -- water has to move 100 times slower to get the job done.

"The fast-moving water has to slow down to connect with a slow-moving protein -- it's that simple," Zhong said.

"It sounds trivial, I know. But it should be trivial.

"It's an essential biological interaction that has to work just right every time. If the water moved too slowly, it could get in the way of proteins trying to meet -- it would be a bottleneck in the process. And if it moved too fast, it couldn't connect with the protein at all. So I think this is nature's way of getting the interaction just right."


'"/>

Source:Ohio State University


Page: 1 2

Related biology news :

1. Scientists ID molecular switch in liver that triggers harmful effects of saturated and trans fats
2. Scientists Replicate Hepatitis C Virus in Laboratory
3. Scientists detect probable genetic cause of some Parkinsons disease cases
4. Scientists find missing enzyme for tuberculosis iron scavenging pathway
5. Scientists seek answers on what activates deadly anthrax spores
6. Yale Scientists Find MicroRNA Regulates Ras Cancer Gene
7. Scientists collaborate to assess health of global environment
8. Scientists decipher genome of fungus that can cause life-threatening infections
9. Scientists discover the cellular roots of graying hair
10. Scientists rid stem cell culture of key animal cells
11. Scientists develop new color-coded test for protein folding
Post Your Comments: