Scientists watch on the atomic level how individual molecules recognize each other

May 02, 2007

The body is an almost perfect machine. For it to function properly, each individual component, that is each molecule, must reliably fulfill its specific function. Each molecule must thus “recognize” other molecules and work with them. A team of researchers from the Max Planck Institute for Solid State Research in Stuttgart, the Fraunhofer Institute in Freiburg, and King’s College in London, has now successfully filmed pairs of molecules during the recognition process. As reported to the journal Angewandte Chemie, the shapes of the molecules change to accommodate each other.

Like humans, molecules also “greet” each other with a kind of “handshake”. Anyone who has tried to shake someone’s right hand with his or her own left will have had a little trouble: the right and left hands do not fit together. In the same way, some molecules that exist in both a right-handed (D) and left-handed (L) configuration can tell if others they encounter are the D or L form.

Magali Lingenfelder and colleagues at the Max Planck Institute for Solid State Research have now been able to use scanning tunneling microscopy to take a series of pictures that follow in detail the “encounters” of diphenylalanine molecules adsorbed onto a substrate. (Diphenylalanine is the central structural unit within polypeptide fibers found in the brains of Alzheimer’s patients.) The “film sequences” reveal that only molecules with the same chirality (handedness) readily aggregate into pairs and chains.

Just as in a handshake, it is not enough that the right hands hold each other. To grip each other firmly, the two hands must adapt to fit their shapes together. Molecules do the same: close examination of the “film”, in conjunction with theoretical calculations by researchers from King’s College, prove that this type of dynamic accommodation of shape also occurs when two molecules “shake hands”.

“Our work finally demonstrates that Linus Pauling was right with his theory of intermolecular conformation of over 50 years ago,” says Lingenfelder. “In molecular recognition, it is not so much the static forms that are important, but rather how well the molecules can conform to each other.”

Citation: Magalí Lingenfelder, Tracking the Chiral Recognition of Adsorbed Dipeptides at the Single-Molecule Level, Angewandte Chemie International Edition, doi: 10.1002/anie.200700194

Source: Angewandte Chemie

Explore further: Team finds electricity can be generated by dragging saltwater over graphene

add to favorites email to friend print save as pdf

Related Stories

New study outlines 'water world' theory of life's origins

11 hours ago

(Phys.org) —Life took root more than four billion years ago on our nascent Earth, a wetter and harsher place than now, bathed in sizzling ultraviolet rays. What started out as simple cells ultimately transformed ...

Astronomers suggest more accurate star formation rates

Apr 10, 2014

(Phys.org) —Astronomers have found a new way of predicting the rate at which a molecular cloud—a stellar nursery—will form new stars. Using a novel technique to reconstruct a cloud's 3-D structure, ...

Quantum melting

Apr 07, 2014

When ice is warmed, the water molecules forming its structure vibrate more and more vigorously until finally the forces between them are no longer strong enough to hold them together – the ice melts and ...

Recommended for you

First direct observations of excitons in motion achieved

Apr 16, 2014

A quasiparticle called an exciton—responsible for the transfer of energy within devices such as solar cells, LEDs, and semiconductor circuits—has been understood theoretically for decades. But exciton ...

User comments : 0

More news stories

Thinnest feasible nano-membrane produced

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

Researchers discover target for treating dengue fever

Two recent papers by a University of Colorado School of Medicine researcher and colleagues may help scientists develop treatments or vaccines for Dengue fever, West Nile virus, Yellow fever, Japanese encephalitis and other ...