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: 3-D images of tiny objects down to 25 nanometres

Related Stories

Letting go of the (genetic) apron strings

Mar 20, 2015

A new study from Princeton University sheds light on the handing over of genetic control from mother to offspring early in development. Learning how organisms manage this transition could help researchers ...

From heat and cold comes image and mirror image

Mar 17, 2015

Many chemical compounds exist as an image and a mirror image: they differ in their spatial orientation, like the left and right hand. The properties of these so-called chiral molecules are also often quite different – synthesising ...

Supercomputers help solve puzzle-like bond for biofuels

Mar 16, 2015

One of life's strongest bonds has been discovered by a science team researching biofuels with the help of supercomputers. Their find could boost efforts to develop catalysts for biofuel production from non-food ...

Recommended for you

3-D images of tiny objects down to 25 nanometres

Mar 30, 2015

Scientists at the Paul Scherrer Institute and ETH Zurich (Switzerland) have created 3D images of tiny objects showing details down to 25 nanometres. In addition to the shape, the scientists determined how ...

Solving molybdenum disulfide's 'thin' problem

Mar 27, 2015

The promising new material molybdenum disulfide (MoS2) has an inherent issue that's steeped in irony. The material's greatest asset—its monolayer thickness—is also its biggest challenge.

Snowflakes become square with a little help from graphene

Mar 25, 2015

The breakthrough findings, reported in the journal Nature, allow better understanding of the counterintuitive behaviour of water at the molecular scale and are important for development of more efficient techno ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.