Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen – and not deadly carbon monoxide – preferably binds to the proteins that transport it around the body.

Abstract:
Physicists have created a unique combination of computer models, based on the theory of quantum mechanics, and applied them to a previously well characterised protein found in muscle to develop a new picture of how biomolecules transport and store oxygen (O2). In doing so, the international team have shown how the process of respiration, which is fundamental in humans and other vertebrates, exploits quantum mechanical effects working on tiny scales.

Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen – and not deadly carbon monoxide – preferably binds to the proteins that transport it around the body.

Dublin, Ireland | Posted on July 17th, 2014

The physicists' discovery, building on a number of years of intense collaboration on theory and software development, has solved a long-standing problem at the interface of chemistry and biology. At the same time, they have demonstrated a new way by which quantum mechanics can be used to answer biochemical questions, with implications for inspiring drug-related research and further interdisciplinary collaborations.

Assistant Professor in Physics in the School of Physics at Trinity College Dublin, Dr David O'Regan, said: "This work helps to illustrate the fact that quantum mechanical effects, which may sometimes be viewed as somehow very exotic or only relevant under extreme conditions, are at play in the day-to-day regimes where biology, chemistry and materials science operate."

Iron-containing proteins, such as ‘myoglobin' play a central role in biochemistry. Their ability to reversibly bind small molecules (such as O2) is vital for life. All animals must transport such molecules through the blood stream to where they are needed around their bodies, and myoglobin is particularly important in vertebrates. These proteins can also bind to other simple molecules such as carbon monoxide (CO), however. This is very dangerous in the case of the iron-containing proteins involved in respiration, since such a union is irreversible and leads to the protein being poisoned and the individual ultimately asphyxiating.

Until now, computational scientists have been unable to come to a good understanding of exactly why such protein poisoning is not more common. More specifically, computer simulations using the most widely-used theoretical approach (density-functional theory, ‘DFT') that won the Nobel Prize for Chemistry in 1998, as well as many of its more advanced extensions, consistently predict that CO should bind to myoglobin much more readily than O2 when the two molecules are both present. If this was to happen in reality, we would not even be around to wonder why.

The mismatch between previous predictions and what we observe in nature prompted the team of physicists to develop a new approach to understand the process of how myoglobin preferentially binds to O2, and not CO. They combined their expertise in simulating both large systems and advanced approximations in quantum physics to reach their goal.

Dr O'Regan and his international collaborators used a special variety of DFT that is optimised for large systems (and on which Dr O'Regan has worked for a number of years) to model a large myoglobin structure. They also used another advanced approach, targeting the all-important iron atom, to treat some of the more complex interactions between its electrons.

It turns out that some electrons in the myoglobin involved in binding CO and O2 exhibit a strong ‘entanglement' effect, which means that their motion cannot be described independently. The all-important strength of this effect is primarily controlled by a property of quantum mechanics (Hund's exchange) that has been traditionally neglected in such simulations; the team now believe that classical electric repulsion effects are far less important in determining which of CO and O2 is more energetically favourable for binding.

Dr O'Regan said: "We have succeeded in showing that quantum mechanical effects that we more often think of arising in advanced technological materials can be critical in determining the energy differences that drive biochemical processes occurring in the body. It is remarkable that myoglobin seems to be extremely well adapted to exploit the specific Hund's exchange strength of atomic iron, an intrinsically quantum mechanical property, in order to strongly promote O2 binding at the expense of CO. It is interesting, perhaps, to take a step back and even think of the implications with regards to early natural selection."

He added: "Computer-based simulation using DFT, together with its extensions developed in this work, is a laboratory for studying these effects on atomic length-scales. Approaches such as these are becoming increasingly valuable, and widely used, in helping to tackle contemporary, even urgent problems in areas such as pharmacology, materials for energy storage and conversion, and nanotechnology."

####

For more information, please click here

Contacts:
Thomas Deane
Press Officer for the Faculty of Engineering, Mathematics and Science
Trinity College Dublin

Tel: +353 1 896 4685

David O’Regan
Assistant Professor in Physics
Trinity College Dublin

Tel: +353 1 896 3138

Copyright © Trinity College Dublin

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Related News Press

News and information

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Super stable garnet ceramics may be ideal for high-energy lithium batteries October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Physics

Solid nanoparticles can deform like a liquid: Unexpected finding shows tiny particles keep their internal crystal structure while flexing like droplets October 12th, 2014

Unconventional photoconduction in an atomically thin semiconductor: New mechanism of photoconduction could lead to next-generation excitonic devices October 9th, 2014

Nanoparticles Break the Symmetry of Light October 6th, 2014

Quantum environmentalism: Putting a qubit's surroundings to good use October 2nd, 2014

Software

How things coil: Researchers discover that simulation technology designed for Hollywood can be used as a predictive tool for understanding fundamental engineering problems September 29th, 2014

Terabyte Photonic Dataset Sale July 30th, 2014

A*STAR and industry form S$200M semiconductor R&D July 25th, 2014

New computer program aims to teach itself everything about anything June 12th, 2014

Announcements

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Super stable garnet ceramics may be ideal for high-energy lithium batteries October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Special UO microscope captures defects in nanotubes: University of Oregon chemists provide a detailed view of traps that disrupt energy flow, possibly pointing toward improved charge-carrying devices October 21st, 2014

Could I squeeze by you? Ames Laboratory scientists model molecular movement within narrow channels of mesoporous nanoparticles October 21st, 2014

Detecting Cancer Earlier is Goal of Rutgers-Developed Medical Imaging Technology: Rare earth nanocrystals and infrared light can reveal small cancerous tumors and cardiovascular lesions October 21st, 2014

Nitrogen Doped Graphene Characterized by Iranian, Russian, German Scientists October 21st, 2014

Nanobiotechnology

Crystallizing the DNA nanotechnology dream: Scientists have designed the first large DNA crystals with precisely prescribed depths and complex 3D features, which could create revolutionary nanodevices October 20th, 2014

Scientists Map Key Moment in Assembly of DNA-Splitting Molecular Machine: Crucial steps and surprising structures revealed in the genesis of the enzyme that divides the DNA double helix during cell replication October 15th, 2014

DNA nano-foundries cast custom-shaped metal nanoparticles: DNA's programmable assembly is leveraged to form precise 3D nanomaterials for disease detection, environmental testing, electronics and beyond October 10th, 2014

Charged graphene gives DNA a stage to perform molecular gymnastics October 9th, 2014

Quantum nanoscience

NIST quantum probe enhances electric field measurements October 8th, 2014

Quantum environmentalism: Putting a qubit's surroundings to good use October 2nd, 2014

Rice launches Center for Quantum Materials: RCQM will immerse global visitors in cross-disciplinary research September 30th, 2014

Big Results Require Big Ambitions: Three young UCSB faculty receive CAREER awards from the National Science Foundation September 18th, 2014

NanoNews-Digest
The latest news from around the world, FREE





  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE