Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Scientists watch as peptides control crystal growth with ‘switches, throttles and brakes’

Aspartic acid-rich peptides adsorbed on a calcium oxalate monohydrate (COM) crystal surface. Models of a peptide and COM crystal structure are overlain on an AFM image collected during growth of the [010] face of COM. The rendered AFM image reveals the molecular structure of the crystal surface including individual kink-sites along a single atomic step. The high peaks show the individual oxalate groups and the dimension along the bottom edge of the image is 60 angstroms.
Aspartic acid-rich peptides adsorbed on a calcium oxalate monohydrate (COM) crystal surface. Models of a peptide and COM crystal structure are overlain on an AFM image collected during growth of the [010] face of COM. The rendered AFM image reveals the molecular structure of the crystal surface including individual kink-sites along a single atomic step. The high peaks show the individual oxalate groups and the dimension along the bottom edge of the image is 60 angstroms.

Abstract:
By producing some of the highest resolution images of peptides attaching to mineral surfaces, scientists have a deeper understanding how biomolecules manipulate the growth crystals. This research may lead to a new treatment for kidney stones using biomolecules.

Scientists watch as peptides control crystal growth with ‘switches, throttles and brakes’

Livermore, CA | Posted on November 25th, 2009

The research, which appears in the Nov. 23 online edition of the journal Proceedings of the National Academy of Science, explores how peptides interact with mineral surfaces by accelerating, switching and inhibiting their growth.

The team, made up of researchers from Lawrence Livermore National Laboratory, the Molecular Foundry at Lawrence Berkeley, the University of California, Davis and the University of Alabama, for the first time produced single-molecule resolution images of this peptide-mineral interaction.

Inorganic minerals play an important role in most biological organisms. Bone, teeth, protective shells or the intricate cell walls of marine diatoms are some displays of biomineralization, where living organisms form structures using inorganic material. Some minerals also can have negative effects on an organism such as in kidney and gallstones, which lead to severe suffering and internal damage in humans and other mammals.

Understanding how organisms limit the growth of pathological inorganic minerals is important in developing new treatment strategies. But deciphering the complex pathways that organisms use to create strong and versatile structures from relatively simple materials is no easy feat. To better understand the process, scientists attempt to mimic them in the laboratory.

By improving the resolution power of an Atomic Force Microscope (AFM), the PNAS authors were able to image individual atomic layers of the crystal interacting with small protein fragments, or peptides, as they fell on the surface of the crystal.

"Imaging biomolecules that are weakly attached to a surface, while simultaneously achieving single-molecule resolution, is normally difficult to do without knocking the molecules off," said Raymond Friddle, an LLNL postdoctoral fellow.

But the team improved upon previous methods and achieved unprecedented resolution of the molecular structure of the crystal surface during the dynamic interaction of each growing layer with peptides. "We were able to watch peptides adhere to the surface, temporarily slow down a layer of the growing crystal, and surprisingly ‘hop' to the next level of the crystal surface."

The images also revealed a mechanism that molecules can use to bind to surfaces that would normally repel them. The high resolution images showed that peptides will cluster together on crystal faces that present the same electronic charge. Under certain conditions the peptides would slow down growth, while under other conditions the peptides could speed up growth.

On another face of the crystal, where the peptides were expected to bind strongly, the researchers found instead that the peptides did not attach to the surface unless the crystal growth slowed. The peptides needed to bind in a specific way to the face, which takes more time than a non-specific attachment. As a result, the growing layers of the crystal were able to shed off the peptides as they attempted to bind.

But when the researchers slowed down the crystal growth rate, the peptides collapsed onto the surface so strongly that they completely stopped growth. The researchers proposed that the phenomenon is due to the unique properties of bio-polymers, such as peptides or polyelectrolytes, which fluctuate in solution before resting in a stable configuration on a surface.

"The results of the catastrophic drop in growth by peptides suggest ways that organisms achieve protection against pathological mineralization," said Jim De Yoreo, the project lead and deputy director of research at LBNL's Molecular Foundry. "Once growth is halted, a very high concentration of the mineral will be needed before growth can again reach significant levels."

He said designing polyelectrolyte modifiers in which the charge, size and ability to repel water can be systematically varied would allow researchers to create the equivalent of "switches, throttles and brakes" for directing crystallization.

####

About Lawrence Livermore National Laboratory
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

For more information, please click here

Contacts:
Anne M. Stark
(925) 422-9799

Copyright © Lawrence Livermore National Laboratory

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 News Press

News and information

Raman Whispering Gallery Detects Nanoparticles September 1st, 2014

A new, tunable device for spintronics: An international team of scientists including physicist Jairo Sinova from the University of Mainz realises a tunable spin-charge converter made of GaAs August 29th, 2014

Nanoscale assembly line August 29th, 2014

New Vice President Takes Helm at CNSE CMOST: Catherine Gilbert To Lead CNSE Children’s Museum of Science and Technology Through Expansion And Relocation August 29th, 2014

Possible Futures

Air Force’s 30-year plan seeks 'strategic agility' August 1st, 2014

IBM Announces $3 Billion Research Initiative to Tackle Chip Grand Challenges for Cloud and Big Data Systems: Scientists and engineers to push limits of silicon technology to 7 nanometers and below and create post-silicon future July 10th, 2014

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

Local girl does good March 22nd, 2014

Nanomedicine

Nanoscale assembly line August 29th, 2014

Copper shines as flexible conductor August 29th, 2014

Novel 'butterfly' molecule could build new sensors, photoenergy conversion devices August 28th, 2014

PetLife Comments on CNN Story on Scorpion Venom Health Benefits August 27th, 2014

Announcements

Raman Whispering Gallery Detects Nanoparticles September 1st, 2014

Nanoscale assembly line August 29th, 2014

New analytical technology reveals 'nanomechanical' surface traits August 29th, 2014

New Vice President Takes Helm at CNSE CMOST: Catherine Gilbert To Lead CNSE Children’s Museum of Science and Technology Through Expansion And Relocation August 29th, 2014

Tools

Raman Whispering Gallery Detects Nanoparticles September 1st, 2014

New analytical technology reveals 'nanomechanical' surface traits August 29th, 2014

Ultra-Low Frequency Vibration Isolation Stabilizes Scanning Tunneling Microscopy at UCLA’s Nano-Research Group August 28th, 2014

Measure Both Elastic and Viscous Properties with AFM Using Asylum Research’s Exclusive AM-FM Viscoelastic Mapping Mode August 28th, 2014

Nanobiotechnology

Nanoscale assembly line August 29th, 2014

The channel that relaxes DNA: Relaxing DNA strands by using nano-channels: Instructions for use August 20th, 2014

Сalculations with Nanoscale Smart Particles August 19th, 2014

Interaction between Drug, DNA for Designing Anticancer Drugs Studied in Iran August 17th, 2014

Alliances/Partnerships/Distributorships

Leading European communications companies and research organizations have launched an EU project developing the future 5th Generation cellular mobile networks August 28th, 2014

JPK expands availability of instrumentation in the USA – appointing new distributors – launched a new web site to support the US market - AFM now available to US users August 26th, 2014

Sunblock poses potential hazard to sea life August 20th, 2014

SouthWest NanoTechnologies Appoints Matteson-Ridolfi for U.S. Distribution of its SMW™ Specialty Multiwall Carbon Nanotubes August 13th, 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