Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Infrared sheds light on single protein complexes

Abstract:
Proteins are basic building blocks of life. The chemistry and structure of proteins are essential for their biological function. Indeed, the structure of proteins determines their mechanical and catalytic properties (e.g. enzymes). Such functions literally shape all living beings. Furthermore, the protein structure also plays a major role in many diseases. For example, the secondary structure of a protein (whether it has helical (alpha-) or sheet-like (beta-) internal substructures) is highly relevant in the pathogenous mechanism leading to Alzheimer, Parkinson, and other neuro-degenerative diseases. Although a variety of methods have been developed to study the protein chemistry and structure, recognizing and mapping the secondary structure on the nanometer scale, or even with single protein sensitivity, is still a major challenge. A new infrared spectroscopy technique, called nano-FTIR, has now enabled nanoscale chemical imaging and probing of protein's secondary structure with enormous sensitivity.

Infrared sheds light on single protein complexes

Usurbil, Spain | Posted on December 17th, 2013

nano-FTIR is an optical technique that combines scattering-type scanning near-field optical microscopy (s-SNOM) and Fourier transform infrared (FTIR) spectroscopy. The latter is a tool often used for studying secondary structure of proteins that, however, does not allow for nanoscale mapping of proteins by itself. In nano-FTIR, a sharp metalized tip is illuminated with a broadband infrared laser beam, and the backscattered light is analyzed with a specially designed Fourier transform spectrometer. With this technique, the researchers could now demonstrate local infrared spectroscopy of proteins with a spatial resolution of less than 30 nm.
"The tip acts as an antenna for infrared light and concentrates it at the very tip apex. The nanofocus at the tip apex can be thus considered as an ultra-small infrared light source. It is so small that it only illuminates an area of about 30x30 nm, which is the scale of large protein complexes", says project leader Rainer Hillenbrand.
In order to demonstrate the versatility of nano-FTIR for nanoscale-resolved protein spectroscopy, the researchers measured infrared spectra of single viruses, ferritin complexes, purple membranes and insulin fibrils. "They all exhibit variations of their secondary structure - describes Iban Amenabar, who performed the nanospectroscopy experiments-; viruses and ferritin are mainly made of alpha-helical structures, while insulin fibrils are mainly made of beta-sheet structures". Simon Poly, the biologist in the team, explains that "in a mixture of insulin fibrils and few viruses, standard FTIR spectroscopy did not reveal the presence of the alpha-helical viruses. By probing the protein nanostructures one by one with nano-FTIR we could clearly identify the virus, that is the alpha-helical structures within the beta-sheet ones".
An important aspect of enormous practical relevance is that the nano-FTIR spectra of proteins match extremely well with conventional FTIR spectra, while the spatial resolution is increased by more than 100. "We could measure infrared spectra of even single ferritin particles. These are protein complexes of only 24 proteins. The mass of one ferritin complex is extremely small, only 1 attogram, but we could clearly recognize its alpha-helical structure", says Amenabar.
The researchers also studied single insulin fibrils, which are a model system for neurodegenerative diseases. It is known that insulin fibrils have a core of beta-sheet structure but their complete structure is still not fully clarified. "In nano-FTIR spectra of individual fibrils we recognized not only beta-sheet structure, but also alpha-helical structures, which might be of relevance for fibril association," says Alexander Bittner, leader of the Self-Assembly Group at nanoGUNE.
"We are excited about the novel possibilities that nano-FTIR offers. With sharper tips and improved antenna function, we also hope to obtain infrared spectra of single proteins in the future. We see manifold applications, such as studies of conformational changes in amyloid structures on the molecular level, the mapping of nanoscale protein modifications in biomedical tissue or the label-free mapping of membrane proteins. This could lead to a new era in infrared nano-bio-spectroscopy", concludes Rainer Hillenbrand, head of the Nanooptics Group at nanoGUNE.

####

For more information, please click here

Contacts:
Irati Kortabitarte

34-943-363-040

Itziar Otegui
CIC nanoGUNE
Contact details:

+34 943 574 024

Copyright © Elhuyar Fundazioa

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

Quantum memory with record-breaking capacity based on laser-cooled atoms December 15th, 2017

Record high photoconductivity for new metal-organic framework material December 15th, 2017

Error-free into the quantum computer age December 15th, 2017

Leti Will Demonstrate First 3D Anti-Crash Solution for Embedding in Drones: Fitted on a Mass-Market Microcontroller, 360Fusion Software Technology Detects any Dynamic Obstacle and Helps Guide Drones Away from Collisions December 15th, 2017

Imaging

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

JPK Instruments announce partnership with Swiss company, Cytosurge AG. The partnership makes Cytosurge’s FluidFM® technology available on the JPK NanoWizard® AFM platform December 8th, 2017

Researchers advance technique to detect ovarian cancer: Rice, MD Anderson use fluorescent carbon nanotube probes to achieve first in vivo success November 30th, 2017

Deben reports on a new publication from scientists at La Trobe University in Australia where their CT500 stage is used in micro scanning tomography experiments to better understand ceramic matrix composites under load November 29th, 2017

Nanomedicine

Synthetic protein packages its own genetic material and evolves computationally designed protein assemblies are advancing research in synthetic life and in targeted drug delivery December 15th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Leti to Demo Wristband with Embedded Sensors to Diagnose Sleep Apnea: APNEAband, Which Will Be Demonstrated at CES 2018, Also Monitors Mountain Sickness, Dehydration, Dialysis Treatment Response and Epileptic Seizures December 12th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Discoveries

Quantum memory with record-breaking capacity based on laser-cooled atoms December 15th, 2017

Record high photoconductivity for new metal-organic framework material December 15th, 2017

Error-free into the quantum computer age December 15th, 2017

Synthetic protein packages its own genetic material and evolves computationally designed protein assemblies are advancing research in synthetic life and in targeted drug delivery December 15th, 2017

Announcements

Quantum memory with record-breaking capacity based on laser-cooled atoms December 15th, 2017

Record high photoconductivity for new metal-organic framework material December 15th, 2017

Error-free into the quantum computer age December 15th, 2017

Leti Will Demonstrate First 3D Anti-Crash Solution for Embedding in Drones: Fitted on a Mass-Market Microcontroller, 360Fusion Software Technology Detects any Dynamic Obstacle and Helps Guide Drones Away from Collisions December 15th, 2017

Tools

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

JPK Instruments announce partnership with Swiss company, Cytosurge AG. The partnership makes Cytosurge’s FluidFM® technology available on the JPK NanoWizard® AFM platform December 8th, 2017

Researchers advance technique to detect ovarian cancer: Rice, MD Anderson use fluorescent carbon nanotube probes to achieve first in vivo success November 30th, 2017

Nanobiotechnology

Synthetic protein packages its own genetic material and evolves computationally designed protein assemblies are advancing research in synthetic life and in targeted drug delivery December 15th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Arrowhead Presents New Clinical Data Demonstrating a Sustained Host Response in Hepatitis B Patients Following RNAi Therapy — Up to 5.0 log10 reduction in HBsAg observed; data presented at HEP DART 2017 — December 6th, 2017

Going swimmingly: Biotemplates breakthrough paves way for cheaper nanobots: By using bacterial flagella as a template for silica, researchers have demonstrated an easier way to make propulsion systems for nanoscale swimming robots November 30th, 2017

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