Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Protein Folding01:25

Protein Folding

Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Folding01:22

Protein Folding

Overview
Protein Folding01:22

Protein Folding

Overview
Protein Folding Quality Check in the RER01:29

Protein Folding Quality Check in the RER

ER is the primary site for the maturation and folding of soluble and transmembrane secretory proteins. The calnexin cycle is a specific chaperone system that folds and assesses the confirmation of N-glycosylated proteins before they can exit the ER lumen. The primary players of this quality check pipeline are the lectins, ER-resident chaperones, and a glucosyl transferase enzyme. In case the calnexin system in the lumen fails to salvage a misfolded protein, it is transported to the cytoplasm...
Amyloid Fibrils03:03

Amyloid Fibrils

Amyloid fibrils are aggregates of misfolded proteins.  Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils. 
Amyloid deposits were observed as early as 1639 in the liver and the spleen.   In 1854, Rudolph Virchow performed iodine staining, normally used to...
Protein Organization01:13

Protein Organization

Overview

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Forces behind N- and C-capping of peptidic helices.

Chemical communications (Cambridge, England)·2026
Same author

Temperature-jump QCL spectroscopy of peptide dynamics: expanding spectral accessibility by dual-combs.

Chemical communications (Cambridge, England)·2025
Same author

Arabidopsis CaLB1 undergoes phase separation with the ESCRT protein ALIX and modulates autophagosome maturation.

Nature communications·2024
Same author

Membrane-specific and calcium-dependent binding of the Arabidopsis C2 domain protein CaLB revealed by ATR-FTIR spectroscopy.

Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy·2023
Same author

Calcium-induced compaction and clustering of vesicles tracked with molecular resolution.

Biophysical journal·2023
Same author

Mid-IR quantum cascade laser spectroscopy to resolve lipid dynamics during the photocycle of bacteriorhodopsin.

The Journal of chemical physics·2023

Related Experiment Video

Updated: Jun 4, 2026

Monitoring Protein Aggregation Kinetics In Vivo using Automated Inclusion Counting in Caenorhabditis elegans
06:49

Monitoring Protein Aggregation Kinetics In Vivo using Automated Inclusion Counting in Caenorhabditis elegans

Published on: December 17, 2021

Stability and folding dynamics of polyglutamic acid.

Carsten Krejtschi1, Karin Hauser

  • 1Institute of Biophysics, Goethe-University Frankfurt, Germany.

European Biophysics Journal : EBJ
|January 29, 2011
PubMed
Summary

Polyglutamic acid (PGA) exhibits reversible helix-coil transitions in aqueous solutions, with stability dependent on solution pH. This study combines spectroscopy to analyze PGA

Area of Science:

  • Biophysical Chemistry
  • Protein Dynamics
  • Spectroscopy

Background:

  • Polyglutamic acid (PGA) is an alpha-helical peptide in aqueous solution.
  • PGA serves as an ideal model for studying helix-coil transitions.
  • Understanding peptide stability and folding is crucial in biochemistry.

Purpose of the Study:

  • To investigate the thermal stability and folding dynamics of polyglutamic acid.
  • To characterize the reversible helix-coil transition of PGA using spectroscopy.
  • To analyze the folding mechanisms of PGA based on equilibrium and time-resolved data.

Main Methods:

  • Equilibrium circular dichroism (CD) spectroscopy.
  • Fourier-transform infrared (FTIR) spectroscopy.
  • Time-resolved temperature-jump infrared (IR) spectroscopy.

More Related Videos

Thermodynamics of Membrane Protein Folding Measured by Fluorescence Spectroscopy
10:09

Thermodynamics of Membrane Protein Folding Measured by Fluorescence Spectroscopy

Published on: April 28, 2011

Microfluidic Mixers for Studying Protein Folding
12:42

Microfluidic Mixers for Studying Protein Folding

Published on: April 10, 2012

Related Experiment Videos

Last Updated: Jun 4, 2026

Monitoring Protein Aggregation Kinetics In Vivo using Automated Inclusion Counting in Caenorhabditis elegans
06:49

Monitoring Protein Aggregation Kinetics In Vivo using Automated Inclusion Counting in Caenorhabditis elegans

Published on: December 17, 2021

Thermodynamics of Membrane Protein Folding Measured by Fluorescence Spectroscopy
10:09

Thermodynamics of Membrane Protein Folding Measured by Fluorescence Spectroscopy

Published on: April 28, 2011

Microfluidic Mixers for Studying Protein Folding
12:42

Microfluidic Mixers for Studying Protein Folding

Published on: April 10, 2012

Main Results:

  • PGA exhibits reversible unfolding and refolding at pD > 5.
  • A helix-coil transition occurs at pD 5.4 with a melting temperature (T(m)) of 307 K.
  • Folding and unfolding rates and activation energies were determined using a two-state model.

Conclusions:

  • Combined spectroscopic data provide a comprehensive characterization of PGA's structural transition.
  • The study elucidates the folding mechanisms of polyglutamic acid.
  • PGA's thermal stability and folding dynamics are pH-dependent.