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

Variables Affecting Phosphorescence and Fluorescence01:26

Variables Affecting Phosphorescence and Fluorescence

Fluorescence and phosphorescence are essential phenomena in fields like analytical chemistry, biological imaging, and materials science, where they detect molecular properties and visualize cellular structures. Understanding the variables that influence these luminescent behaviors is crucial for maximizing accuracy and efficiency in their applications. These variables can broadly be grouped into chemical structure, solvent properties, and external conditions, each playing a distinct role in...
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 Organization01:13

Protein Organization

Overview
Protein Organization01:24

Protein Organization

Proteins are polymers of amino acid residues. They are versatile and responsible for different cellular functions, including DNA replication, molecular transport, catalysis, and structural support. Proteins have a hierarchical structure comprising at least three levels of organization: primary, secondary, and tertiary structure. Some large proteins have a quaternary structure where individual protein subunits are linked together.
The primary structure of a protein is its amino acid sequence.

You might also read

Related Articles

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

Sort by
Same author

Cooperative Substructure and Energetics of Allosteric Regulation of the Catalytic Core of the E3 Ubiquitin Ligase Parkin by Phosphorylated Ubiquitin.

Biomolecules·2024
Same author

Hydrogen production by a fully <i>de novo</i> enzyme.

Dalton transactions (Cambridge, England : 2003)·2024
Same author

Switching the proton-coupled electron transfer mechanism for non-canonical tyrosine residues in a <i>de novo</i> protein.

Chemical science·2024
Same author

Determining the Conformational Stability of a Protein from Urea and Thermal Unfolding Curves.

Current protocols·2023
Same author

Correction to: Protease-stable DARPins as promising oral therapeutics.

Protein engineering, design & selection : PEDS·2022
Same author

Protease-stable DARPins as promising oral therapeutics.

Protein engineering, design & selection : PEDS·2021

Related Experiment Video

Updated: Jul 9, 2026

Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET
12:07

Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET

Published on: October 9, 2021

Peptide sequence and conformation strongly influence tryptophan fluorescence.

Roy W Alston1, Mauricio Lasagna, Gerald R Grimsley

  • 1Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, Texas A&M University, College Station, Texas 77843, USA.

Biophysical Journal
|December 11, 2007
PubMed
Summary

Understanding tryptophan (Trp) fluorescence in peptides is key to studying protein denaturation. Peptide models reveal sequence and conformation impact Trp fluorescence, offering insights into ribonuclease Sa (RNase Sa) behavior.

More Related Videos

Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability
10:31

Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability

Published on: February 3, 2022

PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase
09:31

PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase

Published on: September 26, 2020

Related Experiment Videos

Last Updated: Jul 9, 2026

Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET
12:07

Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET

Published on: October 9, 2021

Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability
10:31

Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability

Published on: February 3, 2022

PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase
09:31

PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase

Published on: September 26, 2020

Area of Science:

  • Biochemistry
  • Biophysics
  • Protein Chemistry

Background:

  • The denatured state ensemble of proteins is crucial for understanding protein folding and function.
  • Tryptophan (Trp) fluorescence is a sensitive probe for monitoring protein structure and dynamics.
  • Interpreting Trp fluorescence in complex proteins like ribonuclease Sa (RNase Sa) requires understanding its behavior in simpler peptide models.

Purpose of the Study:

  • To investigate the fluorescence properties of tryptophan (Trp) in various model peptides.
  • To understand the influence of peptide sequence and conformation on Trp fluorescence.
  • To establish better peptide models for studying Trp residues in proteins, specifically in the context of RNase Sa.

Main Methods:

  • Studied fluorescence emission spectra, fluorescence lifetimes, and fluorescence quenching (using acrylamide and iodide).
  • Examined model peptides including N-acetyl-L-tryptophanamide (NATA), AWA, and six pentapeptides with sequences mimicking RNase Sa.
  • Performed measurements in concentrated solutions of urea and guanidine hydrochloride to mimic denaturing conditions.

Main Results:

  • Fluorescence intensity varied significantly among peptides, with NATA, AWA, and AAWAA showing different quenching efficiencies despite differing numbers of carbonyl groups.
  • The pentapeptide EAWQE exhibited over 50% higher fluorescence intensity than DYWTG, indicating sequence-dependent effects.
  • Peptides, particularly pentapeptides, serve as more accurate models for Trp residues in proteins than the tripeptide NATA.

Conclusions:

  • Peptide sequence and conformation significantly influence tryptophan fluorescence.
  • Model peptides provide valuable insights into Trp fluorescence mechanisms, including excited-state electron transfer to peptide carbonyls.
  • Further research is needed to fully elucidate tryptophan fluorescence, even in simple model systems.