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

Amides to Carboxylic Acids: Hydrolysis01:28

Amides to Carboxylic Acids: Hydrolysis

Amides can undergo either acid-catalyzed hydrolysis or base-promoted hydrolysis through a typical nucleophilic acyl substitution. Each hydrolysis requires severe conditions.
Acid-catalyzed hydrolysis:
Hydrolysis of amides under acidic conditions yields carboxylic acids. Since the reaction occurs slowly, hydrolysis requires the conditions of heat.
The mechanism begins with the protonation of the carbonyl oxygen by the acid catalyst. The protonation makes the amide carbonyl carbon more...
Basicity of Aliphatic Amines01:21

Basicity of Aliphatic Amines

Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
Hydrogen Bonds01:04

Hydrogen Bonds

A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
Hydrogen Bonds00:26

Hydrogen Bonds

Hydrogen BondsHydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.Hydrogen Bonds Control the World!Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are...
Weak Base Solutions03:21

Weak Base Solutions

Some compounds produce hydroxide ions when dissolved by chemically reacting with water molecules. In all cases, these compounds react only partially and so are classified as weak bases. These types of compounds are also abundant in nature and important commodities in various technologies. For example, global production of the weak base ammonia is typically well over 100 metric tons annually, being widely used as an agricultural fertilizer, a raw material for chemical synthesis of other...
Basicity of Heterocyclic Aromatic Amines01:25

Basicity of Heterocyclic Aromatic Amines

Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).

You might also read

Related Articles

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

Sort by
Same author

In silico design and validation of high-affinity RNA aptamers for SARS-CoV-2 comparable to neutralizing antibodies.

eLife·2026
Same author

Nonaqueous Ion Transport through Nanopores: A Nonlinear Behavior Driven by Enhanced Ion Correlation.

Journal of the American Chemical Society·2026
Same author

A hypomorphic mutation in the boron transporter OsBOR1 sensitizes rice panicle development to combined stress of boron deficiency and low temperature.

Plant physiology and biochemistry : PPB·2026
Same author

Structural studies of an antinecroptosis viral:human functional heteroamyloid M45:RIPK3 using SSNMR.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Leveraging a naturally occurring IgM autoantibody to target diabetogenic T cells: a precision medicine approach to type 1 diabetes.

Journal of immunology (Baltimore, Md. : 1950)·2026
Same author

Bile Canalicular Bitter Taste Receptors Inhibit β-Adrenergic Receptor-Induced Lipolysis in Steatotic Hepatocytes.

International journal of molecular sciences·2026

Related Experiment Video

Updated: Jun 26, 2026

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
13:00

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions

Published on: April 4, 2014

Urea's action on hydrophobic interactions.

Ronen Zangi1, Ruhong Zhou, B J Berne

  • 1Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.

Journal of the American Chemical Society
|January 7, 2009
PubMed
Summary

Urea (a protein denaturant) unfolds hydrophobic chains by weakening interactions, acting like a surfactant. This direct binding mechanism, driven by stronger dispersion interactions than water, explains its protein-denaturing capabilities.

More Related Videos

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors
10:33

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors

Published on: October 26, 2015

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
06:44

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups

Published on: April 6, 2017

Related Experiment Videos

Last Updated: Jun 26, 2026

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
13:00

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions

Published on: April 4, 2014

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors
10:33

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors

Published on: October 26, 2015

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
06:44

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups

Published on: April 6, 2017

Area of Science:

  • Biochemistry
  • Physical Chemistry
  • Computational Chemistry

Background:

  • Urea has been used for over a century to denature proteins.
  • The precise mechanism of urea's protein-denaturing action remains unclear.

Purpose of the Study:

  • To elucidate the molecular mechanism behind urea's protein-denaturing properties.
  • To investigate the role of hydrophobic interactions and urea's binding.

Main Methods:

  • Molecular dynamics simulations of a purely hydrophobic polymer chain in aqueous urea solutions.
  • Simulations of hydrophobic plates and graphene sheets in urea solutions.
  • Analysis of preferential binding and interaction energies.

Main Results:

  • Urea (7 M) unfolds hydrophobic chains by weakening hydrophobic interactions.
  • Urea directly binds preferentially to hydrophobic surfaces, reducing attraction.
  • Enthalpy drives binding and weakened hydrophobic interactions, scaling with Lennard-Jones energy parameter epsilon(b).

Conclusions:

  • Urea acts as a surfactant, directly binding to hydrophobic regions and weakening their interactions.
  • Stronger attractive dispersion interactions between urea and protein components than water explain urea's denaturing effect.
  • The indirect chaotropic mechanism is unlikely to be the primary cause of urea's denaturation.