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

Introduction to Mechanisms of Enzyme Catalysis01:13

Introduction to Mechanisms of Enzyme Catalysis

8.3K
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes...
8.3K
Factors Affecting α-Alkylation of Ketones: Choice of Base01:10

Factors Affecting α-Alkylation of Ketones: Choice of Base

3.2K
α-Alkylation of ketones is achieved in the presence of alkyl halides and a base. The reaction proceeds via the formation of an enolate ion followed by nucleophilic substitution. The choice of base employed is essential as it is the key factor in determining the reaction outcome.
The reaction involving bases like EtO− whose conjugate acid EtOH (pKa = 15.9) is stronger than the ketone (pKa = 19.2) results in an equilibrium mixture with higher ketone concentration. As a consequence,...
3.2K
Allosteric Proteins-ATCase01:19

Allosteric Proteins-ATCase

5.8K
Binding sites linkages can regulate a protein's function.  For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to  N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
5.8K
Enzymes02:34

Enzymes

81.7K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
81.7K
Nucleophiles02:30

Nucleophiles

13.6K
The word “nucleophile” has a Greek root and translates to nucleus-loving. Nucleophiles are either negatively charged or neutral species with a pair of electrons in a high-energy occupied molecular orbital (HOMO). As these species tend to donate electron pairs, nucleophiles are considered Lewis bases as well. Negatively charged species, like OH−, Cl−, or HS−, with one or several pairs of electrons, are typically nucleophiles. Similarly, neutral species such as...
13.6K
Induced-fit Model01:13

Induced-fit Model

81.0K
Most chemical reactions in cells require enzymes—biological catalysts that speed up the reaction without being consumed or permanently changed. They reduce the activation energy needed to convert the reactants into products. Enzymes are proteins, that usually work by binding to a substrate—a reactant molecule that they act upon.
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical...
81.0K

You might also read

Related Articles

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

Sort by
Same author

Assessment of Temperature Monitoring Techniques in Neonatal and Juvenile BALB/cJ and C57BL/6J Mice (Mus musculus) as They Age.

Journal of the American Association for Laboratory Animal Science : JAALAS·2026
Same author

Acute Comparative Analysis of Anesthetic Methods in Neonatal Mice (Mus musculus) Using Ultrasonic Vocalizations and Biochemical Markers.

Journal of the American Association for Laboratory Animal Science : JAALAS·2026
Same author

Fatty acid nitroalkenes regulate intestinal lipid absorption.

Journal of lipid research·2025
Same author

Redox Regulation of cAMP-Dependent Protein Kinase and Its Role in Health and Disease.

Life (Basel, Switzerland)·2025
Same author

Associations between metal(loid) exposure with overweight and obesity and abdominal obesity in the general population: A cross-sectional study in China.

Chemosphere·2023
Same author

Investigating the Diagnostic and Therapeutic Potential of SREBF2-Related Lipid Metabolism Genes in Colon Cancer.

OncoTargets and therapy·2023

Related Experiment Video

Updated: Jul 15, 2025

Defining Substrate Specificities for Lipase and Phospholipase Candidates
08:59

Defining Substrate Specificities for Lipase and Phospholipase Candidates

Published on: November 23, 2016

15.0K

Redox Modification of PKA-Cα Differentially Affects Its Substrate Selection.

Jeannette Delva-Wiley1, Ese S Ekhator1, Laquaundra L Adams1

  • 1Department of Biology, North Carolina A&T State University, Greensboro, NC 27411, USA.

Life (Basel, Switzerland)
|September 28, 2023
PubMed
Summary

Redox modification of cyclic AMP-dependent protein kinase alpha (PKA-Cα) alters its substrate specificity. Oxidation impacts PKA-Cα activity differently across various substrates, revealing crosstalk between redox and phosphorylation signaling.

Keywords:
cAMP-dependent protein kinase (PKA)oxidationphosphorylation-dependent signalingprotein kinasereactive oxygen speciesredox signaling

More Related Videos

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
09:42

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes

Published on: January 16, 2016

9.1K
Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach
11:11

Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach

Published on: February 21, 2019

7.4K

Related Experiment Videos

Last Updated: Jul 15, 2025

Defining Substrate Specificities for Lipase and Phospholipase Candidates
08:59

Defining Substrate Specificities for Lipase and Phospholipase Candidates

Published on: November 23, 2016

15.0K
Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
09:42

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes

Published on: January 16, 2016

9.1K
Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach
11:11

Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach

Published on: February 21, 2019

7.4K

Area of Science:

  • Biochemistry
  • Cellular Signaling
  • Enzymology

Background:

  • Cyclic AMP-dependent protein kinase (PKA) regulates crucial cellular processes and is implicated in diseases like diabetes and neurodegeneration.
  • The alpha isoform of the catalytic subunit of PKA (PKA-Cα) undergoes oxidation at C199, located in the active site.
  • The functional impact of PKA-Cα C199 oxidation on substrate selection is largely unknown.

Purpose of the Study:

  • To investigate how redox modification of PKA-Cα at C199 affects its substrate specificity.
  • To explore the differential effects of oxidation on PKA-Cα's kinase activity towards various substrates.
  • To understand the interplay between redox and phosphorylation signaling pathways mediated by PKA.

Main Methods:

  • Biochemical assays including trans-phosphorylation and steady-state kinetics.
  • Biophysical techniques such as surface plasmon resonance and fluorescence polarization.
  • Examined the effects of diamide- and H2O2-induced oxidation on PKA-Cα activity.

Main Results:

  • Redox modification of PKA-Cα differentially impacts its activity towards different substrates.
  • Diamide-mediated oxidation reduced PKA-Cα activity on Kemptide and CREBtide but not Crosstide.
  • H2O2-dependent oxidation initially increased PKA-Cα activity across substrates, with concentration-dependent variations.

Conclusions:

  • Oxidation of PKA-Cα at C199 alters substrate selection, highlighting crosstalk between redox and phosphorylation signaling.
  • Findings provide insights into the role of PKA in integrating redox and phosphorylation signals.
  • The conserved nature of C199 suggests broader implications for AGC kinase family members in redox-dependent signaling.