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 Kinases and Phosphatases02:54

Protein Kinases and Phosphatases

Proteins undergo chemical modifications that trigger changes in the charge, structure, and conformation of the proteins. Phosphorylation, acetylation, glycosylation, nitrosylation, ubiquitination, lipidation, methylation, and proteolysis are various protein modifications that regulate protein activity. Such modifications are usually enzyme-driven.
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
Pharmacodynamic Models: Link Model and Systems Pharmacodynamic Model01:14

Pharmacodynamic Models: Link Model and Systems Pharmacodynamic Model

The link model is a fundamental pharmacokinetic-pharmacodynamic (PK–PD) approach to account for delayed drug responses when the observed effect does not immediately correlate with the drug's plasma concentration peak. This delay is mathematically addressed by introducing an effect compartment concentration, Ce, which is kinetically linked to the plasma concentration, Cp, via a first-order rate constant, ke0. The linkage allows for a more accurate prediction of drug effects over time. A higher...
Enzymes02:34

Enzymes

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...
Pharmacodynamic Models: Overview01:27

Pharmacodynamic Models: Overview

Pharmacodynamic (PD) responses describe the interaction between a drug and its biological target, culminating in a physiological effect. These responses can be classified into different types: continuous variables, such as blood glucose levels; categorical outcomes, like survival rates; and time-to-event metrics, such as disease progression. Understanding and modeling PD responses are critical for optimizing drug efficacy and safety.PD models describe the relationship between drug concentration...
Introduction to Mechanisms of Enzyme Catalysis01:13

Introduction to Mechanisms of Enzyme Catalysis

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 a mild...
Induced-fit Model01:13

Induced-fit Model

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 characteristics of...

You might also read

Related Articles

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

Sort by
Same author

Real-world implementation of video-observed therapy in an urban TB program in the United States.

The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease·2021
Same author

spiel ohne grenzen/pou2 is required during establishment of the zebrafish midbrain-hindbrain boundary organizer.

Development (Cambridge, England)·2001
Same author

Kinetic analysis for analyte-receptor binding and dissociation in biosensor applications: a fractal analysis.

Biotechnology & genetic engineering reviews·2001
Same author

A single- and a dual-fractal analysis of antigen-antibody binding kinetics for different biosensor applications.

Biosensors & bioelectronics·2001
Same author

A kinetic study of analyte-receptor binding and dissociation, and dissociation alone, for biosensor applications: a fractal analysis.

Analytical biochemistry·2001
Same author

A single-fractal analysis of cellular analyte-receptor binding kinetics utilizing biosensors.

Bio Systems·2001

Related Experiment Video

Updated: Jul 4, 2026

Detection of the pH-dependent Activity of Escherichia coli Chaperone HdeB In Vitro and In Vivo
08:32

Detection of the pH-dependent Activity of Escherichia coli Chaperone HdeB In Vitro and In Vivo

Published on: October 23, 2016

pH-Dependent enzyme deactivation models.

A Chitnis1, A Sadana

  • 1Chemical Engineering Department, University of Mississippi, University, Mississippi 38677-9740, USA.

Biotechnology and Bioengineering
|September 1, 1989
PubMed
Summary

A new enzyme deactivation model explains how pH affects enzyme activity over time. This model helps determine rate constants and enzyme activities, offering mechanistic insights into enzyme behavior.

Area of Science:

  • Biochemistry
  • Enzyme kinetics
  • Chemical kinetics

Background:

  • Enzyme activity is often influenced by pH.
  • Understanding pH-dependent enzyme deactivation is crucial for various biochemical processes.
  • Existing models may not fully capture the complexities of pH-mediated enzyme inactivation.

Purpose of the Study:

  • To present a novel "series-type" enzyme deactivation model.
  • To elucidate the pH dependence of enzyme inactivation kinetics.
  • To provide mechanistic insights into enzyme deactivation processes.

Main Methods:

  • Developed a pH-dependent enzyme deactivation model incorporating rapid protonation/deprotonation equilibria and slower inactivation rates.
  • Analyzed enzyme activity-time trajectories at various pH levels.

More Related Videos

Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry
13:26

Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry

Published on: September 13, 2014

Enzymatic Modification and Flow Cytometry Assessment of Yeast Surface Displayed Proteins
10:54

Enzymatic Modification and Flow Cytometry Assessment of Yeast Surface Displayed Proteins

Published on: May 30, 2025

Related Experiment Videos

Last Updated: Jul 4, 2026

Detection of the pH-dependent Activity of Escherichia coli Chaperone HdeB In Vitro and In Vivo
08:32

Detection of the pH-dependent Activity of Escherichia coli Chaperone HdeB In Vitro and In Vivo

Published on: October 23, 2016

Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry
13:26

Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry

Published on: September 13, 2014

Enzymatic Modification and Flow Cytometry Assessment of Yeast Surface Displayed Proteins
10:54

Enzymatic Modification and Flow Cytometry Assessment of Yeast Surface Displayed Proteins

Published on: May 30, 2025

  • Applied the model to three literature examples of pH-dependent enzyme deactivations.

    • Main Results:

    • The model successfully evaluated protonation and inactivation rate constants.
    • Specific activities of different enzyme forms were determined.
    • Demonstrated general applicability and consistency with experimental data for diverse enzymes.

    Conclusions:

    • The proposed model offers a mechanistic understanding of pH-dependent enzyme deactivation.
    • It accurately describes enzyme activity changes over time across different pH values.
    • The model provides valuable tools for analyzing enzyme kinetics and stability.