Video Experimental Relacionado

Updated: Jul 8, 2026

EPR Monitored Redox Titration of the Cofactors of Saccharomyces cerevisiae Nar1

EPR Monitored Redox Titration of the Cofactors of Saccharomyces cerevisiae Nar1

Published on: November 26, 2014

La regulación redox de la proteína tirosina fosfatasa 1B incluye un intermediario sulfenilo-amida

Annette Salmeen¹, Jannik N Andersen, Michael P Myers

¹Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK.

|June 13, 2003

Resumen

El peróxido de hidrógeno regula la señalización celular mediante la inhibición reversible de la proteína tirosina fosfatasa 1B (PTP1B). Una nueva modificación de sulfenil-amida protege PTP1B y permite el control redox de esta enzima crítica.

Área de la Ciencia:

La bioquímica es la bioquímica.
La señalización celular de las células.
Enzimología Enzimología.

Sus antecedentes:

El peróxido de hidrógeno (H2O2) es un segundo mensajero crucial en la transducción de señales celulares.
El H2O2 regula las vías que involucran a las proteínas tirosina quinasas y fosfatasas.
Las fosfatasas de proteína tirosina (PTP) son reguladores clave de los procesos celulares, a menudo inhibidos por la oxidación mediada por H2O2.

Objetivo del estudio:

Para analizar estructuralmente la regulación redox-dependiente de la proteína tirosina fosfatasa 1B (PTP1B).
Comprender el mecanismo de la inhibición de PTP1B por el estrés oxidativo.
Para aclarar el papel de las nuevas modificaciones oxidativas en la actividad de PTP1B.

Principales métodos:

Análisis estructural de PTP1B bajo condiciones oxidativas.
Investigación de la oxidación de PTP1B después de la estimulación con insulina y factor de crecimiento epidérmico.
Caracterización de estados intermedios de oxidación y cambios conformacionales.

Principales resultados:

PTP1B es reversiblemente inhibido por la oxidación, formando un intermediario del ácido sulfénico.
Este intermedio se convierte rápidamente en una nueva especie de sulfenil-amida.
La oxidación induce cambios conformacionales significativos en el sitio catalítico de PTP1B, inhibiendo la unión al sustrato.

Conclusiones:

La modificación de la sulfenil-amida protege la cisteína del sitio activo de PTP1B de una oxidación irreversible.
Esta modificación permite la regulación redox reversible de la actividad de PTP1B por los tiolos.
Las ideas estructurales revelan un nuevo mecanismo para controlar la función de PTP1B en la señalización celular.

Más Videos Relacionados

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Published on: June 7, 2018

Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation

Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation

Published on: June 21, 2021

Videos de Conceptos Relacionados

Oxidation-Reduction Reactions

Oxidation-Reduction Reactions

Oxidation–Reduction Reactions

Oxidation of Alcohols

Oxidation of Alcohols

In this lesson, the oxidation of alcohols is discussed in depth. The various reagents used for oxidation of primary and secondary alcohols are detailed, and their mechanism of action is provided.
The process of oxidation in a chemical reaction is observed in any of the three forms:

Protein Modifications in the RER

Protein Modifications in the RER

Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.

Oxidation and Reduction of Organic Molecules

Oxidation and Reduction of Organic Molecules

Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions, which occur at the same time. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called redox reactions.
The removal of an electron from a molecule, results in a...

Electron Transport Chain: Complex III and IV

Electron Transport Chain: Complex III and IV

During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...

Sulfur Assimilation

Sulfur Assimilation

Sulfur is an essential element in biological systems, contributing to synthesizing key biomolecules, including amino acids such as cysteine and methionine, and cofactors such as coenzyme A and biotin. Microorganisms primarily assimilate sulfur as sulfate (SO₄²⁻) from the environment, which must undergo a series of biochemical transformations before it can be incorporated into cellular components. As sulfate is highly oxidized, it must undergo assimilatory sulfate reduction to become...