Video Experimental Relacionado

Updated: Sep 19, 2025

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Published on: December 16, 2013

Guías de secuencia de reconocimiento de péptidos Enlace cruzado de la cadena lateral catalítica de péptidos vegetales

Stella T Lima¹, Michael A Pasquale¹, M Rafiul O K Noyon¹

¹Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States.

Journal of the American Chemical Society

|June 5, 2025

Resumen

Las enzimas vegetales dependientes del cobre, las ciclas de péptidos de dominio BURP (BpC), catalizan el enlace cruzado de aminoácidos desafiante. Este estudio revela su mecanismo catalítico y su amplia aplicabilidad en la biosíntesis de productos naturales.

Área de la Ciencia:

La bioquímica
Enzimología
Biosíntesis de productos naturales

Sus antecedentes:

El enlace cruzado de la cadena lateral de aminoácidos es una reacción enzimática oxidativa generalmente mediada por enzimas de clúster hemo o hierro-azufre.
Las ciclas de péptidos del dominio BURP de las plantas (BpC) representan una clase recién descubierta de enzimas dependientes del cobre capaces de reacciones de enlace cruzado similares.
ArbB2, un BpC, forma un enlace de Tyr-fenol-O con Leu-Cβ en la arabipeptina A, un alcaloide ciclopéptido de *Coffea arabica*.

Objetivo del estudio:

Investigar el mecanismo catalítico de las ciclas de péptidos de dominio BURP dependientes del cobre (BpC).
Para permitir estudios cuantitativos de la actividad de BpC utilizando sustratos peptídicos mínimos.
Explorar el alcance del sustrato y la aplicabilidad de los BpC en la biosíntesis de alcaloides ciclopéptidos.

Principales métodos:

Desarrollo de sustratos péptidos mínimos para estudios cuantitativos de ArbB2.
Análisis de la dependencia del reductor y del oxígeno para lograr la rotación catalítica.
Análisis cinético, mutacional, del alcance del sustrato y del procesamiento multicorazón.

Principales resultados:

Se logró por primera vez la rotación catalítica para la familia de péptidos ciclasa de dominio BURP (BpC).
Se estableció la dependencia del oxígeno y se confirmó la ausencia de peróxido de hidrógeno como producto secundario.
Se demostró que los hallazgos son aplicables a múltiples BpC involucrados en la biosíntesis de alcaloides ciclopéptidos.

Conclusiones:

Proporciona información fundamental sobre una nueva y extendida familia de ciclas de péptidos dependientes del cobre.
Establece las bases para futuras investigaciones mecanicistas de las enzimas BpC.
Destaca el papel de las BpC en la biosíntesis de productos naturales vegetales como los alcaloides ciclopéptidos.

Más Videos Relacionados

Quantifying the Binding Interactions Between CuII and Peptide Residues in the Presence and Absence of Chromophores

Quantifying the Binding Interactions Between CuII and Peptide Residues in the Presence and Absence of Chromophores

Published on: April 5, 2022

Construction of Cyclic Cell-Penetrating Peptides for Enhanced Penetration of Biological Barriers

Construction of Cyclic Cell-Penetrating Peptides for Enhanced Penetration of Biological Barriers

Published on: September 19, 2022

Videos de Conceptos Relacionados

Cell Signaling in Plants

Cell Signaling in Plants

Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...

Peptide Bonds

Peptide Bonds

A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...

C4 Pathway and CAM

C4 Pathway and CAM

Most plants use the C3 pathway for carbon fixation. However, some plants, such as sugar cane, corn, and cacti that grow in hot conditions, use alternative pathways to fix carbon and conserve energy loss due to photorespiration. Photorespiration is the process that occurs when the oxygen concentration is high. Under such conditions, the rubisco enzyme in the Calvin cycle binds O2 instead of CO2, which halts photosynthesis and consumes energy.
C4 Pathway
The C4 pathway is used by plants such as...

Allosteric Proteins-ATCase

Allosteric Proteins-ATCase

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...

Translocation of Proteins into the Mitochondria

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...

Protein Transport to the Thylakoids

Protein Transport to the Thylakoids

Thylakoids are membrane-bound sac-like structures within the chloroplast that serve as sites for photosynthesis. Thylakoid lumen contains many electron transport proteins and is enclosed by a thylakoid membrane rich in the light-harvesting complex. Proteins targeted to the thylakoids are transported as precursors and are sorted by the general TOC/TIC import pathway. Once the precursor reaches the stroma, stromal processing peptidases remove their transit signal and expose thylakoid signal...