Video Experimental Relacionado
Updated: Jan 25, 2026
08:47
Synthesis and Bioconjugation of Thiol-Reactive Reagents for the Creation of Site-Selectively Modified Immunoconjugates
Published on: March 6, 2019
10.0K
Reactivos bioinspirados de tiofosforodicloruro para la bioconjugación quimioselectiva de histidina
Shang Jia1, Dan He1, Christopher J Chang1,2,3
1Department of Chemistry , University of California , Berkeley , California 94720 , United States.
Journal of the American Chemical Society
|April 25, 2019
Resumen
Los investigadores desarrollaron un nuevo método para modificar los residuos de histidina en las proteínas, lo que permite la funcionalización dirigida. Esta estrategia de modificación de la histidina mejora la entrega de proteínas a las células mediante la unión de moléculas de carga específicas.
Área de la Ciencia:
- La bioquímica
- Biología Química
- Ingeniería de proteínas
Sus antecedentes:
- La bioconjugación selectiva del sitio es crucial para la funcionalidad de las proteínas.
- Los residuos de cisteína y lisina son tradicionalmente el objetivo debido a su nucleofilicidad.
- Existe la necesidad de una modificación selectiva de otros residuos de aminoácidos como la histidina.
Objetivo del estudio:
- Desarrollar una nueva estrategia para la modificación selectiva del sitio de los residuos de histidina en las proteínas.
- Para permitir la funcionalización de proteínas en condiciones suaves utilizando la química dirigida por histidina.
- Explorar la utilidad de la modificación de la histidina para la ingeniería de proteínas y aplicaciones celulares.
Principales métodos:
- Se utilizaron reactivos de tiofosforodicloruro para imitar la fosforilación de la histidina.
- Se utiliza la cicloadición de alquina-azida asistida por cobre (CuAAC) para la fijación de la carga útil.
- Se ha demostrado la modificación selectiva de los residuos de histidina, incluidos los de las etiquetas His.
Principales resultados:
- Se ha logrado un etiquetado rápido y selectivo de las histidinas proteicas en condiciones suaves.
- Introdujo con éxito varias cargas útiles a través de la química CuAAC.
- Mostró una modificación covalente efectiva de las etiquetas His para la purificación y la funcionalidad de las proteínas.
- Se ha demostrado una mayor absorción celular de proteínas a través de la fijación de carga de poliarginina.
Conclusiones:
- Desarrolló una estrategia versátil de modificación de la histidina utilizando nuevos reactivos de tiofosforodicloruro.
- Este método permite la funcionalización de proteínas específicas del sitio y la entrega de carga útil.
- La química dirigida por histidina ofrece nuevas vías para sondear y mejorar la función de las proteínas, particularmente para aplicaciones celulares.
Videos de Conceptos Relacionados
01:26EDTA: Auxiliary Complexing Reagents
1.3K
EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...
1.3K
01:14Acid Halides to Ketones: Gilman Reagent
4.0K
Lithium dialkyl cuprate, also known as Gilman reagents, selectively reduces acid halides to ketones. The acid chloride is treated with Gilman reagent at −78 °C in the presence of ether solution to produce a ketone in good yield.
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
4.0K
01:13Preparation of Carboxylic Acids: Carboxylation of Grignard Reagents
6.0K
Carboxylic acids can be prepared by the carboxylation of Grignard reagents (RMgX). This method is convenient for converting alkyl (primary, secondary or tertiary), vinyl, benzyl, and aryl halides to carboxylic acids with one additional carbon than the starting RMgX.
6.0K
02:42Eukaryotic Transcription Activators
12.6K
Transcription activators are proteins that promote the transcription of genes from DNA to RNA. In most cases, these proteins contain two separate domains ‒ a domain that binds to DNA and a domain for activating transcription; however, in some cases, a single domain is responsible for both binding and activation of transcription, as seen in the glucocorticoid receptor and MyoD.
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These...
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These...
12.6K
03:42Amino acids
104.8K
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
104.8K
03:46Qualitative Analysis
23.8K
For solutions containing mixtures of different cations, the identity of each cation can be determined by qualitative analysis. This technique involves a series of selective precipitations with different chemical reagents, each reaction producing a characteristic precipitate for a specific group of cations. Metal ions within a group are further separated by varying the pH, heating the mixture to redissolve a precipitate, or adding other reagents to form complex ions.
For instance, group IV...
For instance, group IV...
23.8K