Video Experimental Relacionado

Updated: Jul 10, 2026

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids

Published on: May 4, 2018

Adaptación biosintética de la microcina E492m: la modificación post-traduccional proporciona un conjugado

Elizabeth M Nolan¹, Michael A Fischbach, Alexander Koglin

¹Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.

Journal of the American Chemical Society

|November 2, 2007

Resumen

Cuatro proteínas modifican la microcina E492 (MccE492), una toxina de la Klebsiella pneumoniae. Se adjuntan una enterobactina modificada (recolector de hierro) a MccE492, creando un potente agente antibacteriano.

Área de la Ciencia:

Microbiología Microbiología.
La bioquímica es la bioquímica.
Biología Molecular Biología Molecular

Sus antecedentes:

Klebsiella pneumoniae RYC492 secreta microcina E492 (MccE492), una toxina proteica de 84 residuos dirigida a las bacterias Gram negativas.
MccE492 sufre una extensa modificación post-traduccional para alcanzar su forma madura y activa, MccE492m.

Objetivo del estudio:

Para aclarar los mecanismos moleculares y la maquinaria de proteínas responsables de la modificación post-traducional de MccE492.
Caracterizar los pasos enzimáticos involucrados en la derivación de la enterobactina y su posterior adherencia a MccE492.

Principales métodos:

Análisis genético del grupo de genes MccE492 para identificar proteínas modificadoras (MceCDIJ).
Análisis bioquímicos para determinar las actividades enzimáticas de MceC, MceD, MceI y MceJ.
Caracterización de la enterobactina modificada y su vinculación con MccE492 utilizando técnicas analíticas.

Principales resultados:

El complejo proteico MceCDIJ es responsable de la adaptación post-traducional de MccE492.
Las enzimas MceC y MceD modifican la enterobactina a través de la C-glucosilación e hidrólisis.
El complejo MceI y MceJ une la enterobactina modificada al extremo C de MccE492, formando un enlace de éster glicosílico C6' después de una reorganización no enzimática.

Conclusiones:

Las proteínas MceCDIJ son esenciales para producir la forma madura y tóxica de MccE492.
El estudio revela un nuevo mecanismo para la conjugación de sideróforos con toxinas peptídicas.
Comprender estas modificaciones proporciona información sobre la producción de toxinas bacterianas y los posibles objetivos antimicrobianos.

Más Videos Relacionados

The Logic, Experimental Steps, and Potential of Heterologous Natural Product Biosynthesis Featuring the Complex Antibiotic Erythromycin A Produced Through E. coli

The Logic, Experimental Steps, and Potential of Heterologous Natural Product Biosynthesis Featuring the Complex Antibiotic Erythromycin A Produced Through E. coli

Published on: January 13, 2013

Bacterial Peptide Display for the Selection of Novel Biotinylating Enzymes

Bacterial Peptide Display for the Selection of Novel Biotinylating Enzymes

Published on: October 3, 2019

Videos de Conceptos Relacionados

Inhibitors of Bacterial Protein Synthesis

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...

Bacterial Protein Maturation

Bacterial Protein Maturation

Bacterial protein maturation is a tightly regulated process that ensures newly synthesized polypeptides achieve correct functional conformations. This maturation involves a series of modifications, folding events, and quality control steps, often assisted by specialized chaperone proteins.N-Terminal ModificationsThe maturation of bacterial polypeptides begins cotranslationally as the polypeptide exits the ribosome. The first amino acid, N-formylmethionine (fMet), is typically modified at the...

Production of Pharmaceuticals

Production of Pharmaceuticals

Industrial insulin production uses genetically engineered E. coli expressing a proinsulin gene controlled by a tryptophan promoter and containing a methionine linker for later cleavage. The cells also carry ampicillin resistance for selective growth. Seed cultures are stored at −80 °C and production begins by thawing a small amount to inoculate starter cultures, which are progressively scaled to a 50,000-L bioreactor. In the bioreactor, E. coli grow in nutrient-rich media under sterile, tightly...

Inhibitors of Gram-positive Cell Wall Synthesis

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...