Video Experimental Relacionado

Updated: Jan 29, 2026

Extracting DNA from the Gut Microbes of the Termite Zootermopsis Angusticollis and Visualizing Gut Microbes

Extracting DNA from the Gut Microbes of the Termite Zootermopsis Angusticollis and Visualizing Gut Microbes

Published on: May 28, 2007

La genotoxina bacteriana colibactina humana alquila el ADN

Matthew R Wilson¹, Yindi Jiang¹, Peter W Villalta²

¹Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA.

Science (New York, N.Y.)

|February 16, 2019

Resumen

Ciertas bacterias intestinales producen colibactina, una genotoxina relacionada con el cáncer colorrectal. Los investigadores identificaron su mecanismo de daño al ADN, revelando una estructura inusual de ciclopropano y un potencial biomarcador para la exposición.

Área de la Ciencia:

Microbiología
La genética
Investigación del cáncer

Sus antecedentes:

Ciertas cepas de Escherichia coli producen colibactina, una genotoxina implicada en el cáncer colorrectal.
La estructura química y el mecanismo genotóxico de la colibactina han permanecido elusivo durante más de una década.

Objetivo del estudio:

Para aclarar la estructura química de la colibactina.
Identificar el mecanismo molecular de la genotoxicidad de la colibactina.
Investigar el papel de la colibactina en la patogénesis del cáncer colorrectal.

Principales métodos:

El enfoque de la aductomía del ADN no dirigido.
Síntesis química para la caracterización.
Análisis de líneas celulares humanas y modelos de ratones colonizados con E. coli.

Principales resultados:

Se identificó una modificación covalente del ADN causada por la colibactina.
Se estableció que la colibactina alquila el ADN a través de un ciclopropano electrófilo.
Se ha demostrado la formación de metabolitos de colibactina en ratones y se ha propuesto un adducto intermedio inestable.

Conclusiones:

El mecanismo genotóxico de Colibactin incluye un ADN alquilante electrófilo de ciclopropano inusual.
Los hallazgos proporcionan información mecanicista sobre la carcinogénesis colorrectal inducida por microbios intestinales.
Se identificó un biomarcador potencial para la exposición a la colibactina.

Más Videos Relacionados

Identification of Metabolically Active Bacteria in the Gut of the Generalist Spodoptera littoralis via DNA Stable Isotope Probing Using 13C-Glucose

Identification of Metabolically Active Bacteria in the Gut of the Generalist Spodoptera littoralis via DNA Stable Isotope Probing Using 13C-Glucose

Published on: November 13, 2013

A Gut-on-a-Chip Model to Study the Gut Microbiome-Nervous System Axis

A Gut-on-a-Chip Model to Study the Gut Microbiome-Nervous System Axis

Published on: July 28, 2023

Videos de Conceptos Relacionados

Alkyl Halides

Alkyl Halides

Structural Properties
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...

Bacterial Transformation

Bacterial Transformation

In 1928, bacteriologist Frederick Griffith worked on a vaccine for pneumonia, which is caused by Streptococcus pneumoniae bacteria. Griffith studied two pneumonia strains in mice: one pathogenic and one non-pathogenic. Only the pathogenic strain killed host mice.
Griffith made an unexpected discovery when he killed the pathogenic strain and mixed its remains with the live, non-pathogenic strain. Not only did the mixture kill host mice, but it also contained living pathogenic bacteria that...

Preparation of Alkynes: Alkylation Reaction

Preparation of Alkynes: Alkylation Reaction

Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.

Recombinant DNA

Recombinant DNA

Complementary DNA

Complementary DNA

Mass Spectrometry: Alkyl Halide Fragmentation

Mass Spectrometry: Alkyl Halide Fragmentation

Chlorine isotopes exist as 35Cl and 37Cl in a 3:1 ratio, while bromine isotopes exist as 79Br and 81Br in a 1:1 ratio. The mass spectrum of alkyl halides typically produces two distinct molecular ion peaks, the molecular ion peak, [M], and the molecular ion plus two, [M + 2] peak. The relative heights of these two peaks are proportional to the isotopic abundance ratios of the halide. For example, 2‐chloropropane and 1‐bromopropane display two peaks with relative peak heights in a 3:1 and...