Publication: Identificación y caracterización molecular de mecanismos de adaptación plasmídica a nuevas familias bacterianas
Loading...
Files
Official URL
Full text at PDC
Publication Date
2019-11-26
Authors
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad Complutense de Madrid
Citations
Exportar
Abstract
Durante los últimos años la resistencia a antibióticos está aumentando de forma alarmante, aumento propiciado en gran medida por el mal uso que se ha hecho de estos fármacos desde su introducción en la práctica clínica. Esto ha facilitado la selección de bacterias multirresistentes y su diseminación en los ambientes microbianos. Los plásmidos tienen un papel fundamental en la dispersión de resistencias, pues son capaces de transmitirse horizontalmente entre distintas poblaciones bacterianas, diseminando de esta forma los genes de resistencia a antimicrobianos. Cuando una bacteria adquiere un nuevo plásmido, no obstante, la replicación y expresión de los genes codificados en el plásmido puede suponer un elevado coste biológico para la bacteria, produciendo una ralentización de su crecimiento y menor competitividad frente a las bacterias libres del plásmido. En ambientes en los que no existe una presión selectiva, esto puede suponer la pérdida del plásmido en la población bacteriana. El coste biológico de los plásmidos puede ser compensado mediante evolución adaptativa, que permite la adaptación de los plásmidos a sus nuevos hospedadores y facilita su persistencia en la población. Sin embargo, la mayoría de los mecanismos de adaptación descritos son exclusivos de plásmidos conjugativos, y no pueden aplicarse a los plásmidos pequeños no conjugativos...
During the recent years, the levels of antimicrobial resistance have been drastically increasing. This increase is exacerbated by the misuse of antibiotics since they were introduced into clinical practice, which has facilitated the selection of multiresistant bacteria and their dissemination in microbial environments.Plasmids play a fundamental role in the dissemination of antibiotic resistance, as they can be transmitted horizontally among bacterial populations, leading to the spread of the resistance genes they harbor. However, when a bacterium acquires a new plasmid, the replication and translation of the genes encoded in the plasmid can produce a biological cost to the bacterium, which generates a growth deceleration and lower competitiveness against plasmid-free bacteria. In environments where there is no selective pressure, this could result in the loss of the plasmid in the bacterial population. The biological cost imposed by plasmids can be compensated by adaptive evolution, which allows the adaptation of plasmids to novel hosts and facilitates their persistence in the population. Nevertheless, most adaptive mechanisms described in literature are exclusively on conjugative plasmids and cannot be applied to small non-conjugative plasmids...
During the recent years, the levels of antimicrobial resistance have been drastically increasing. This increase is exacerbated by the misuse of antibiotics since they were introduced into clinical practice, which has facilitated the selection of multiresistant bacteria and their dissemination in microbial environments.Plasmids play a fundamental role in the dissemination of antibiotic resistance, as they can be transmitted horizontally among bacterial populations, leading to the spread of the resistance genes they harbor. However, when a bacterium acquires a new plasmid, the replication and translation of the genes encoded in the plasmid can produce a biological cost to the bacterium, which generates a growth deceleration and lower competitiveness against plasmid-free bacteria. In environments where there is no selective pressure, this could result in the loss of the plasmid in the bacterial population. The biological cost imposed by plasmids can be compensated by adaptive evolution, which allows the adaptation of plasmids to novel hosts and facilitates their persistence in the population. Nevertheless, most adaptive mechanisms described in literature are exclusively on conjugative plasmids and cannot be applied to small non-conjugative plasmids...
Description
Tesis inédita de la Universidad Complutense de Madrid, Facultad de Veterinaria, Departamento de Bioquímica y Biología Molecular, leída el 22-10-2019