Mobile DNA elements, such as Insertion Sequence (IS) elements, transposons, integrative elements (e.g. integrative islands), prophages, are key players of bacterial adaptation and evolution. They are currently classified into numerous families of which representatives may be genus- or species-specific. Through their mobility by transposition or integration they shape the bacterial genome and contribute to the adaptation of bacteria to survive changing environmental conditions or to adapt to animal or human hosts and evolve to a pathogenic status. They are also involved in the uptake of foreign DNA via horizontal gene transfer (HGT), ranging in size and function from single genes to pathogenicity islands, or islands providing new surface characteristics, e.g., O-antigen, lipopolysaccharides, and surface proteins. The action of mobile DNA elements and associated HGT may therefore drive evolutionary pathogenic processes that include altered responses to inflammation markers and the evasion of the host immune system (e.g. antigenic variation, deletion/inactivation of important antigen genes, or deletion/inactivation of regulatory genes impacting antigen expression). Mobile DNA elements are also major contributors of spreading antimicrobial resistance genes, some of which are known to mobilize intrinsic chromosomal genes to major carriers of antimicrobial resistance such as plasmids or genomic islands. In addition, IS elements may carry promoter sequences which may activate expression of silent genes following their transposition, and through regulatory interference contribute to enhanced resistance to environmental factors such as antimicrobials or other anti-bacterial factors inside the host. IS-induced enhanced resistance may be the result of overexpression of efflux systems, decreased outer membrane permeability or impact biofilm formation. High throughput sequencing has revealed numerous mobile DNA elements in the bacterial world of which many remain to be functionally characterized. This Research Topic will focus especially on mobile DNA elements that have contributed significantly to pathogen evolution including their acquisition of pathogenicity and/or antimicrobial resistance characteristics. Some of these DNA elements may have a diagnostic value for a specific pathogen and therefore applied research using those elements will also be considered in this Research Topic. All article types of the section Infectious Agents and Disease are welcome for this Research Topic:https://www.frontiersin.org/journals/microbiology/sections/infectious-agents-and-disease#article-types The specific topics of the research topic include, but are not limited to:• Identification and characterization of novel mobile DNA elements (e.g., IS, transposon, island, others) • Distribution of mobile DNA elements and contribution to genome evolution and genomic rearrangement • Mobility mechanisms of IS elements, transposons, genomic islands • Contribution of mobile DNA elements to virulence, antimicrobial resistance, fitness, environmental survival or host-adaptation• Mobile DNA elements as tools for molecular epidemiology, detection and identification of bacterial pathogens
Mobile DNA elements, such as Insertion Sequence (IS) elements, transposons, integrative elements (e.g. integrative islands), prophages, are key players of bacterial adaptation and evolution. They are currently classified into numerous families of which representatives may be genus- or species-specific. Through their mobility by transposition or integration they shape the bacterial genome and contribute to the adaptation of bacteria to survive changing environmental conditions or to adapt to animal or human hosts and evolve to a pathogenic status. They are also involved in the uptake of foreign DNA via horizontal gene transfer (HGT), ranging in size and function from single genes to pathogenicity islands, or islands providing new surface characteristics, e.g., O-antigen, lipopolysaccharides, and surface proteins. The action of mobile DNA elements and associated HGT may therefore drive evolutionary pathogenic processes that include altered responses to inflammation markers and the evasion of the host immune system (e.g. antigenic variation, deletion/inactivation of important antigen genes, or deletion/inactivation of regulatory genes impacting antigen expression). Mobile DNA elements are also major contributors of spreading antimicrobial resistance genes, some of which are known to mobilize intrinsic chromosomal genes to major carriers of antimicrobial resistance such as plasmids or genomic islands. In addition, IS elements may carry promoter sequences which may activate expression of silent genes following their transposition, and through regulatory interference contribute to enhanced resistance to environmental factors such as antimicrobials or other anti-bacterial factors inside the host. IS-induced enhanced resistance may be the result of overexpression of efflux systems, decreased outer membrane permeability or impact biofilm formation. High throughput sequencing has revealed numerous mobile DNA elements in the bacterial world of which many remain to be functionally characterized. This Research Topic will focus especially on mobile DNA elements that have contributed significantly to pathogen evolution including their acquisition of pathogenicity and/or antimicrobial resistance characteristics. Some of these DNA elements may have a diagnostic value for a specific pathogen and therefore applied research using those elements will also be considered in this Research Topic. All article types of the section Infectious Agents and Disease are welcome for this Research Topic:https://www.frontiersin.org/journals/microbiology/sections/infectious-agents-and-disease#article-types The specific topics of the research topic include, but are not limited to:• Identification and characterization of novel mobile DNA elements (e.g., IS, transposon, island, others) • Distribution of mobile DNA elements and contribution to genome evolution and genomic rearrangement • Mobility mechanisms of IS elements, transposons, genomic islands • Contribution of mobile DNA elements to virulence, antimicrobial resistance, fitness, environmental survival or host-adaptation• Mobile DNA elements as tools for molecular epidemiology, detection and identification of bacterial pathogens