The Dynamic Bacterial Genome: Horizontal gene transfer and bacterial genomic legacies

摘要: Molecular biologists have long used viruses, plasmids, transposons, and other “vectors” as tools to directly manipulate the genetic makeup of experimental organisms. In nature, these tool vectors originated in species, usually bacteria, facilitators horizontal (also known lateral) gene transfer (HGT). contrast vertical inheritance, where transmission material occurs vertically from parent offspring, HGT refers exchange genes between distantly related strains species. As described this volume, there are many examples species such that mediated by plasmids phages, which bear responsible for pathogenicity antibiotic resistance. is also occur eukaryotes; example, DNA transposons been suggested being horizontally transferred different fruitfly Drosophila (Bushman, 2002). These on a relatively recent evolutionary timescale. However, might had pivotal role more ancient times. Comparative analyses molecular data exploding genome sequencing projects indicates main driving force behind evolution cellular life (Brown, 2003). The reason believing occurrence simple. an context, not found they expected be. most fundamental subdivisions living organisms three urkingdoms or domains life: Archea (traditionally called “archaebacteria”), Bacteria “eubacteria”), Eucarya (interchangeable here elsewhere with term “eukaryote”; Woese, Kandler, Wheelis, 1990).