Open AccessMultilevel populations and the evolution of antibiotic resistance through horizontal gene transfer
Author(s) -
Andam Cheryl P.,
Fournier Gregory P.,
Gogarten Johann Peter
Publication year - 2011
Publication title -
fems microbiology reviews
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.91
H-Index - 212
eISSN - 1574-6976
pISSN - 0168-6445
DOI - 10.1111/j.1574-6976.2011.00274.x
Subject(s) - horizontal gene transfer , biology , gene , genetics , transfer rna , genome , lineage (genetic) , allele , antibiotic resistance , population , evolutionary biology , gene pool , antibiotics , genetic diversity , rna , demography , sociology
Horizontal gene transfer (HGT) can create diversity in the genetic repertoire of a lineage. Successful gene transfer likely occurs more frequently between more closely related organisms, leading to the formation of higher‐level exchange groups that in some respects are comparable to single‐species populations. Genes that appear fixed in a single species can be replaced through distant homologs or iso‐functional analogs acquired through HGT. These genes may originate from other species or they may be acquired by an individual strain from the species pan‐genome. Because of their similarity to alleles in a population, we label these gene variants that are exchanged between related species as homeoalleles. In a case study, we show that biased gene transfer plays an important role in the evolution of aminoacyl‐tRNA synthetases (aaRS). Many microorganisms make use of these genes against naturally occurring antibiotics. We suggest that the resistance against naturally occurring antibiotics is the likely driving force behind the frequent switching between divergent aaRS types and the reason for the maintenance of these homeoalleles in higher‐level exchange groups.