The evolutionary dynamics of integrons in changing environments

摘要: Integrons are genetic elements that common in bacteria and hotspots for genome evolution. They facilitate the acquisition reassembly of gene cassettes encoding a variety functions, including drug resistance. Despite their importance clinical settings, selective forces responsible evolution maintenance integrons poorly understood. We present mathematical model integron within bacterial populations subject to fluctuating antibiotic exposures. Bacteria carrying functional integrase mediates reshuffling cassette genes thereby modulates expression patterns compete with without integrase. Our results indicate wide range parameters, can be stably maintained population despite substantial fitness costs. This advantage arises because gene-cassette shuffling generates diversity, thus enabling respond rapidly changing pressures. also show horizontal transfer promotes stable lead de novo assembly integrons. testable predictions evolution, loss integrases environments selection intermediate gene-shuffling rates environments. highlight need experimental studies biology.