Regulation, excision and horizontal transfer of genomic islands in bacteria

Abstract:

Horizontal gene transfer (HGT) is a common mechanism for the exchange of genetic information between bacterial species, which contributes to the diversification and adaptation of microorganisms. Mobile genetic elements (MGEs), the drivers of HGT, are segments of DNA that encode enzymes and other proteins that mediate the movement of DNA within genomes (intracellular mobility) or between bacterial cells (intercellular mobility). Genomic island is an important MGE in bacteria. Mobile genomic islands are able to integrate into the chromosome of the host, from which they get excised under favorable conditions and are then transferred to a new host via transformation, conjugation or transduction. Genomic islands have a variety of biological function, such as antibiotic resistance, pathogenicity, xenobiotic degradation and heavy metal resistance. Genomic islands are mediated by integrase and regulated by diverse transcription factors in the process of metastasis. In this review, we evaluate the progress in regulation, excision and horizontal transfer of genomic islands in bacteria.