About this Research Topic
A major challenge currently facing bacterial genetics research is the limits of gene manipulation across a diverse array of taxa. Fortunately, nature provides a natural system, horizontal gene transfer (HGT), with the possibility to inform the development of new tools. In addition, because HGT plays an important role in bacterial evolution, studying HGT is crucial to understand gene flow, function, and diversity in bacteria, including in regards to an emerging public health crisis – the spread of antimicrobial resistance. HGT offers bacteria involved in the gene transfer additional adaptive benefits under changing environmental conditions, such as the increased use of antibiotics.
New tools such as next generation sequencing (NGS) permit the study of HGT in new ways, and this has brought the realization that HGT occurs more pervasively than originally suspected. However a systematic and in-depth understanding of HGT is lacking. Classical ways of HGT include transformation (direct DNA absorption), transduction (by viruses or phages), bacterial conjugation (by plasmids), and an atypical way of HGT by integrative conjugative elements (ICEs) has been explored in recent years, which suggests that there might be other new ways of HGT undiscovered. While the scope of HGT elements (together with the functions) and their evolutional origins remains elusive. Further exploration of the detailed mechanism of HGT is needed to advance the field.
HGT overcomes a diverse array of bacteria strategies (e.g. restriction-modification systems and CRISPR-Cas systems) to resist heterogeneous DNA incorporation. This makes the frequency of HGT in the natural environment surprising; understanding of how HGT accomplishes this feat will open the door to new techniques for gene knock-out/knock-in experiments. Studies are needed to further understand how these heterogeneous DNAs (HGT elements) break through the protection barriers and successfully integrate into specific chromosome loci or maintain freely in hosts. In addition to NGS, new technologies including transcriptomics and proteomics are now available to help tackle the questions surrounding HGT. Scientists should take advantage of these tools to study donor and recipient cells where HGT occurs. Exploring HGT will expand our understanding of bacterial evolution and facilitate the development of powerful genetic tools for bacterial manipulation as well as provide insight into the spread of novel bacterial functions such as antimicrobial resistance traits across taxa.
This proposed Research Topic will focus on all areas relating to HGT including the diversity of transferrable genetic elements, functions conveyed on those elements (e.g. antimicrobial resistance and substrate utilization), mechanisms of gene transfer and integration, and mechanisms of overcoming host defenses. Articles on focused on exploring bacterial diversity in the context of HGT are also encouraged.
Keywords: gene, genetic diversity, bacteria, horizontal gene