RT Journal Article SR Electronic T1 Protoplast fusion in Bacillus species produces frequent, unbiased, genome-wide homologous recombination JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.10.06.328625 DO 10.1101/2020.10.06.328625 A1 Leah H. Burdick A1 Jared C. Streich A1 Delyana P. Vasileva A1 Dawn M. Klingeman A1 Hari B. Chhetri A1 J. Christopher Ellis A1 Dan M. Close A1 Daniel A. Jacobson A1 Joshua K. Michener YR 2020 UL http://biorxiv.org/content/early/2020/10/06/2020.10.06.328625.abstract AB In eukaryotes, fine-scale maps of meiotic recombination events have greatly advanced our understanding of the factors that affect genomic variation patterns and evolution of traits. However, in bacteria that lack natural systems for sexual reproduction, unbiased characterization of recombination landscapes has remained challenging due to variable rates of genetic exchange and influence of natural selection. Here, to overcome these limitations and to gain a genome-wide view on recombination, we crossed Bacillus strains with different genetic distances using protoplast fusion. The offspring displayed complex inheritance patterns with one of the parents consistently contributing the major part of the chromosome backbone and multiple unselected fragments originating from the second parent. Computational analyses suggested that this bias is due to the action of restriction-modification systems whereas genome features like GC content and local nucleotide identity did not affect distribution of recombination events around the chromosome. Furthermore, we found that the intensity of recombination is uniform across the genome without concentration into hotspots. Unexpectedly, our results revealed that large species-level genetic distance did not affect key recombination parameters. Our study provides a new insight into the dynamics of recombination in bacteria and a platform for studying recombination patterns in diverse bacterial species.Competing Interest StatementJCS, DPV, DAJ, and JKM are inventors on a patent that has been filed based, in part, on the work reported in this manuscript.