Plesiomonas shigelloides, an atypical Enterobacterales with a Vibrio-related secondary chromosome. The composite genome of Plesiomonas shigelloides

Vibrionales and Enterobacterales are two closely related orders that derive from a common ancestor. While Vibrionales regroup only multi-chromosome species, Enterobacterales are known to be mono-chromosome bacteria. What are the features and factors needed to ensure the sustainability of multiple chromosomes in a cell? We addressed this question by searching and identifying an Enterobacteria with multiple chromosome, Plesiomonas shigelloides, and by carring out a comparative analysis of its genome and proteome with those of mono-chromosome Enterobacterales and Vibrionales.