Preprint Highlight: Hyphal compartmentalization and sporulation in Streptomyces require the conserved cell division protein SepX.

Abstract

Most bacteria undergo binary division. Streptomyces, filamentous soil bacteria with a multicellular life cycle, have two functionally distinct modes of cell division: vegetative cross-wall formation and sporulation septation. Although sporulation septation is an important survival strategy, the physiological significance of cross-wall formation remains largely unknown. Using genetics and quantitative imaging, the authors identified a previously uncharacterized protein, SepX, essential for cross-wall formation and for efficient sporulation septation. Deletion of sepX caused severe growth defects, demonstrating the necessity for vegetative division. These results provide a genetic basis for future research into the regulation of bacterial multicellular development, including how cross-walls form, how they relate to fitness, and how the two distinct cell types are coordinated.