Emergent chirality in bacterial active suspensions

Chirality is a ubiquitous phenomenon in nature spanning from molecular scale to galactic scale, such as the helical structure of DNA strands to the spiral shape of galaxies. Bacterial populations consisting of a large number of cells may also develop chiral structures due to microscopic chirality at the single cell level. Here we study the the emergence of chiral structures in bacterial suspensions arising from spontaneous chiral symmetry breaking in the collective motion of cells. Our study may offer a deeper understanding of bacterial self-organization and provide new insight to the self-assembly of living materials.