Samaneh Rahbar

Significance Structural and morphological complexities in bacterial colonies emerge from the interplay of mechanical stresses, environmental conditions, and bacterial properties. Confinement stiffness significantly influences the development of stresses and self-organized ordering in colonies. Mechanosensitivity further complicates the dynamics by linking growth rates to mechanical forces, thus altering cell length, spatial arrangements, and colony structure.

Abstract We numerically study three-dimensional colonies of nonmotile stress-responsive bacteria growing under confining isotropic pressure in a nutrient-rich environment. We develop a novel simulation method to demonstrate how imposing an external pressure leads to a denser aggregate and strengthens the mechanical interactions between bacteria.