Mechanobiology of bacterial biofilms: from structure and rheology to developmental dynamics and environmental adaptation

Bacterial biofilms represent a dominant mode of microbial life with profound implications for healthcare, industry, and environmental systems. The mechanical properties of biofilms fundamentally govern their structural development, functional performance, and resilience to external stresses. This review presents a comprehensive multiscale framework integrating experimental techniques and computational modeling to elucidate how mechanics drive biofilm architecture and evolution. We examine the mechanistic basis of initial bacterial attachment, growth-induced mechanical instabilities underlying morphogenesis, and hydrodynamic forces controlling detachment dynamics. Advanced characterization methods spanning atomic force microscopy, microfluidic platforms, and microrheology reveal pronounced mechanical heterogeneity arising from spatially variable extracellular matrix composition and cellular organization. Agent-based models and continuum simulations demonstrate how environmental factors, including nutrient gradients, mechanical stress, and physicochemical conditions, modulate both bulk viscoelastic behavior and local mechanical properties. By synthesizing mechanobiological principles across molecular, cellular, and macroscopic scales, this review establishes a foundation for systematic analysis of biofilm mechanics and highlights critical directions for developing predictive multiscale frameworks that integrate biochemical regulation with mechanical responses.