Details

Autor(en) / Beteiligte

• Lough, Wilson
• Weibel, Douglas B
• Spagnolie, Saverio E

Titel

Self-buckling and self-writhing of semi-flexible microorganisms

Ist Teil von

• Soft matter, 2023-10, Vol.19 (38), p.7349-7357

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The twisting and writhing of a cell body and associated mechanical stresses is an underappreciated constraint on microbial self-propulsion. Multi-flagellated bacteria can even buckle and writhe under their own activity as they swim through a viscous fluid. New equilibrium configurations and steady-state dynamics then emerge which depend on the organism's mechanical properties and on the oriented distribution of flagella along its surface. Modeling the cell body as a semi-flexible Kirchhoff rod and coupling the mechanics to a flagellar orientation field, we derive the Euler-Poincaré equations governing the dynamics of the system, and rationalize experimental observations of buckling and writhing of elongated swarmer cells of the bacterium Proteus mirabilis . A sequence of bifurcations is identified as the body is made more compliant, due to both buckling and torsional instabilities. These studies highlight a practical requirement for the stiffness of bacteria below which self-buckling occurs and cell motility becomes ineffective. Motility of multiflagellated cells requires a delicate balance between flagellar activity, geometry, and mechanical properties of the cell body.