Listeria monocytogenes rotates around its long axis during actin-based motility

摘要

Actin-based motility of the Gram-positive bacterium Listens monocytogenes is an analog of eukaryotic cell motility and has long been the subject of biochemical and biophysical investigations (reviewed in [1]). Only one bacterial factor--ActA--is required for the movement of L monocytogenes [2-4]. Biophysical mechanisms have been proposed to explain the conversion of actin polymerization into propulsive force [5-11], but none predicts a torsional force. Surprisingly, we find that L. monocytogenes rotates around its long axis as it is propelled by actin polymerization. In contrast, Gram-negative bacteria do not rotate if actin-based motility is directed by IcsA (VirG), a Shigella flexneri protein unrelated to ActA [3,12,13].