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arXiv · 2010.02182

How Influenza's Spike Motor Works

Falko Ziebert·Igor M. Kulić
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Abstract

While often believed to be a passive agent that merely exploits its host's metabolism, influenza virus has recently been shown to actively move across glycan-coated surfaces. This form of enzymatically driven surface motility is currently not well understood and has been loosely linked to burnt-bridge Brownian ratchet mechanisms. Starting from known properties of influenza's spike proteins, we develop a physical model that quantitatively describes the observed motility. It predicts a collectively emerging dynamics of spike proteins and surface bound ligands that combined with the virus' geometry give rise to a self-organized rolling propulsion. We show that in contrast to a Brownian ratchet, the rotary spike drive is not fluctuation driven but operates optimally as a macroscopic engine in the deterministic regime. The mechanism also applies to relatives of influenza and to man-made analogues like DNA-monowheels and should give guidelines for their optimization.

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Falko Ziebert, Igor M. Kulić. 2020-10-05. How Influenza's Spike Motor Works. https://doi.org/10.1103/physrevlett.126.218101

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