Microoxen: Microorganisms to move microscale loads

TLDR

Harnessing biological motors for mechanical work outside cells is challenging, requiring in vitro reconstitution and protein engineering of nanomotors. The study aims to develop a method that harnesses biological motor power using intact cells. The method employs Chlamydomonas reinhardtii as microoxen, attaching 1–6 µm polystyrene beads via surface chemistry, steering cells with phototaxis, and releasing loads with photochemistry. These microoxen transport 3 µm beads at 100–200 µm s⁻¹ over distances up to 20 cm.

Abstract

It is difficult to harness the power generated by biological motors to carry out mechanical work in systems outside the cell. Efforts to capture the mechanical energy of nanomotors ex vivo require in vitro reconstitution of motor proteins and, often, protein engineering. This study presents a method for harnessing the power produced by biological motors that uses intact cells. The unicellular, biflagellated algae Chlamydomonas reinhardtii serve as “microoxen.” This method uses surface chemistry to attach loads (1- to 6-μm-diameter polystyrene beads) to cells, phototaxis to steer swimming cells, and photochemistry to release loads. These motile microorganisms can transport microscale loads (3-μm-diameter beads) at velocities of ≈100–200 μm·sec –1 and over distances as large as 20 cm.