Toward Giving Artificial Cells The Ability To Move
Got legs? Chemists in Japan and Italy are reporting development of self-propelled oil droplets that could provide a basis for giving artificial cells the ability to move. Their collaborative study from the University of Tokyo and Protolife in Venice is scheduled for the August 8 issue of the Journal of the American Chemical Society.
Tadashi Sugawara and colleagues note that efforts to make artificial cells have focused partly on genetics and enabling such cells — which could become biofuel factories and other technological advances — to reproduce. Sugawara’s group previously reported a self-reproducing lipid capsule in JACS. Scientists in the United States recently announced successful transplantation of a bacterial genome, an achievement described as a major step toward creating synthetic forms of life.
The new study focuses on “another essential and perhaps more fundamental characteristic of cells, the ability to move.” In laboratory experiments, the researchers showed that an oil droplet, used to represent an artificial cell, underwent sustained movement through a chemical solution for several minutes until finally coming to a stop.
In doing so, the researchers say, the droplet demonstrated a “primitive form of chemotaxis,” one of the most basic cellular responses in which the cell directs its movement toward the presence of certain chemicals in its environment. The study could provide a blueprint for designing future locomotion systems for artificial cells, the scientists suggest.
J Am Chem Soc. 2007 Jul 6; [Epub ahead of print] Links
Fatty Acid Chemistry at the Oil-Water Interface: Self-Propelled Oil Droplets.
Hanczyc MM, Toyota T, Ikegami T, Packard N, Sugawara T.
Contribution from ProtoLife Srl, Parco Vega, Via della Liberta 12, Marghera, Venice 30175, Italy, and Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan. Fatty acids have been investigated as boundary structures to construct artificial cells due to their dynamic properties and phase transitions. Here we have explored the possibility that fatty acid systems also demonstrate movement. An oil phase was loaded with a fatty acid anhydride precursor and introduced to an aqueous fatty acid micelle solution. The oil droplets showed autonomous, sustained movement through the aqueous media. Internal convection created a positive feedback loop, and the movement of the oil droplet was sustained as convection drove fresh precursor to the surface to become hydrolyzed. As the system progressed, more surfactant was produced and some of the oil droplets transformed into supramolecular aggregates resembling multilamellar vesicles. The oil droplets also moved directionally within chemical gradients and exhibited a type of chemotaxis.
PMID: 17616129 [PubMed – as supplied by publisher]