Living Machines

This article provides an insight into National Science Foundation (NSF) funded research and development of biological machines. The goal of these research projects is to build living, multicellular machines that sense, move, and solve real-world health problems. One of the Emergent Behaviors of Integrated Cellular Systems (EBICS) group has developed a biobot that walks. Inspired by the structure of human joints, this walker has two short, stubby legs connected by a bridge. The skeleton is constructed from a soft Jell-O-like 3D-printed skeleton called hydrogel, and surrounded by a band of skeletal muscle. The group genetically engineered the cells to produce a protein called channel rhodopsin, a sensory photorecepter that enables the muscle to contract in response to blue light. This provides an easy on–off switch to activate the muscle spurring the bot to move its legs and walk. As biologists understand better how tissues develop, bioengineers will be able to reverse-engineer development to better program cells to self-assemble to create biological machines. Plans for future bots include different cell types and many more functionalities.