Credit: Image courtesy of Trevor Douglas, Indiana University
Densely packed, these nanoscale bioreactors convert water to hydrogen. These tiny reactors are based on biological functionality and are synthesized through a process called “directed assembly” in which researchers manipulate the system’s natural growth processes to make a new system. The bioreactors are made of hydrogen-producing enzymes (green) within virus protein shells (gray). Directed assembly resulted in confining the enzymes within the virus shells, which led to a more stable and active hydrogen-forming material.