We report on a new method to make nanostructures in aqueous solution at roo
m temperature. We used the protein cytochrome c(3) to catalyze reduction of
selenate (SeO42-) to selenium Se-0 by dithionite. Reduction was instantane
ous. After a week spherical nanoparticles of red Se-0 (about 50 nm diameter
) precipitated, followed by self-assembling into crystalline nanowires, typ
ically 1 mu m long. The nanowires were composed of one strand of spherical
particles; thicker strands contained several nanoparticles in parallel.