We discuss the possibility of controlling biological systems, by exciting in the near infrared region hybrid metallic nanotube ropes, dressed with proteins and embedded in the biosystems. If one nanotube, in a double-tube rope, is filled with metallofullerenes and the other is empty, the two tubes change their opposite equilibrium charging during the irradiation. The resulting change of the local electric field can deform proteins attached to the tubes, and change their catalytic properties. (C) 2003 Elsevier B.V. All rights reserved.