15 August 1986
Vol 233, Issue 4765

About The Cover

(Upper) Three-dimensional structure of an antigen-antibody complex. The antigen is lyzozyme (green, with a protruding residue, glutamine-121 in red). (Lower) The antigen and the antibody have been pulled apart to reveal their complementary contacting surfaces. See pages 747 and 755. [A. G. Amit et al., Institut Pasteur, Paris, France]