06 September 1996
Vol 273, Issue 5280

About The Cover

Mutants in complementary chromatic adaptation isolated from the filamentous cyanobacterium Fremyella displosiphon. Each of the four mutants shown has a lesion in a separate step of the signal transduction pathway controlling complementary chromatic adaptation and shows a different color during growth. The red cells (center, red mutants) are response regulator mutants, and the grayish colonies (upper left, black mutants) are defective in a sensor with similarity to plant phytochromes. See page 140. [Image: Gregory O. Lam-Niemeyer]