Chromatic adaptation and the evolution of light color sensing in cyanobacteria

摘要

One of the most fascinating recent developments in the field of microbiology is the growing recognition that a large number of bacterial species are capable of sensing and responding to many different light colors. Much of this has come from analysis of bacterial genome sequences, which has shown that genes encoding a superfamily of phytochrome-class photoreceptors exist in both nonphoto-synthetic and photosynthetic prokaryotes (1). Cyanobacteria, which make their living via photosynthesis, contain an especially large number of genes encoding such photoreceptors. As yet, the mechanisms and cellular roles of most of these have not been elucidated. In PNAS, Hirose et al. (2) provide interesting new insights into a cyanobacterial phytochrome-regulated sensory system that controls the production of proteins used to capture light for photosynthesis, raising new possibilities to explain how such systems evolved.