This photo shows the colors of the cells of the
cyanobacterium Leptolyngbya sp. strain (JSC-1), which was collected from a hot spring near Yellowstone National Park. The cells were grown in white fluorescent light (WL), green-filtered fluorescent light (GL), red light provided by 645-nm LEDs, or far-red light provided by 710-nm LEDs. Some cyanobacteria are known to appear brown when they are grown in green light and to appear blue-green when they are grown in red light, a process known as complementary chromatic acclimation. Although the cells grown in red light and far-red light look similar, research by Bryant's team showed that the
photosynthetic apparatuses in these two cell types is quite different and is optimized to use light wavelengths longer than 700 nm.