Effects of blue light on respiration and carbon dioxide fixation in colorlessChlorellamutant cells

摘要

A colorless mutant ofChlorella vulgaris(Mutant#125) starved in darkness, showed suppressed rates of respiration and dark CO2fixation, which were significantly recovered by illumination with blue light. The main CO2fixation product under blue light was aspartate. Such enhancements did not take place in cells actively growing in the glucose medium. Both enhancing effects of blue light (456 nm) were saturated at light intensities as low as 400–800 erg.cm-2.sec-1. The action spectra for these enhancing effects were similar to each other; both showed peaks at 460 nm and 380 nm, which correspond to the absorption maxima of flavin. All these findings indicate that the same mechanism underlies the observed effects of blue light on CO2fixation and respiration. The role of blue light which brings about the enhancements in CO2fixation and respiration is discusse