Effects of environmental factors and denaturants on the specific absorption spectrum and fluorescence characters of B-phycoerythrin

Abstract

Effects of environmental factors and denaturants on the variation rules of the specific absorption spectrum and fluorescence emission intensity of B-phycoerythrin were systematically investigated in the present paper. The results showed that B-phycoerythrin was relatively stable under certain conditions: the pH range from 4. 5 to 9. 5, temperature range from 25 to 60°C, and illumination intensity at 2 800 lx in 24 h. The specific absorption spectrum and fluorescence emission intensity of B-phycoerythrin changed slightly. The conformation of Br phycoerythrin changed remarkably with 0. 5% -3% SDS or 0. 25%-l% β-mercaptoethanol, the fluorescence emission intensity declined greatly, and the specific absorption peaks disappeared. The fluorescence emission intensity declined, while the specific absorption spectrum did not change, but the peak intensity reduced slightly with 10%-70% acetonitrile or 2-8 mol · L -1 urea. The possible reasons for the conformation changes of B-phycoerythrin with various environmental factors and different denaturants were briefly discussed.