Journal:Environmental Science and Pollution Research
Key Words:Cd 2+ . Phycocyanin . Toxicity . Fluorescencecharacteristics . Moleculestructure
Abstract:The pollution of heavy metals is a severer problem for the ecosystems in waters. The toxicity of Cd 2+ on phycocyanin (PC) is studied in molecular level in this work. The fluorescence quenching of PC is observed by the adding Cd 2+ from 0 to 500× 10 −7 mol L −1 . From the theoretical calculation and the time-resolved fluorescence decay profiles, the fluorescence quenching of PCbyCd 2+ isfound to bestatic.The synchronous fluorescencespectraareusedtostudy the changeinamino acidresiduesofPC molecules, indicating that the effect of Cd 2+ on the Trp of PC is more significant than the Tyr. The UV-Vis absorbance of tetrapyrrole decreases from 0.26 to 0.23 cps with increasing Cd 2+ concentration, suggesting that Cd 2+ affects the light adsorption and the photosynthesis function of PC. The circular dichroism spectra reveal that adding Cd 2+ also changes the secondary structure (α-helix) of PC.
Indexed by:Article
Volume:25
Issue:2018
Page Number:14544-14550
Translation or Not:no
Links to published journals:https://doi.org/10.1007/s11356-018-1686-y