Study on Conformation of Escherichia Coli Alkaline Phosphatase by Intrinsic tryptophan Room Temperature Phosphorescence Probe

Room temperature phosphorescence(RTP) probe is a powerful tool for studying the kinetics and relationship between the conformation change and physiological function of protein because some slow kinetic processes of protein in solution just occur the same time scales as phosphorescence lifetime and it susceptibly indicates microenvironment properties. RTP of Escherichia coli alkaline phosphatase(AP) comes mainly from tryptophan residues (Trp-109). It is well known that the deeper Trp-109 is embedded, The stronger phosphorescence emitting is, and the longer its lifetime is. The current work is a preliminary study of the conformation changes of AP, the local microenvironment of Trp-109 and the quenching kinetic natures in the unfolded processes of AP in the presence of different denaturants.