title: In vitro investigation of the interaction between pentachlorophenol and alkaline phosphatase by spectroscopic methods.
abstract: The interaction characteristics of alkaline phosphatase (ALP) with pentachlorophenol (PCP) were investigated using fluorescence, UV-vis absorption, and circular dichroism (CD) techniques. Results obtained from analysis of fluorescence intensity indicated that PCP has a strong ability to quench the intrinsic fluorescence of ALP through a static quenching procedure. The thermodynamic parameters ΔH and ΔS were observed to be -4.60kJmol(-1) and 54.59Jmol(-1)K(-1), respectively, and the value of ΔG was negative. These results indicate that the binding reactions were spontaneous, and both hydrophobic and electrostatic forces were involved in the interaction of PCP and ALP. Based on Forster's theory of non-radiation energy transfer, the binding distance, r, between the ALP and PCP was evaluated to be 2.50nm and the critical distance R(0) was 2.26nm. The CD spectra results showed that the α-helicity was decreased from 49.68% in native ALP to 47.28% in PCP-ALP systems, which indicate the secondary structure of ALP was changed slightly in the presence of PCP.
authors.affiliation: School of Resource and Environmental Science, Wuhan University, Wuhan 430079, China.
authors.forename: Qiongyu
authors.initials: Q
authors.lastname: Liu
authors.forename: Peijiang
authors.initials: P
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D004785:Environmental Pollutants / Q000378:metabolism*; D010416:Pentachlorophenol / Q000378:metabolism*; D010575:Pesticides / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics
chemical_list: D004785:Environmental Pollutants; D010575:Pesticides; D010416:Pentachlorophenol; D000469:Alkaline Phosphatase