title: Exploring the interaction between picoplatin and human serum albumin: The effects on protein structure and activity.
abstract: For the first time, the effects of picoplatin on the structure and esterase-like catalytic activity of human serum albumin (HSA) have been investigated by spectroscopic approaches and molecular modeling. The circular dichroism (CD) spectral examinations indicated that the binding of picoplatin with HSA induced a slight decrease of a-helix content of protein and unfolded the constituent polypeptides of the protein. The synchronous fluorescence and three-dimensional fluorescence spectral methods were used to estimate the effect of picoplatin on the micro-environmental changes of the Trp and Tyr residues of HSA, indicating that the micro-environment around the Tyr and Trp residue is partly disturbed by picoplatin. UV-vis absorption spectral result indicated the formation of the ground state complex between picoplatin with HSA. The ANS binding assay indicated the existence of competitive combination of picoplatin and ANS with HSA. The studies on the effects of picoplatin on the binding of HSA with bilirubin and heme showed that picoplatin binding caused a change of angle between two chromophores of bound bilirubin and the binding site of picoplatin does not locate in subdomain IB in HSA that bound with heme. The molecular modeling results showed that picoplatin binds to the connection between domain I and domain II by hydrophobic, hydrogen bonds, and van der Waals forces. In addition, HSA maintains most of its esterase activity in the presence of picoplatin. The investigations on how picoplatin interacts with HSA are important for the understanding of the anticancer mechanism and toxicity of platinum-based anticancer drug.
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China. Electronic address: wyqing76@126.com.
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China.
authors.forename: Peirong
authors.initials: P
authors.lastname: Wu
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China.
authors.forename: Xinchun
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China. Electronic address: hxzhm@126.com.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China.
authors.forename: Ligan
authors.initials: L
authors.lastname: Qiu
authors.affiliation: Institute of Applied Chemistry and Environmental Engineering, Yancheng Teachers University, Yancheng City, Jiangsu Province 224002, People's Republic of China. Electronic address: yctu_caojian@126.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Cao
mesh_terms: D001663:Bilirubin / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D002942:Circular Dichroism; D006418:Heme / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D062105:Molecular Docking Simulation; D009944:Organoplatinum Compounds / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D009944:Organoplatinum Compounds; D012709:Serum Albumin; C110525:amminedichloro(2-methylpyridine)platinum(II); D006418:Heme; D001663:Bilirubin
keywords: Activity; Conformational structure; Human serum albumin; Picoplatin