title: Exploring the influence of MPA-capped CdTe quantum dots on the structure and function of lysozyme probing by spectroscopic and calorimetric methods.
abstract: The effect of 3-mercaptopropionic acid (MPA)-capped CdTe quantum dots (QDs) on lysozyme was systematically investigated by spectroscopic methods, enzyme activity assay, and calorimetry techniques. Results show that the MPA-capped CdTe QDs binded to lysozyme through van der Walls forces and hydrogen bondings, causing the decrement of α-helical content (∼7%) and increment of β-sheet content (∼11%) of lysozyme. The binding caused static quenching of the fluorescence, while the microenvironment of aromatic amino acid residues did not show any significant alteration. The lysozyme activity was affected by the increasing exposure of QDs, it was inhibited to 53.77% under a 6 × 10-7M exposure compared with the control group. This work will provide direct evidence about enzyme toxicity of QDs to lysozyme in vitro.
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Jinan, 250100, People's Republic of China.
authors.forename: Lining
authors.initials: L
authors.lastname: Zhao
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Jinan, 250100, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Jinan, 250100, People's Republic of China.
authors.forename: Xun
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Jinan, 250100, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Jinan, 250100, People's Republic of China.
authors.forename: Rutao
authors.initials: R
authors.lastname: Liu
mesh_terms: D015097:3-Mercaptopropionic Acid / Q000737:chemistry*; D000818:Animals; D019187:Cadmium Compounds / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning / Q000379:methods; D002645:Chickens; D005453:Fluorescence; D006860:Hydrogen Bonding; D009113:Muramidase / Q000737:chemistry*; D017433:Protein Structure, Secondary; D045663:Quantum Dots / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013691:Tellurium / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D015097:3-Mercaptopropionic Acid; D009113:Muramidase; D013691:Tellurium; C028337:cadmium telluride
keywords: MPA-capped CdTe QDs; calorimetry; lysozyme; spectroscopy; toxicity