Binding Properties of a New Anti-tumor Component (2,2′-bipyridin octylglycinato Pd(II) nitrate) with Bovine β-lactoglobulin-A and -B
| Autor: | Ali Akbar Saboury, A.A. Moosavi-Movahedi, H. Mansoori-Torshizi, Adeleh Divsalar |
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| Rok vydání: | 2007 |
| Předmět: |
Circular dichroism
Quenching (fluorescence) Molecular Structure Chemistry Circular Dichroism chemistry.chemical_element Lactoglobulins General Medicine Conductivity Binding constant Fluorescence spectroscopy Crystallography Structural Biology Organometallic Compounds Proton NMR Animals Humans Thermodynamics Cattle Binding site Molecular Biology Protein Binding Palladium |
| Zdroj: | Journal of Biomolecular Structure and Dynamics. 25:173-182 |
| ISSN: | 1538-0254 0739-1102 |
| DOI: | 10.1080/07391102.2007.10507166 |
| Popis: | An new water soluble palladium (II) complex of formula [Pd(bpy)(Oct-Gly)]NO(3), (where bpy is 2,2'-bipyridine and Oct-Gly is octylglycine) have been synthesised. The Pd(II) complex has been characterized by elemental analysis and conductivity measurements as well as spectroscopic methods such as infrared, (1)H NMR, and ultraviolet-visible. The interaction between the new Pd(II)-complex (2,2'-bipyridin octylglycinato Pd(II) nitrate), an anti-tumor component, with beta-lactoglobulin-A and -B (BLG-A and -B) was studied by fluorescence spectroscopy and far and near-UV circular dichroism (CD) spectrophotometric techniques. A strong fluorescence quenching interaction of Pd(II) complex with BLG-A and -B was observed. The quenching constant was determined using the modified Stern-Volmer equation. The calculated binding constants of Pd(II) complex with BLG-A and -B were 0.51 and 0.28 (x 10(6) M(-1)) and the corresponding average number of binding sites were 2.8 and 1.5, respectively. Far-UV CD studies showed that the Pd(II) complex can significantly change the secondary structure of BLG-A and -B via an increase in the content of alpha-helix structure, which stabilizes the secondary structure of the proteins. Near-UV CD data clearly indicate the alteration in the tertiary structure of BLG-A and -B due to the interaction with Pd(II) complex. Pd(II) complex can change and stabilize both the secondary and tertiary structures of BLG-A more than BLG-B. These conformational changes may be considered to be a deleterious effect of the designed ligand on the protein structures. The difference in the interaction properties observed for BLG-A and -B with Pd(II) complex is due to the difference in the amino acid sequences between these two variants. |
| Databáze: | OpenAIRE |
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