DNA binding, BSA interaction and SOD activity of two new nickel(II) complexes with glutamine Schiff base ligands.
Two hexacoordinated octahedral nickel(II) complexes, [Ni(o-van-gln)(phen)(H2O)](1) and [Ni(sal-gln)(phen)(H2O)](2) [o-van-gln=a Schiff base derived from o-vanillin and glutamine, sal-gln=a Schiff base derived from salicylaldehyde and glutamine, phen=1,10-phenanthroline], have been synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. X-ray studies showed that nickel atoms of both 1 and 2 exhibit distorted NiN3O3 octahedral geometry. In each crystal, intermolecular hydrogen bonds form a two-dimensional network structure. DNA-binding properties of these two nickel(II) complexes were investigated by using UV-Vis absorption, fluorescence, circular dichroism (CD) spectroscopies and viscosity measurements. Results indicated that the two complexes can bind to calf thymus DNA (CT-DNA) via an intercalative mode, and complex 1 exhibits higher interaction with CT-DNA than complex 2. Furthermore, the interactions between the nickel(II) complexes with bovine serum albumin (BSA) have been studied by spectroscopies. The results indicated that both complexes could quench the intrinsic fluorescence of BSA in a static quenching process. The binding constants (Kb) and the numbers of binding sites (n) obtained are 1.10×10(5)M(-1) and 1.05 for complex 1 and 5.05×10(4)M(-1) and 0.997 for complex 2, respectively. Site-selective competitive binding investigation indicated that the binding sites of both the complexes are located in site I of sub-domains IIA of BSA. Assay of superoxide dismutase (SOD) activity of the nickel(II) complexes revealed that they exhibit significant superoxide scavenging activity with IC50=3.4×10(-5)M for complex 1 and 4.3×10(-5)M for complex 2, respectively.
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Qiang
Q
Wei
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China; Department of Material Science, Shandong Polytechnic Technician College, Liaocheng 252027, China.
Jianfang
J
Dong
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Peiran
P
Zhao
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Manman
M
Li
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Fengling
F
Cheng
School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei, Nanjing 210094, China.
Jinming
J
Kong
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China. Electronic address: lilianzhi1963@163.com.cn.
Lianzhi
L
Li
D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D005973:Glutamine / Q000737:chemistry*; D008024:Ligands; D008968:Molecular Conformation; D009532:Nickel / Q000737:chemistry*; D010618:Phenanthrolines / Q000737:chemistry; D011485:Protein Binding; D012545:Schiff Bases / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism*; D014783:Viscosity
D056831:Coordination Complexes; D008024:Ligands; D010618:Phenanthrolines; D012545:Schiff Bases; D005973:Glutamine; D012710:Serum Albumin, Bovine; D009532:Nickel; D004247:DNA; C427203:calf thymus DNA; D013482:Superoxide Dismutase; C025205:1,10-phenanthroline
BSA; DNA; Glutamine Schiff base; Nickel(II) complex; SOD activity