| Autor: |
Camargo MA; Laboratório de Bioinorgânica e Crystalografia, Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, Santa Catarina, Brazil., Neves A, Szpoganicz B, Bortoluzzi AJ, Fischer FL, Terenzi H, Castellano EE |
| Jazyk: |
angličtina |
| Zdroj: |
Inorganic chemistry [Inorg Chem] 2010 Mar 15; Vol. 49 (6), pp. 3057-63. |
| DOI: |
10.1021/ic100276z |
| Abstrakt: |
The new trinuclear gadolinium complex [Gd(3)L(2)(NO(3))(2)(H(2)O)(4)]NO(3).8H(2)O (1) with the unsymmetrical ligand 2-[N-bis-(2-pyridylmethyl)aminomethyl]-4-methyl-6-[N-bis(2-hydroxy-2-oxoethyl)aminomethyl] phenol (H(3)L) was synthesized and characterized. The new ligand H(3)L was obtained in good yield. Complex 1 crystallizes in an orthorhombic cell, space group Pcab. Kinetic studies show that complex 1 is highly active in the hydrolysis of the substrate 2,4-bis(dinitrophenyl)phosphate (K(m) = 4.09 mM, V(max) = 2.68 x 10(-2) mM s(-1), and k(cat) = V(max)/[1] = 0.67 s(-1)). Through a potentiometric study and determination of the kinetic behavior of 1 in acetonitrile/water solution, the species present in solution could be identified, and a trinuclear monohydroxo species appears to be the most prominent catalyst under mild conditions. Complex 1 displays high efficiency in DNA hydrolytic cleavage, and complete kinetic studies were carried out (K(m) = 4.57 x 10(-4) M, k'(cat) = 3.42 h(-1), and k'(cat)/K(m) = 7.48 x 10(3) M(-1) h(-1)). Studies with a radical scavenger (dimethyl sulfoxide, DMSO) showed that it did not inhibit the activity, indicating the hydrolytic action of 1 in the cleavage of DNA, and studies on the incubation of distamycin with plasmid DNA suggest that 1 is regio-specific, interacting with the minor groove of DNA. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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