Synthesis, structure, properties, and phosphatase-like activity of the first heterodinuclear Fe(III)Mn(II) complex with the unsymmetric ligand H(2)BPBPMP as a model for the PAP in sweet potato.
The new heterodinuclear mixed valence complex [Fe(III)Mn(II)(BPBPMP)(OAc)(2)]ClO(4) (1) with the unsymmetrical N(5)O(2) donor ligand 2-bis[((2-pyridylmethyl)-aminomethyl)-6-((2-hydroxybenzyl)(2-pyridylmethyl))-aminomethyl]-4-methylphenol (H(2)BPBPMP) has been synthesized and characterized. Compound 1 crystallizes in the monoclinic system, space group P2(1)/c, and has an Fe(III)Mn(II)(mu-phenoxo)-bis(mu-carboxylato) core. Two quasireversible electron transfers at -870 and +440 mV versus Fc/Fc(+) corresponding to the Fe(II)Mn(II)/Fe(III)Mn(II) and Fe(III)Mn(II)/Fe(III)Mn(III) couples, respectively, appear in the cyclic voltammogram. The dinuclear Fe(III)Mn(II) center has weakly antiferromagnetic coupling with J = -6.8 cm(-1) and g = 1.93. The (57)Fe Mössbauer spectrum exhibits a single doublet, delta = 0.48 mm s(-1) and DeltaE(Q) = 1.04 mm s(-1) for the high spin Fe(III) ion. Phosphatase-like activity at pH 6.7 with the substrate 2,4-bis(dinitrophenyl)phosphate reveals saturation kinetics with the following Michaelis-Menten constants: K(m) = 2.103 mM, V(max) = 1.803 x 10(-5) mM s(-1), and k(cat) = 4.51 x 10(-4) s(-1).
Departamento de Química, Universidade Federal de Santa Catarina, Campus Trindade, BR-88040-900 Florianópolis-SC, Brazil.
Peter
P
Karsten
Ademir
A
Neves
Adailton J
AJ
Bortoluzzi
Mauricio
M
Lanznaster
Valderes
V
Drago
D000135:Acid Phosphatase / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005290:Ferric Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D027723:Ipomoea batatas / Q000201:enzymology*; D007700:Kinetics; D008024:Ligands; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D013379:Substrate Specificity
C472285:(Fe(III)Mn(II)(BPBPMP)(OAc)(2))ClO(4); D005290:Ferric Compounds; D007202:Indicators and Reagents; D008024:Ligands; D009942:Organometallic Compounds; D008345:Manganese; D000135:Acid Phosphatase