Structural and spectroscopic features of a cis (hydroxo)-Fe(III)-(carboxylato) configuration as an active site model for lipoxygenases.
In our preliminary communication (Ogo, S.; Wada, S.; Watanabe, Y.; Iwase, M.; Wada, A.; Harata, M.; Jitsukawa, K.; Masuda, H.; Einaga, H. Angew. Chem., Int. Ed. 1998, 37, 2102-2104), we reported the first example of X-ray analysis of a mononuclear six-coordinate (hydroxo)iron(III) non-heme complex, [Fe(III)(tnpa)(OH)(RCO(2))]ClO(4) [tnpa = tris(6-neopentylamino-2-pyridylmethyl)amine; for 1, R = C(6)H(5)], which has a characteristic cis (hydroxo)-Fe(III)-(carboxylato) configuration that models the cis (hydroxo)-Fe(III)-(carboxylato) moiety of the proposed (hydroxo)iron(III) species of lipoxygenases. In this full account, we report structural and spectroscopic characterization of the cis (hydroxo)-Fe(III)-(carboxylato) configuration by extending the model complexes from 1 to [Fe(III)(tnpa)(OH)(RCO(2))]ClO(4) (2, R = CH(3); 3, R = H) whose cis (hydroxo)-Fe(III)-(carboxylato) moieties are isotopically labeled by (18)OH(-), (16)OD(-), (18)OD(-), (12)CH(3)(12)C(18)O(2)(-), (12)CH(3)(13)C(16)O(2)(-), (13)CH(3)(12)C(16)O(2)(-), (13)CH(3)(13)C(16)O(2)(-), and H(13)C(16)O(2)(-). Complexes 1-3 are characterized by X-ray analysis, IR, EPR, and UV-vis spectroscopy, and electrospray ionization mass spectrometry (ESI-MS).
Ogo
Seiji
S
Department of Material and Life Science, Graduate School of Engineering, Osaka University, PRESTO & CREST, Japan Science and Technology Corporation (JST), Suita, Osaka 565-0871, Japan. ogo@chem.eng.osaka-u.ac.jp
Yamahara
Ryo
R
Roach
Mark
M
Suenobu
Tomoyoshi
T
Aki
Michihiko
M
Ogura
Takashi
T
Kitagawa
Teizo
T
Masuda
Hideki
H
Fukuzumi
Shunichi
S
Watanabe
Yoshihito
Y
D000085:Acetates / Q000737:chemistry; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D004578:Electron Spin Resonance Spectroscopy; D007202:Indicators and Reagents; D007553:Isotope Labeling; D008024:Ligands; D008084:Lipoxygenase / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
D000085:Acetates; D007202:Indicators and Reagents; D008024:Ligands; D008084:Lipoxygenase