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Modeling of the Chemistry of the Active Site of Galactose Oxidase

1996; Wiley; Volume: 35; Issue: 15 Linguagem: Inglês

10.1002/anie.199616871

ISSN

1521-3773

Autores

J.A. Halfen, Victor G. Young, William B. Tolman,

Tópico(s)

Enzyme-mediated dye degradation

Resumo

Angewandte Chemie International Edition in EnglishVolume 35, Issue 15 p. 1687-1690 Communication Modeling of the Chemistry of the Active Site of Galactose Oxidase† Jason A. Halfen, Jason A. Halfen Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this authorDr. Victor G. Young Jr, Dr. Victor G. Young Jr Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this authorProf. William B. Tolman, Corresponding Author Prof. William B. Tolman Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this author Jason A. Halfen, Jason A. Halfen Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this authorDr. Victor G. Young Jr, Dr. Victor G. Young Jr Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this authorProf. William B. Tolman, Corresponding Author Prof. William B. Tolman Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Department of Chemistry University of Minnesota 207 Pleasant Street S. E., Minneapolis, MN 55455 (USA) Fax: Int. code +(612)624-7029 e-mail: [email protected]Search for more papers by this author First published: August 1996 https://doi.org/10.1002/anie.199616871Citations: 86 † This work was supported by grants from the National Institutes of Health (GM 47365), the National Science Foundation (National Young Investigator Award to W. B. T.), the Alfred P. Sloan and Camille and Henry Dreyfus Foundations (fellowships to W. B. T.), and the University of Minnesota (Dissertation Fellowship to J. A. H.). One of the diffractometers used was purchased in part from funds from the NSF (CHE-9413114). AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Graphical Abstract Sterically hindered triazacyclononane derivatives bearing one alkyl-substituted phenolato group have enabled the synthesis of copper complexes that mimic key intermediates in the postulated catalysis cycle of galactose oxidase. For example, one-electron oxidation of the copper(II) complex pictured on the right yields benzaldehyde, probably with participation of a CuII complex containing a phenoxyl radical. A similar mechanism has been proposed for the active enzyme. References 1(a) J. A. Stubbe, Annu. Rev. Biochem. 1989, 58, 257–285; (b) J. Z. Pedersen, A. Finazzi-Agro, FEBS Let., 1993, 325, 53–58. 2(a) J. W. Whittaker in Metalloenzymes Involving Amino Acid Residue and Related Radicals, Vol. 30 (Eds.: H. Sigel, A. Sigel), Marcel Dekker, New York, 1994, pp. 315–360; (b) P. F. Knowles, N. Ito in Perspectives in Bio-inorganic Chemistry, Vol. 2, Jai Press LTD, London, 1994, pp. 207–244. 3(a) A. J. Baron, C. Stevens, C. Wilmot, K. D. Seneviratne, V. Blakeley, D. M. Dooley, S. E. V. Phillips, P. F. Knowles, M. J. McPherson, J. Biol. Chem. 1994, 269, 25095–25105; (b) P. F. Knowles, R. D. Brown III, S. H. Koenig, S. Wang, R. A. Scott, M. A. McGuirl, D. E. Brown, D. M. Dooley, Inorg. Chem. 1995, 34, 3895–3902. 4(a) N. Ito, S. E. V. Phillips, C. Stevens, Z. B. Ogel, M. J. McPherson, J. N. Kee1n, K. D. S. Yadav, P. F. Knowles, Nature 1991, 350, 87–90; (b) N. Ito, S. E. V. Phillips, C. Stevens, Z. B. Ogel, M. J. McPherson, J. N. Keen, K. D. S. Yadav, P. R. Knowles, Faraday Discuss. 1992, 93, 75–84; (c) N. Ito, S. E. V. Phillips, K. D. S. Yadav, P. F. Knowles, J. Mol. Biol. 1994, 238, 794–814. 5 An alternative route involving deprotonation by the stacked tryptophan residue also has been suggested [4b]. 6(a) B. P. Branchaud, M. P. Montague-Smith, D. J. Kosman, F. R. McLaren, J. Am. Chem. Soc. 1993, 115, 798–800; (b) K. Clark, J. E. Penner-Hahn, M. M. Whittaker, J. W. Whittaker, J. Am. Chem. Soc. 1990, 112, 6433–6434; (c) R. M. Wachter, B. P. Branchaud, J. Am. Chem. Soc. 1996, 118, 2782–2789. 7(a) U. Rajendran, R. Viswanathan, M. Palaniandavar, M. Lakshminarayanan, J. Chem. Soc. Dalton Trans. 1992, 3563–3564; (b) R. Uma, R. Viswanathan, M. Palaniandavar, M. Lakshminarayanan, J. Chem. Soc. Dalton Trans. 1994, 1219–1226; (c) H. Adams, N. A. Bailey, D. E. Fenton, Q. He, Inorg. Chim. Acta 1994, 215, 1–3; (d) H. Adams, N. A. Bailey, C. O. R. de Barbarin, D. E. Fenton, Q.-Y. He, J. Chem. Soc. Dalton Trans. 1995, 2323–2331; (e) M. Whittaker, Y. Chuang, J. Whittaker, J. Am. Chem. Soc. 1993, 115, 10029–10035; (f) N. Kitajima, K. Whang, Y. Moro-oka, A. Uchida, Y. Sasada, J. Chem. Soc. Chem. Commun. 1986, 1504–1505; (g) M. M. Whittaker, W. R. Duncan, J. W. Whittaker, Inorg. Chem. 1996, 35, 382–386. 8 J. Laugier, J.-M. Latour, A. Caneschi, P. Rey, Inorg. Chem. 1991, 30, 4474–4477. 9 X-ray crystal structure analysis of 1: purple block crystal (0.50 × 0.50 × 0.20 mm); C21H36ClCuN3O, Mr = 445.53, monoclinic, space group P21/c, a = 15.18(4) Å, b = 7.538(1) Å, c = 20.58(5) Å, β = 109.1(1)°, V = 2225(8) Å3, Z = 4 at 298(2) K; ρcalcd 1.330 g cm−3; 2θmax = 50.00°; μMO = 11.19 cm−1. The structure was solved by direct methods; hydrogen atoms were placed at calculated positions but were not refined. A semiempirical absorption correction (DIFABS) was applied. The final cycle of full-matrix least-squares refinement (on F), based on 4319 reflections [I2σ(I)] and 245 variable parameters, converged at R = 0.071 and wR = 0.096 (max/min residual electron density 0.72/-1.03 e− Å−3). Data were collected on an Enraf–Nonius CAD-4 diffractometer, and calculations were performed with the TEXSAN software package. X-ray crystal structure analysis of 4·0.5 toluene: green block crystal (0.50 × 0.50 × 0.25 mm); C37,50H59CuN3O2, M = 647.42, monoclinic, space group P21/n, a = 17.5316(4) Å, b = 9.3694(3) Å, c = 22.1187(5) Å, β = 91.444(1)°, V = 3632.1(2) Å3, Z = 4 at 173(2) K; ρcalcd = 1.184 g cm−3; 2θmax = 50.18°; μMO = 6.36 cm−1. The structure was solved by direct methods; non-hydrogen atoms were refined anisotropically, and hydrogen atoms were placed at calculated positions and refined as riding atoms with individual isotropic displacement parameters. A semiempirical absorption correction was applied. A disordered toluene molecule was located on an inversion center; the occupancies of its atoms were fixed at 0.5 to account for the disorder. The final cycle of full-matrix least-squares refinement (on F2), based on 6402 reflections [I2σ(I)] and 495 variable parameters, converged at R1 = 0.0359 and wR2 = 0.0865 (max/min residual electron density 0.264/ −0.369 e Å−3). Data were collected on a Siemens SMART system and calculations were performed using the SHELXTL V5.0 suite of programs. Crystallographic data (excluding structure factors) for the structures reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publications no. CCDC-179-44. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road, Cambridge CB2 1EZ UK (Telefax: Int. code +(1223) 336-033; e-mail: [email protected]). 10 For 1 and 4, τ = 0.07 and τ = 0.03, respectively, where values of 0 or 1, respectively, refer to ideal square-pyramidal or trigonal-bipyramidal geometries as described in A. W. Addison, T. N. Rao, J. Reedijk, J. van Rijn, G. C. Verschoor, J. Chem. Soc. Dalton Trans. 1984, 1349–1356. 11 1: EPR (1:1 CH2Cl2:toluene, 77 K, 9.46 GHz): g = 2.25, A = 152 G, g⊥ = 2.03; UV/Vis (CH2Cl2): λmax (ϵ) = 340 (3.1 × 103), 520 (1.5 × 103), 710 nm (sh, 440). 2: EPR (1:1 CH2Cl2:toluene, 77 K, 9.46 GHz): g = 2.26, A = 153 G, g⊥ = 2.04; UV/Vis (CH2Cl2): λmax (ϵ) = 350 (3.0 × 103), 526 (1.2 × 103), 720 nm (sh, 400). 3: EPR (1:1 CH2Cl2:toluene, 77 K, 9.46 GHz): g = 2.25, A = 152 G, g⊥ = 2.03; UV/Vis (CH2Cl2): λmax (ϵ) 328 (3.3 × 103), 532 (1.1 × 103), 696 nm (sh, 450). 4: EPR (1:1 THF:toluene, 77 K, 9.46 GHz): gz = 2.26, Az = 153 G, gy = 2.03, gx = 2.02; UV/Vis (THF): λmax (ϵ) = 436 (700), 760 nm (130). 12 Oxidation of 1 was irreversible (Epa = + 0.71 V vs. SCE at 100 mVs−1 with 0.2 M Bu4NPF6 in CH2Cl2). 13 M. M. Whittaker, J. W. Whittaker, J. Biol. Chem. 1988, 263, 6074–6080. 14 E. R. Altwicker, Chem. Rev. 1967, 67, 475–531. 15 Report describing species in which phenoxyl radicals are coordinated to iron: J. Hockertz, S. Steenken, K. Wieghardt, P. Hildebrandt, J. Am. Chem. Soc. 1993, 115, 11222–11230. 16 T. Steiner, W. Saenger, J. Am. Chem. Soc. 1993, 115, 4540–4547, and references cited therein. 17 R. P. Houser, J. A. Halfen, V. G. Young, Jr., N. J. Blackburn, W. B. Tolman, J. Am. Chem. Soc. 1995, 117, 10745–10746. 18 D. A. Moore, P. E. Fanwick, M. J. Welch, Inorg. Chem. 1989, 28, 1504–1506. Citing Literature Volume35, Issue15August 1996Pages 1687-1690 ReferencesRelatedInformation

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