Models copper proteins

In a beautifiil recent work, the groups of K. Pierloot and B. O. Roos have proposed a fairly complete understanding of the relation between the electronic spectra and the stmcture of the mononuclear copper-cysteinate proteins. This theoretical work is based on DFT geometry optimizations of several blue copper protein models from [Cu(NH3)2(SH)(SH2)+] to... 

SHAB theory, 1040 Copper cupferronate vibration frequencies, 511 Copper proteins models, 85 Coprogen... 

TABLE 2. Number of surveyed articles on copper protein models ... 

Models for copper-protein interaction based on solution and crystal structure studies. R. Osterberg, Coord. Chem. Rev., 1974,12, 309-347 (130). 

Blue copper electron transfer proteins, 6,712-717 Blue copper oxidases, 6,699 Blue copper proteins, 2, 557 6, 649 Blue electron transfer proteins, 6,649,652 spectroscopy, 6, 651 Blue oxidases copper, 6,654,655 Blueprint process, 6,124 Blue proteins model studies, 6,653 Boleite... 

Copper proteins, 1,168 5,720 models, 2,85 nonblue, 5,723 type 111, 5,724 Copper salts cellulose dyes, 6,38 Copper(I) salts stabilization, 6,786 Copper(II) salts ammoniacal leaching, 6,787 oxidant... 

Ruggiero, C.E., Carrier, S.M. and Tolman W.B. (1994) Reductive disproportionation of NO mediated by copper complexes Modeling N20 generation by copper proteins and heterogeneous catalysts, Angew. Chem. Int. Ed., 33, 895. 

Tolman W.B. (1995) Synthetic Modeling of the Interactions of Nitrogen Oxides with Copper Proteins Copper Nitrosyl Complexes Relevant to Putative Denitrification Intermediates, Adv. Chem. Ser., 246, 195. 

From the standpoint of modeling Type I copper proteins,4,5,59,60 a variety of imidazole-based ligands containing thioether sulfurs and imidazole groups have been synthesized.61,62 The structures and spectroscopic properties of their copper(II) complexes (51)-(53) and (55)-(60) were investigated.65,79-82 To characterize apical copper(II)-thioether bonding, the complex (51) was... 

In their pursuit of modeling Type I copper proteins, Kitajima et al. reported112 a rare, tetrahedrally coordinated complex (105), which displayed an EPR spectrum consistent with the presence of the unpaired electron in the dz2 orbital.1 They also isolated a square-pyramidal DMF adduct (complex (106)). They were successful in providing structural proof of a copper(II) complex (trigonal pyramidal) with C6F5S -coordinated complex (107), with CuN3S chromo-phore.113 The X-ray analysis (poor data set) of a closely similar complex with Ph3CS as the... 

Malmstrom, B.G., and Vanngard, T. 1960. Electron spin resonance of copper proteins and some model complexes. Journal of Molecular Biology 2 118-124. 

Model systems for Type I copper proteins structures of copper coordination compounds with thioether and azole-containing ligands.17... 

This discussion of copper-containing enzymes has focused on structure and function information for Type I blue copper proteins azurin and plastocyanin, Type III hemocyanin, and Type II superoxide dismutase s structure and mechanism of activity. Information on spectral properties for some metalloproteins and their model compounds has been included in Tables 5.2, 5.3, and 5.7. One model system for Type I copper proteins39 and one for Type II centers40 have been discussed. Many others can be found in the literature. A more complete discussion, including mechanistic detail, about hemocyanin and tyrosinase model systems has been included. Models for the blue copper oxidases laccase and ascorbate oxidases have not been discussed. Students are referred to the references listed in the reference section for discussion of some other model systems. Many more are to be found in literature searches.50... 

The reaction of binuclear copper complexes with oxygen as models for tyrosinase activity was also markedly accelerated by applying pressure (106408 ). Tyrosinase is a dinuclear copper protein which catalyses the hydroxylation of phenols. This reaction was first successfully modeled by Karlin and co-workers (109), who found that an intramolecular hydroxylation occurred when the binuclear Cu(I) complex of XYL-H was treated with oxygen (Scheme 5). 

Our earlier research on the coupled binuclear copper proteins generated a series of protein derivatives in which the active site was systematically varied and subjected to a variety of spectroscopic probes. These studies developed a Spectroscopically Effective Model for the oxyhemocyanin active slte.(l) The coupled binuclear copper active site in tyrosinase was farther shown to be extremely similar to that of the hemocyanlns with differences in reactivity correlating to active site accessibility, and to the monophenol coordinating directly to the copper(II) of the oxytyroslnase site.(2) These studies have been presented in a number of reviews.(3) In the first part of this chapter, we summarize some of our more recent results related to the unique spectral features of oxyhemocyanin, and use... 

---