Pseudoazurin ligands

In rusticyanin and pseudoazurin, the axial Met ligand adopts a different orientation than in azurin, resulting in a stronger Cu(II)-S8 Met bond and a tetragonal distortion. The magnetic anisotropy tensor is rhombic in the Co(II)-substituted proteins, and the pseudocontact contribution to... 

Details of the position of the —600-nm peak and absorption coefficients for blue copper proteins are indicated in Table I. There are some differences in the peak position, e.g., 597 nm for plastocyanin and 625 nm for azurin (Fig. 6). These may be related to the existence of a fifth ligand in the case of azurin (S), giving rise to trigonal-bipyramidal rather than tetrahedral coordination, but the same trend is not observed with pseudoazurin (12), which also appears to have a weak Cu—O interaction. 

Table 5. Position of the copper ligands in plastocyanin, pseudoazurin, and amicyanin...

Fig. 14. Comparison of the amino acid sequences of plastocyanin (pcy), amicyanin (acy), and pseudoazurin (paz). The copper ligands are framed conserved residues are underlined. Based on Guss and Freeman 1983 [22], Ryden and Hunt 1993 [71], and Durley et al. 1994 [78]...

C-Terminal Ligand-Containing Loop of Paracoccus uersutus Amicyanin, Poplar Plastocyanin, Alcaligenes faecalis S-6 Pseudoazurin, and Pseudomonas aeruginosa Azurin... 

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