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Figure 6
(a) The coordination group Ca DDDOE 2 2 2 5 in 2pvb_A 90. This is typical of Ca coordination groups in EF-hand proteins. (b) The coordination group HHE 4 20 in 1ezm_ 140. Zn is coordinated by three donor groups from the protein and by a water molecule. The donor amino acids belong to two helices. The protein is a hydrolase. (c) The protein chain of 1rmd of residues 1–70 and the three zinc coordination groups associated with it. The first group, CHCH, coordinates to Zn through residues 2, 6, 29 and 31, the second group, CCCC, through residues 26, 29, 46 and 49, and the third, CHCC, through 41, 43, 61 and 64. Note that these groups overlap. The sharing of a cysteine S between the first and second groups brings these two Zn atoms to 3.9 Å. The long chelate loops of the first and third coordination groups are shown in a slightly different shade of green. A fourth Zn is coordinated through residues 91, 96, 108 and 112, but is remote from any of the first three and is not shown here. (All figures prepared in the same way as Fig. 3 ![]() |