Crystal Structures of Two Isozymes of Citrate Synthase from Sulfolobus tokodaii Strain 7

Figure 8

(c) Ion pairs and networks at the molecular surface. (a) Ion pairs near core helices G and M in ST1805-CS. (b) Ion pairs between core helices G and M in ST0587-CS. (c) Extensive ion pair networks found on the surface perpendicular to the axis of the central helix bundle of ST0587-CS. The view is opposite side to that of Figure 2. The residues involved in the ion pairs were drawn as a ball-and-stick model. Polypeptide chains are represented as a ribbon model. Carbon, oxygen, and nitrogen atoms are shown in black, red, and blue, respectively. Hydrogen bonds are indicated as a dotted line.

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