Figure 2
Binding sites of calcium (a) and sodium (b) ions in EF-EG2 structure. The green and purple contours show the Fo - Fc (7.0[sigma]) map calculated without calcium and sodium ions, respectively. Each binding site is composed of eight and six oxygen atoms chelating to a calcium and sodium ion with distances of 2.3-2.5 and 2.3-2.7 Å (represented by black dashed lines), respectively.  [article HTML]