Fig. 4. rEmi2 requires divalent metal ions such as Mg ²⁺ and Co ²⁺ for the glucose phosphorylation activity.

　The specific activity of rEmi2 for glucose phosphorylation in the presence of either of metal ions, Mg ²⁺ , Co ²⁺ , Mn ²⁺ , Zn ²⁺ , or Ca ²⁺ . None , metal ions were replaced by EDTA at 2 mM. Values were normalized to that of Mg ²⁺ as 100 %. The assay was repeated twice and the average of relative specific activities are indicated.