Figure 2.

Ca²⁺-binding affinities and structures of different classes of Ca²⁺-binding proteins (CaBPs). (a) Ca²⁺ binds to different proteins with affinities varying from nM to mM. (b) Cartoon representation of EF-hand Ca²⁺-binding motif. (c) Trigger proteins such as calmodulin (top) with four EF-hand Ca²⁺-binding motifs undergo Ca²⁺-dependent global conformational changes upon association with target proteins. (d) Buffer proteins, such as calbindinD9K and parvalbumin, have been shown to buffer local Ca²⁺ concentration without significant conformational changes. (e) Ca²⁺ binding to thermolysin stabilizes the protein structure and confers thermal stability. http://etd.gsu.edu/theses/available/etd-11272007-155719/. It is from Dr.Yubin Zhou’s dissertation in our lab.