Rational design of a conformation-switchable Ca2+- and Tb3+-binding protein without the use of multiple coupled metal-binding sites.

ABSTRACT: Ca2+, as a messenger of signal transduction, regulates numerous target molecules via Ca2+-induced conformational changes. Investigation into the determinants for Ca2+-induced conformational change is often impeded by cooperativity between multiple metal-binding sites or protein oligomerization in naturally occurring proteins. To dissect the relative contributions of key determinants for Ca2+-dependent conformational changes, we report the design of a single-site Ca2+-binding protein (CD2.trigger) created by altering charged residues at an electrostatically sensitive location on the surface of the host protein rat Cluster of Differentiation 2 (CD2).CD2.trigger binds to Tb3+ and Ca2+ with dissociation constants of 0.3 +/- 0.1 and 90 +/- 25 microM, respectively. This protein is largely unfold

SUBMITTER: Li S 

PROVIDER: S-EPMC2613763 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature