The multiple nucleotide–divalent cation binding modes of Saccharomyces cerevisiae CK2α indicate a possible co-substrate hydrolysis product (ADP/GDP) release pathway

Four crystal structures of S. cerevisiae CK2α (scCK2α) with different nucleotide co-substrates and coordinated divalent cations indicated that scCK2α possesses dual co-substrate specificity, possible multiple nucleotide–divalent cation binding modes and a possible ADP/GDP-release pathway by means of conformational change of β1/G-loop/β2. The presence of a unique insertion loop in scCK2α enhanced the catalytic efficiency of the enzyme by stabilizing the open conformation of the catalytic site.

The structural basis of urea-induced protein unfolding in β-catenin

Although urea and guanidine hydrochloride are commonly used to denature proteins, the molecular underpinnings of this process have remained unclear for a century. To address this question, crystal structures of β-catenin were determined at various urea concentrations.