Obtaining site-specific calcium-binding affinities of calmodulin.
Calmodulin (CaM) is an EF-hand Ca(II)-binding protein involved in the regulation of many important biological processes. To date, there is a wealth of information available concerning studies to obtain site-specific calcium binding affinities of CaM, and further to estimate the cooperativity of calcium binding using mutational studies, peptide models, and proteolytic fragmentation. In this paper, we will discuss the energetics of calcium binding and the strong relationship between calcium binding cooperativity and conformational change. We then explain the difficulty of studying key determinants of calcium binding affinity of CaM due to the large change of calcium binding affinity upon mutation. Subsequently, we will introduce "grafting" as a novel approach to obtain the site-specific metal binding properties of calmodulin.
Yang
Jenny J
JJ
Department of Chemistry and Center for Drug Design and Advanced Biotechnology, Georgia State University, Atlanta, GA 30303, USA. chejjy@panther.gsu.edu
Gawthrop
Amy
A
Ye
Yiming
Y
D000595:Amino Acid Sequence; D001667:Binding, Competitive; D002118:Calcium / Q000737:chemistry*; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000235:genetics; D002147:Calmodulin / Q000737:chemistry* / Q000235:genetics; D020832:EF Hand Motifs / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D015202:Protein Engineering / Q000379:methods; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship; D013816:Thermodynamics
D002135:Calcium-Binding Proteins; D002147:Calmodulin; D002118:Calcium