Mutational analysis of affinity and selectivity of kringle-tetranectin interaction. Grafting novel kringle affinity ontp the trtranectin lectin scaffold.
C-type lectin-like domains are found in many proteins, where they mediate binding to a wide diversity of compounds, including carbohydrates, lipids, and proteins. The binding of a C-type lectin-like domain to a ligand is often influenced by calcium. Recently, we have identified a site in the C-type lectin-like domain of tetranectin, involving Lys-148, Glu-150, and Asp-165, which mediates calcium-sensitive binding to plasminogen kringle 4. Here, we investigate the effect of conservative substitutions of these and a neighboring amino acid residue. Substitution of Thr-149 in tetranectin with a tyrosine residue considerably increases the affinity for plasminogen kringle 4, and, in addition, confers affinity for plasminogen kringle 2. As shown by isothermal titration calorimetry analysis, this new interaction is stronger than the binding of wild-type tetranectin to plasminogen kringle 4. This study provides further insight into molecular determinants of importance for binding selectivity and affinity of C-type lectin kringle interactions.
Graversen
J H
JH
Laboratory of Gene Expression, Department of Molecular and Structural Biology and the Department of Medical Biochemistry, University of Aarhus, DK-8000 Aarhus C, Denmark.
Jacobsen
C
C
Sigurskjold
B W
BW
Lorentsen
R H
RH
Moestrup
S K
SK
Thogersen
H C
HC
Etzerodt
M
M
D001483:Base Sequence; D001798:Blood Proteins / Q000235:genetics / Q000378:metabolism*; D004252:DNA Mutational Analysis; D017931:DNA Primers; D018082:Kringles / Q000235:genetics*; D037181:Lectins, C-Type; D016297:Mutagenesis, Site-Directed; D017510:Protein Folding; D020349:Surface Plasmon Resonance
D001798:Blood Proteins; D017931:DNA Primers; D037181:Lectins, C-Type; C048648:tetranectin