Cabaniss S E, Pugh K C, Pedersen L G, Hiskey R G
Department of Chemistry, University of North Carolina, Chapel Hill.
Int J Pept Protein Res. 1991 Jan;37(1):33-8. doi: 10.1111/j.1399-3011.1991.tb00730.x.
gamma-Carboxyglutamic acid (Gla) is believed to bind Ca [II] ions and Mg [II] ions in prothrombin and other coagulation proteins. Binding constants for H+, Ca [II] ions, and Mg [II] ions to Gla-containing peptides are determined using pH and ion selective electrode titrations. The binding constants for peptides containing a single Gla residue are similar to the constants for malonic acid. Peptides containing two Gla residues in sequence (di-Gla peptides) bind Ca [II] ions and Mg [II] ions more strongly. KMgL for the di-Gla peptides is similar to the site-binding constant for Ca [II] ions in denatured BF1. These di-Gla peptides may be useful analogs for metal binding by the disordered Gla domain in BF1.
γ-羧基谷氨酸（Gla）被认为能在凝血酶原和其他凝血蛋白中结合钙离子（Ca[II]）和镁离子（Mg[II]）。通过pH和离子选择性电极滴定法测定氢离子（H+）、钙离子（Ca[II]）和镁离子（Mg[II]）与含Gla肽段的结合常数。含单个Gla残基的肽段的结合常数与丙二酸的常数相似。序列中含两个Gla残基的肽段（双Gla肽段）能更强烈地结合钙离子（Ca[II]）和镁离子（Mg[II]）。双Gla肽段的KMgL与变性BF1中钙离子（Ca[II]）的位点结合常数相似。这些双Gla肽段可能是BF1中无序Gla结构域金属结合的有用类似物。
