PMID: 15106972 , Related PDB ids: 1UFJ, 1UFP

Authors:

Ueno T, Ohashi M, Kono M, Kondo K, Suzuki A, Yamane T, Watanabe Y

Title:

Crystal structures of artificial metalloproteins: tight binding of FeIII(Schiff-Base) by mutation of Ala71 to Gly in apo-myoglobin.

Journal:

Inorg Chem. 2004 May 3;43(9):2852-8.

Abstract:

Apo-myoglobin (apo-Mb) and apo-A71GMb were successfully reconstituted with FeIII(salophen) (1) (salophen = N,N'-bis(salicylidene)-1,2-phenilenediamine), Fe(III)(3,3'-Me2-salophen) (2), and FeIII(5,5'-t-Bu2-salophen) (3). The crystal structure of 2.apo-A71GMb shows the tight binding of the complex in the Mb cavity, while in wild-type apo-Mb it is highly disordered due to the steric repulsion with Ala71. Furthermore, the structure of 2.apo-A71GMb suggests a possible accommodation of a small substrate in the cavity. In fact, the cyanide association rate constant of 2.apo-A71GMb is 216-fold larger compared to that of 2.apo-Mb. These results provide us principles for the noncovalent fixation of synthetic metal cofactors at the desired positions in protein matrixes.