Fig. 3

Molecular model of OXA-205 based on OXA-46 quaternary structure. D201, R210 and E238 residues forms H-bonds between different subunits in OXA-46 while D201Y substitution in OXA-205 model fails to make H-bonds with R214 residue in different subunit. Substitution also introduces clashes (data not shown). Blue and purple colors of cartoon ribbons denotes different subunits. Aforementioned residues (along with E89, N186, R197 and β7 strand strand in C-terminal end) are thought to be responsible for the formation of dimeric structure in divalent metal ions independent way [23, 29]. GMQE and QMEAN4 values of the model are 0.71 and −2.13, respectively. Model was created using SWISS-MODEL tool [20, 21] (OXA-46 assembly No. 2 from Protein data bank in Europe (PDB:3IF6) was used as a template) and visualized with the open source software PyMol (v.1.7.1.2)