Fig. 2.

Stereo image of the 2-OG–binding site. Residues involved in binding of 2-OG (atoms are marked with small numbers) and the hydrophilic portion of ATP are numbered according to the sequence. Cofactors as well as side- and main-chain atoms are marked in stick representation; Mg²⁺ is marked as a green sphere. Colors of residue numbers (orange and blue) correspond to those of the respective subunits. Residues conserved in standard alignments are boxed. Dashed blue lines represent bonds between residues and ATP and black lines indicate bonds for the ligation of 2-OG, whereas green lines mark the hexagonal coordination of the Mg²⁺ ion.