Figure 3. Predicted 3-D structures of nrdB^L1 (long form) and nrdB^S1 (short form) of ribonucleotide reductase β-subunit.

(a) nrdB^L and (b) nrdB^S. The iron binding residues in pink centered by a purple dot (binding site), the tyrosyl radical in red, the putative radical transfer pathway in green. The regions targeted by primer set RNRf/RNRr were highlight in cyan. All conserved residues and model was generated using Phyre server²⁹. The final refinement of all 3-D structure figures were made using the Pymol Molecular Graphics System (v1.7.6).