1om4 is a 2 chain structure with sequence from Rattus norvegicus. The January 2011 RCSB PDB Molecule of the Month feature on Nitric Oxide Synthase by David Goodsell is 10.2210/rcsb_pdb/mom_2011_1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.