BIOMOLECULE: 1 THIS ENTRY CONTAINS THE CRYSTALLOGRAPHIC ASYMMETRIC UNIT WHICH CONSISTS OF 3 CHAIN(S) ...BIOMOLECULE: 1 THIS ENTRY CONTAINS THE CRYSTALLOGRAPHIC ASYMMETRIC UNIT WHICH CONSISTS OF 3 CHAIN(S). SEE REMARK 350 FOR INFORMATION ON GENERATING THE BIOLOGICAL MOLECULE(S). THE POLYPEPTIDE CHAIN CONTAINS FOUR (4) COPIES OF THE TRAP PROTEIN LINKED IN TANDEM, WHICH ARRANGE THEMSELVES TO MAKE A 12-MER RING IN SOLUTION. THIS RING IS ALIGNED WITH THE CRYSTALLOGRAPHIC FOUR-FOLD AXIS, SO THAT ONLY THREE COPIES OF TRAP ARE PRESENT IN THE ASYMMETRIC UNIT. EACH COPY REPRESENTS A SYMMETRY AVERAGE. THE LINKER PEPTIDES ARE NOT VISIBLE IN THE ELECTRON DENSITY.