Monoclinic ( P 2 1 ) polymorph β In the pH range 6.73–7.94 (Series 1) or 6.70–8.10 (Series 2) the crystals obtained belonged to the monoclinic symmetry P 2 1 [referre... to as P 2 1(β) , unit-cell parameters a = 62.8231 (7), b = 62.1078 (5), c = 47.8362 (6) Å, β = 111.6913 (9)°], a previously characterized polymorph (Derewenda et al. , 1989 ▸ ; Smith et al. , 2000 ▸ ; PDB entry 1evr ).
Figure 14 Models of the unit-cell contents for the known C 2 (PDB entry 2olz , left) and P 2 1(β) (PDB entry 1evr , right) polymorphs.