. Author manuscript; available in PMC: 2009 Nov 18.

Published in final edited form as: Biochemistry. 2008 Oct 25;47(46):12065–12077. doi: 10.1021/bi800894u

Table 1. Construction of cryosolution to fill lattice interstices.

Initially, the model unit cell consisted of the material observed in the crystal unit cell, 16 biotin-liganded streptavidin monomers and 1912 water molecules, plus reconstructed protein residues. The model unit cell was completed by adding solvent molecules in the order given above. The placement procedure for new solvent molecules is described in Methods: Unit cell preparation and the first section of the Supporting Information.

Molecular formula	Molar ratio in real cryosolution	Order of addition	Number of particles added	Initial value of R_solv, Å

SO₄²⁻	0.0474	1	166	8.0
NH₄⁺	0.0949	2	332	4.0
CH₃COO⁻	0.0033	3	12	4.0
Na⁺	0.0100	4	35	4.0
Cl⁻	0.0067	5	23	4.0
CH₂OHCHOHCH₂OH	0.1600	6	561	2.0
H₂O	1.0000	7	1593	1.5