Table 1.

R‐Factor Ratios of Selective Protein Entries from the PDB^a

PDB accession	Description	Resolution (Å)	R Ratio	R work (%)	R free (%)	H2O: residue ratiob
5BV2	E. coil C2 catalase	1.53	1.22	8.2	13.2	1.48
5BV2/dry	E. coil C2 catalase	1.53	3.46	18.8	22.9	0.00
3P9Q	E. coli P21 catalase	1.48	2.11	14.3	17.8	1.20
4BFL	E. coli P21 catalase	1.64	3.04	17.4	20.2	0.66
4XOF	Human ubiquitin	1.15	2.69	13.7	17.1	1.45
4PIH	Human ubiquitin	1.50	2.95	16.5	19.0	0.91
4PIJ	Human ubiquitin	1.50	5.36	17.6	19.8	0.53
4WES	Nitrogenase	1.08	1.67	11.0	13.3	1.25
2VB1	Triclinic lysozyme	0.65	3.89	8.5	9.5	1.04
3O4P	Diisopropyl fluorophosphatase	0.85	1.58	10.3	12.1	1.58
4AYP	1,2‐α‐Mannosidase	0.85	2.32	9.6	10.6	1.78
4GHO	Ribonuclease	1.10	2.20	9.8	11.7	1.78
4MJ9	Ru‐10bp‐DNA duplex	0.97	2.96	8.6	9.6	11.6
4F19	Phosphate‐binding protein	0.95	2.41	9.6	11.1	2.17
4F1U	Phosphate‐binding protein	0.98	3.41	8.8	9.6	2.55

^aReferences for these entries are: 5BV2 (⁴), 3P9Q (⁵), 4BFL (⁶), 4XOF (⁷), 4PIH (⁸), 4PIJ (⁸), 4WES (⁹), 2VB1 (¹⁰), 3O4P (¹¹), 4AYP (¹²), 4GHO (¹³), 4MJ9 (¹⁴), 4F19 (¹⁵), and 4F1U (¹⁵). 5BV2/dry is the 5BV2 model after deleting all 4669 ordered water molecules. Either underestimation of experimental errors or the existence of modeling errors can lead to large R _Ratio values.

^bMultiple conformers of ordered water molecules and protein residues are counted independently. Note that 4MJ9 is a nucleic acid model, which has many more ordered water molecules per residue.