Table 1.

Data collection and refinement statistics

	NMN	5′-AMP	3′-AMP	2′-AMP	phosphate
Beamline	24-ID-C	4.2.2	4.2.2	4.2.2	24-ID-C
Wavelength	0.9792	1.00	1.00	1.00	0.9792
Data collection resolution (Å)	50 – 1.35 (1.40 – 1.35)	50 – 1.55 (1.61–1.55)	50 – 1.85 (1.92 – 1.85)	50 – 1.90 (1.93 – 1.90)	50 – 1.40 (1.45 – 1.40)
No. of observations	622380	944628	536096	499757	340873
No. of unique reflections	66003	44418	26166	24575	57486
Rmerge(I)	0.074 (0.603)	0.088 (0.427)	0.114 (0.439)	0.120 (0.534)	0.064 (0.557)
Average I/σ	39.6 (4.3)	47.0 (5.9)	27.6 (4.35)	30.2 (3.47)	25.4 (2.8)
Completeness (%)	99.7 (100)	100 (100)	99.9 (99.4)	99.9 (98.3)	95.9 (98.3)
Redundancy	9.4 (9.4)	21.3 (19.0)	20.5 (14.3)	20.3 (13.0)	5.9 (5.4)
Refinement resolution (Å)	50 – 1.35 (1.37 – 1.35)	50 – 1.55 (1.58–1.55)	50 – 1.85 (1.92 – 1.85)	50 – 1.90 (1.98 – 1.90)	50 – 1.40 (1.42 – 1.40)
Rcryst	0.135 (0.211)	0.141 (0.159)	0.164 (0.177)	0.178 (0.196)	0.139 (0.207)
Rfreea	0.154 (0.245)	0.171 (0.219)	0.189 (0.202)	0.217 (0.245)	0.168 (0.277)
No. of protein residues	247	247	247	247	247
No. of protein atoms	1933	1938	1931	1912	1929
No. of water molecules	274	280	231	173	256
Average B-factor (Å2)
Protein	14.1	15.8	16.8	26.8	14.2
Water	25.0	27.5	24.4	30.4	24.9
Ligand	12.2	15.7	22.1	23.3	11.7
Mg+2	7.7	9.7	11.8	15.8	7.6
rmsdb
Bonds (Å)	0.006	0.005	0.006	0.006	0.005
Angles (deg)	1.17	1.04	1.00	1.02	1.03
Ramachandran plotc
Favored (%)	98.0	98.0	98.0	97.5	98.0
Allowed (%)	2.0	2.0	2.0	2.5	2.0
Coordinate error (Å)d	0.13	0.17	0.18	0.21	0.14
PDB code	3OCU	3OCV	3OCW	3OCX	3OCY

Values for the outer resolution shell of data are given in parenthesis.

^aA common set of test reflections (5 %) was used for refinement of all structures.

^bCompared to the parameters of Engh and Huber.³⁷

^cThe Ramachandran plot was generated with RAMPAGE.³⁸

^dMaximum likelihood-based coordinate error estimate.