TABLE 1

X-ray data collection and refinement statistics

Values for the highest resolution shell are in parentheses.

Crystal
    Space GroupC121
    Unit Cell
        a89.57 Å
        b55.74 Å
        c99.09 Å
        α = γ90°
        β96.51°
Data collection
    X-ray sourceSSRL BL 11-1
    Wavelength0.98 Å
    Resolution range49.32 Å (2.00)
    Total observations223,616
    Unique observations32,536
    Completeness98.3% (88.1)
    Redundancy6.9 (4.1)
    I/σ4.6 (1.4)
    Rmergea13.1% (48.7)
Refinement statistics
    R factorb17.8%
    Rfreeb22.8%
    RMSD
        Bond lengths0.018 Å
        Bond angles1.767°
    Ramachandran plot
        Preferred98.1%
        Allowed1.5%
    No. of atoms
        Protein3791
        Heme43
        4-CPI12
        Cymal-522
        Thiocyanate12
        Water176
  • SSRL BL 11-1, beamline 11-1 of the Stanford Synchrotron Radiation Lightsource.

  • a Rmerge = [ΣhΣi|Ih-Ihi|/ΣhΣiIhi] where Ih is the mean of Ihi observations of reflection h.

  • b R factor & Rfree = Σ‖Fobs|-|Fcalc‖/Σ|Fobs| × 100 for 95% of the recorded data (R factor) and 5% of data (Rfree).