1REQ

METHYLMALONYL-COA MUTASE

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1				THE CRYSTALS WERE GROWN IN THE PRESENCE OF 2MM EXCESS 5'-DEOXYADENOSYLCOBALAMIN (COENZYME B12) AND 12MM DESULPHO-COA (FINAL CONCENTRATIONS), EQUILIBRATED AGAINST 14% W/V PEG 4000 AND 20% V/V GLYCEROL, 100MM TRIS PH 7.5. THE ELECTRON DENSITY MAPS SHOW NO ADENOSYL GROUP ATTACHED TO THE COBALT ATOM, AND SPECTRA FROM SIMILAR CRYSTALS SHOW EVIDENCE OF SUBSTANTIAL REDUCTION OF COIII TO COII, WHICH IS 5-COORDINATE. THE COBALAMIN IN THIS CRYSTAL STRUCTURE IS BEST CONSIDERED AS REDUCED COB(II)ALAMIN (OR B12R). THE BOND LENGTH FROM THE COBALT TO THE LOWER AXIAL LIGAND, NE2 OF HIS A 610 (OR HIS C 610) IS SIGNIFICANTLY LONGER THAN THAT IN MODEL COMPOUNDS. POORLY ORDERED LOOPS: DENSITY IN THE FOLLOWING REGIONS IS POOR, AND THE MODEL MUST BE CONSIDERED UNRELIABLE. ALPHA CHAIN: A 1, C 1 MISSING, A 2 - A 3, C 2 - C 3 WEAK. BETA CHAIN: B 1 - C 19, C 1 - C 16 MISSING; B 184 - B 191, D 184 - D 191 WEAK; D 228 - D 230 WEAK; D 271 - D 276 VERY POOR DENSITY (MUCH BETTER IN CHAIN B); D 315 WEAK; D 474 - D 428 WEAK.

Crystal Properties
Matthews coefficient	Solvent content
2.76	48

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 119.8	α = 90
b = 161.3	β = 105.1
c = 88.4	γ = 90

Symmetry
Space Group	P 1 21 1

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray		IMAGE PLATE	MAR scanner 300 mm plate		1994-06-24	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	ESRF BEAMLINE ID2		ESRF	ID2

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	Net I Over Average Sigma (I)	Redundancy	Number Reflections (All)	Number Reflections (Observed)	Observed Criterion Sigma (F)	Observed Criterion Sigma (I)	B (Isotropic) From Wilson Plot
1	2	20	99.8	0.051		4.6		217377		5

Refinement

Statistics
Diffraction ID	Structure Solution Method	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION		2	20	206327	10907	99.8	0.22	0.275	42

Temperature Factor Modeling
Anisotropic B[1][1]	Anisotropic B[1][2]	Anisotropic B[1][3]	Anisotropic B[2][2]	Anisotropic B[2][3]	Anisotropic B[3][3]

RMS Deviations
Key	Refinement Restraint Deviation
p_scangle_it	5.8
p_scbond_it	4.6
p_mcangle_it	4.1
p_mcbond_it	3.2
p_multtor_nbd	0.256
p_xyhbond_nbd	0.187
p_singtor_nbd	0.183
p_chiral_restr	0.156
p_planar_d	0.044
p_angle_d	0.039
p_bond_d	0.017
p_plane_restr	0.013
p_angle_deg
p_hb_or_metal_coord
p_xhyhbond_nbd
p_planar_tor
p_staggered_tor
p_orthonormal_tor
p_transverse_tor
p_special_tor

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	20510
Nucleic Acid Atoms
Solvent Atoms	1532
Heterogen Atoms	330

Software

Software
Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction