Table 1 CryoEM data collection, processing, model building, and validation statistics

From: A proteolytic AAA+ machine poised to unfold protein substrates

Sample and data deposition information

Sample name

ClpX∆N•ClpP•branched-DHFR•MTX

ClpX∆N•ClpP•linear-DHFR•MTX

ClpX∆N•ClpP•branched-DHFR

Nucleotide added

ATP

ATP

ATP

PDB code

8V9R

9C87

9C88

EMDB ID

43081

45299

45300

Data collection and image processing

 Microscope

Titan Krios G3i

Titan Krios G2

Titan Krios G2

 Camera

Gatan K3 (counting mode)

Gatan K3 (counting mode)

Gatan K3 (counting mode)

 Magnification (nominal)

130,000 X

130,000 X

130,000 X

 Accelerating voltage (kV)

300

300

300

 Total electron dose (e-2)

51.94

47.54

47.54

 Defocus range (µm)

-0.5 to -1.8

-0.5 to -1.75

-0.5 to -1.75

 Micrographs collected

15,920

15,864

14,574

 Pixel size (Å) initial/calibrated

0.679 / 0.654

0.65

0.65

Map reconstruction

 Image processing package

cryoSPARC

 Total extracted ClpXP particles

1,005,797

355,300

434,826

 Final particle count

449,424

71,203

178,399

 Symmetry imposed

C1

C1

C1

Resolution (Å)

 0.143 GSFSC unmasked

3.3

4.4

3.3

 0.143 GSFSC spherical mask

3.1

4.1

3.0

 0.143 GSFSC tight/local mask

2.8

3.7

2.6

 3DFSC sphericity (out of 1.0)

0.986

0.931

0.972

Model composition

 Number of atoms

72,633

77,422

74,036

 Protein residues

4,955

4,943

4,733

 Ligands

ATP (3); ADP (3) Mg (4); MTX (1)

ATP (3); ADP (3) Mg (4); MTX (1)

ATP (3); ADP (3) Mg (4)

Model refinement

 Refinement package

Phenix and Coot

 

Phenix and Coot

Map-to-model cross correlation

 masked

0.81

0.75

0.81

 unmasked

0.83

0.84

0.78

 RMSD bond lengths (Å) [#>4σ]

0.003 [0]

0.002 [0]

0.002 [0]

 RMSD bond angles (°) [#>4σ]

0.666 [0]

0.653 [0]

0.501 [0]

Model validation

 MolProbity score

0.94

1.03

0.89

 Clash score

1.80

2.48

1.04

 C-beta outliers (%)

0.02

0.02

0.0

 Rotamer outliers (%)

0.0

0.0

0.003

 Ramachandran favored (%)

99.5

99.9

97.6

Q-Score [mean]

 Global / expected from resolution

0.62 / 0.61

0.47 / 0.45

0.63 / 0.65

 ClpX

0.61

0.47

0.54

 ClpPcis

0.71

0.56

0.66

 DHFR

0.60

0.22

0.72