Table 1.

Data collection and refinement statistics

	T4 lysozyme‐MCU NTD	T4 lysozyme‐MCU NTD S92A	MCU NTD‐E
	PDB ID: 4XSJ	PDB ID: 5BZ6	PDB ID: 4XTB
Data collection
Space groupa	P65	P65	P65
X‐ray sourceb and detector	PAL‐5C ADSC Q315r	PAL‐5C ADSC Q315r	PAL‐7A ADSC Q270
Wavelength (Å)	0.9795	0.9795	0.9793
Unit cell: a, b, c (Å)	98.1, 98.1, 62.4	97.8, 97.8, 61.5	55.5, 55.5, 68.9
α, β, γ (°)	90.0, 90.0, 120.0	90.0, 90.0, 120.0	90.0, 90.0, 120.0
Resolution range (Å)c	50–1.80 (1.83–1.80)	50–2.75 (2.80–2.75)	50−1.50 (1.53−1.50)
R merge d	6.8 (54.6)	12.3 (56.3)	4.7 (51.5)
I/σI	18.2 (3.2)	6.8 (3.3)	11.9 (3.6)
Completeness (%)	99.5 (98.3)	99.5 (100.0)	99.4 (100.0)
Redundancy	8.0 (6.3)	4.7 (5.3)	5.7 (5.6)
Refinement
Resolution range (Å)c	48.5–1.80	34.9–2.75	48.0–1.50
No. reflections	29581	8147	17594
R work e (%)/R free (%)	12.7/19.0	16.4/23.5	14.0/17.6
No. atoms
Protein	2008	2007	863
Ligand	−	−	13f
Ion (${\mathrm{SO}}_4^{2-}$)	15	30	−
Water	431	41	143
B‐factors (Å2)
Protein	27.0	33.7	18.2
Ligand	−	−	30.3
Ion (${\mathrm{SO}}_4^{2-}$)	40.6	56.7	−
Water	47.4	29.9	39.5
Model statistics
rmsd bond length (Å)	0.010	0.014	0.010
rmsd bond angles (°)	1.33	1.67	1.64
Ramachandran plot (%) favoured/allowed/disallowed	98.8/1.2/0	97.2/2.8/0	99.1/0.9/0

^a P6₅‐related MCU NTD/MCU NTD interactions are conserved in these three P6₅ crystal forms.

^bBeamline 5C and 7A at Pohang Accelerator Laboratory (PAL) in South Korea.

^cValues in parentheses are for highest‐resolution shell.

^d R _merge = ∑_h ∑_i │I(h)_i−‹I(h)›│/∑_h ∑_iI(h)_i, where I(h) is the intensity of reflection of h, ∑_h is the sum over all reflections and ∑_i is the sum over i measurements of reflection h.

^e R _work = ∑_hkl ¦¦F_o¦‐¦F_c¦¦/∑_hkl¦F_o¦; 5% of the reflections were excluded for the R _free calculation.

^fAn unidentified electron density was observed and modeled with a tetraethylene glycol molecule.