4NGI

Previously de-ionized HEW lysozyme crystallized in 1.0 M RbCl and collected at 125K

Summary for 4NGI

• Entry DOI: 10.2210/pdb4ngi/pdb
• Related: 4NEB 4NFV 4NG1 4NG8 4NGI 4NGJ 4NGK 4NGL 4NGO 4NGV 4NGW 4NGY
• Descriptor: Lysozyme C, RUBIDIUM ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: hofmeister series, protein cation interactions, esi-mass spectrometry, hydrolase
• Biological source: Gallus gallus (bantam,chickens)
• Total number of polymer chains: 1
• Total formula weight: 14452.08

Authors

Benas, P.,Legrand, L.,Ries-Kautt, M. (deposition date: 2013-11-02, release date: 2014-05-28, Last modification date: 2023-09-20)

Primary citation

Benas, P.,Auzeil, N.,Legrand, L.,Brachet, F.,Regazzetti, A.,Ries-Kautt, M.
Weak protein-cationic co-ion interactions addressed by X-ray crystallography and mass spectrometry.
Acta Crystallogr.,Sect.D, 70:2217-2231, 2014

PubMed Abstract: The adsorption of Rb(+), Cs(+), Mn(2+), Co(2+) and Yb(3+) onto the positively charged hen egg-white lysozyme (HEWL) has been investigated by solving 13 X-ray structures of HEWL crystallized with their chlorides and by applying electrospray ionization mass spectrometry (ESI-MS) first to dissolved protein crystals and then to the protein in buffered salt solutions. The number of bound cations follows the order Cs(+) < Mn(2+) ≃ Co(2+) < Yb(3+) at 293 K. HEWL binds less Rb(+) (qtot = 0.7) than Cs(+) (qtot = 3.9) at 100 K. Crystal flash-cooling drastically increases the binding of Cs(+), but poorly affects that of Yb(3+), suggesting different interactions. The addition of glycerol increases the number of bound Yb(3+) cations, but only slightly increases that of Rb(+). HEWL titrations with the same chlorides, followed by ESI-MS analysis, show that only about 10% of HEWL binds Cs(+) and about 40% binds 1-2 Yb(3+) cations, while the highest binding reaches 60-70% for protein binding 1-3 Mn(2+) or Co(2+) cations. The binding sites identified by X-ray crystallography show that the monovalent Rb(+) and Cs(+) preferentially bind to carbonyl groups, whereas the multivalent Mn(2+), Co(2+) and Yb(3+) interact with carboxylic groups. This work elucidates the basis of the effect of the Hofmeister cation series on protein solubility.

PubMed: 25084340
DOI: 10.1107/S1399004714011304

Experimental method

X-RAY DIFFRACTION (1.7 Å)