7JMU

Hen egg-white lysozyme with ionic liquid ethylammonium nitrate

Summary for 7JMU

• Entry DOI: 10.2210/pdb7jmu/pdb
• Descriptor: Lysozyme C, NITRATE ION (3 entities in total)
• Functional Keywords: lysozyme, ionic liquid, nitrate, hydrolase
• Biological source: Gallus gallus (Chicken)
• Total number of polymer chains: 2
• Total formula weight: 29592.40

Authors

Han, Q.,Darmanin, C.,Smith, K.,Greaves, T.,Drummond, C. (deposition date: 2020-08-02, release date: 2020-11-11, Last modification date: 2024-10-30)

Primary citation

Han, Q.,Smith, K.M.,Darmanin, C.,Ryan, T.M.,Drummond, C.J.,Greaves, T.L.
Lysozyme conformational changes with ionic liquids: Spectroscopic, small angle x-ray scattering and crystallographic study.
J Colloid Interface Sci, 585:433-443, 2021

PubMed Abstract: Solvents that support protein functionality are important for biochemical applications, and new solvents are required. Here we employ FTIR and fluorescence spectroscopies, small angle X-ray scattering (SAXS) and X-ray crystallography to understand conformational changes of lysozyme with ionic liquids (ILs) added. Spectroscopic techniques identified that the secondary structure of lysozyme was maintained at the lower IL concentrations of 1 and 5 mol%, though the Tryptophan environment was significantly altered with nitrate-based ILs present. SAXS experiments indicated that the radius of gyration of lysozyme increased with 1 mol% IL present, and then decreased with increasing IL concentrations. The tertiary structure, particularly the loop regions, changed as a function of IL concentration, and this depended on the IL type. The crystallographic structure of lysozyme with the IL of ethylammonium nitrate present confirmed the loop region was extended, and identified three specific binding sites with nitrate ions, and that the positively charged areas were IL sensitive regions. This work provides a detailed understanding of lysozyme conformational changes in the presence of ILs. This approach can be extended to other functionally-important proteins.

PubMed: 33109332
DOI: 10.1016/j.jcis.2020.10.024

Experimental method

X-RAY DIFFRACTION (1.2 Å)