title: Resurveying the Tris buffer solution: the specific interaction between tris(hydroxymethyl)aminomethane and lysozyme.
abstract: An unusual phenomenon, the specific interaction between tris(hydroxymethyl)aminomethane (Tris) and lysozyme (LZM), was demonstrated for the first time by rapid screen analysis of interactions using a quartz crystal microbalance (QCM) biosensor. This phenomenon was also observed in a surface plasmon resonance (SPR) system. Further study using high-performance affinity chromatography (HPAC) confirmed this specific interaction between LZM and immobilized Tris with an apparent dissociation constant (K(D)) of 6.7 x 10(-5)M. Molecular docking was carried out to identify possible modes of binding between LZM and Tris linked to a binding arm. The estimated binding free energy was -6.34 kcal mol(-1), corresponding to a K(D) of 2.3 x 10(-5)M, which correlated well with the experimental value. Based on the docking model, the three hydroxyl groups of Tris form intermolecular H bonds with Asp52, Glu35, and Ala107 in LZM. This study reinforces the importance of buffer selection in quantitative biochemical investigations. For a lysozyme ligand binding study, it is better to avoid using Tris when the ligands under study are weak binders.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, The Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
authors.forename: Li
authors.initials: L
authors.lastname: Quan
authors.forename: Dengguo
authors.initials: D
authors.lastname: Wei
authors.forename: Xiaolu
authors.initials: X
authors.lastname: Jiang
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhiyu
authors.initials: Z
authors.lastname: Li
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.forename: Kean
authors.initials: K
authors.lastname: Li
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.forename: Luhua
authors.initials: L
authors.lastname: Lai
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002645:Chickens; D002846:Chromatography, Affinity; D003198:Computer Simulation; D006801:Humans; D007700:Kinetics; D008958:Models, Molecular; D009113:Muramidase / Q000737:chemistry* / Q000378:metabolism; D011791:Quartz; D012996:Solutions; D020349:Surface Plasmon Resonance; D014325:Tromethamine / Q000737:chemistry* / Q000378:metabolism
chemical_list: D012996:Solutions; D014325:Tromethamine; D011791:Quartz; D009113:Muramidase