Influence of Alkylammonium Acetate Buffers on Protein-Ligand Noncovalent Interactions Using Native Mass Spectrometry.
We investigate the influence of three volatile alkylammonium acetate buffers on binding affinities for protein-ligand interactions determined by native electrospray ionization-mass spectrometry (ESI-MS). Four different types of proteins were chosen for this study. A charge-reduction effect was observed for all the cases studied, in comparison to the ions formed in ammonium acetate solution. When increasing the collision energy, the complexes of trypsin and the ligand were found to be more stable when sprayed from alkylammonium acetate buffers than from ammonium acetate. The determined dissociation constant (Kd) also exhibited a drop (up to 40%) when ammonium acetate was replaced by alkylammonium acetate buffers for the case of lysozyme and the ligand. The prospective uses of these ammonium acetate analogs in native ESI-MS are discussed in this paper as well. Graphical Abstract ᅟ.
Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093, Zurich, Switzerland.|National Center of Mass Spectrometry in Changchun, Jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.|University of Chinese Academy of Sciences, Beijing, 100039, China.
Xiaoyu
X
Zhuang
Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093, Zurich, Switzerland.
Agni F M
AFM
Gavriilidou
Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093, Zurich, Switzerland. zenobi@org.chem.ethz.ch.
Renato
R
Zenobi
D000085:Acetates / Q000737:chemistry; D002021:Buffers; D024402:Carbonic Anhydrase II / Q000737:chemistry; D002740:Chlorothiazide / Q000737:chemistry; D007782:Lactoglobulins / Q000737:chemistry; D007850:Lauric Acids / Q000737:chemistry; D008024:Ligands; D009113:Muramidase / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013450:Sulfones / Q000737:chemistry; D014357:Trypsin / Q000737:chemistry
D000085:Acetates; D002021:Buffers; D007782:Lactoglobulins; D007850:Lauric Acids; D008024:Ligands; D011506:Proteins; D013450:Sulfones; C030358:lauric acid; C002010:4-(2-aminoethyl)benzenesulfonylfluoride; D002740:Chlorothiazide; D009113:Muramidase; D014357:Trypsin; D024402:Carbonic Anhydrase II; C018824:ammonium acetate
Alkylammonium salts; Charge reduction; Native mass spectrometry; Noncovalent interactions