Study of competitive binding of enantiomers to protein by affinity capillary electrochromatography.
Affinity capillary electrochromatography (CEC) with zonal elution method was used to probe the competitive interactions of enantiomers with protein. In this approach, a known concentration of a competing agent is continuously applied to a CEC column with bovine serum albumin (BSA) physically adsorbed on SAX packing while injections of a small amount of analyte are made. The binding sites of solutes on the BSA molecule were determined by the changes in the retention factors of the solutes resulted from the addition of competitive agent. By using D- or L-tryptophan as competitive agents and D-, L-tryptophan and benzoin enantiomers as injected analytes showed that BSA molecule has a primary site to strongly bind L-tryptophan, but D-tryptophan dose not bind at this site; D- and L-tryptophan share a weak binding site on the BSA molecule. Benzoin enantiomers do not share any binding sites with either D- or L-tryptophan. Non-chiral compounds of trichloroacetic acid and n-hexanoic acid were applied as the competitive agents to study the binding of warfarin enantiomers to BSA, it was observed that trichloroacetic acid and n-hexanoic acid had a same binding site for warfarin enantiomers binding to BSA molecule.
Ye
Mingliang
M
National Chromatographic R&A Center, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116011, China.
Zou
Hanfa
H
Liu
Zhen
Z
Wu
Renan
R
Lei
Zhengdeng
Z
Ni
Jianyi
J
D001667:Binding, Competitive; D002846:Chromatography, Affinity / Q000379:methods; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000378:metabolism*; D011485:Protein Binding; D012710:Serum Albumin, Bovine / Q000032:analysis / Q000378:metabolism; D013237:Stereoisomerism; D014364:Tryptophan / Q000032:analysis / Q000378:metabolism
D004364:Pharmaceutical Preparations; D012710:Serum Albumin, Bovine; D014364:Tryptophan