Separation of basic drug enantiomers by capillary electrophoresis using chicken alpha1-acid glycoprotein: insight into chiral recognition mechanism.
Recombinant chicken alpha(1)-acid glycoprotein (alpha(1)-AGP) was prepared by the Escherichia coli expression system and completely deglycosylated alpha(1)-AGP (cd-alpha(1)-AGP) was obtained by treatments of native alpha(1)-AGP with a mixture of endoglycosidase and N-glycosidase. The average molecular masses of chicken alpha(1)-AGP, cd-alpha(1)-AGP and recombinant alpha(1)-AGP were estimated to be about 29 200, 21 700 and 20 700, respectively, by matrix-assisted laser desorption-time of flight-mass spectrometry. We compared the chiral recognition ability of chicken alpha(1)-AGP, cd-alpha(1)-AGP and recombinant alpha(1)-AGP using them as chiral selectors in capillary electrophoresis. The chicken alpha(1)-AGP showed higher resolution for eperisone, pindolol and tolperisone than cd-alpha(1)-AGP or recombinant alpha(1)-AGP. Recombinant alpha(1)-AGP still showed chiral recognition for three basic drugs tested. By addition of propranolol as a competitor in the separation solution in CE, no enantioseparations of three basic drugs were observed with chicken alpha(1)-AGP, cd-alpha(1)-AGP or recombinant alpha(1)-AGP. These results reveal that the protein domain of the chicken alpha(1)-AGP is responsible for the chiral recognition ability, and that the chiral recognition site(s) for basic drugs exists on the protein domain.
Matsunaga
Hisami
H
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, 11-68 Koshien Kyuban-cho, Nishinomiya, Hyogo 663-8179, Japan.
Sadakane
Yutaka
Y
Haginaka
Jun
J
D000818:Animals; D002645:Chickens; D003505:Cyclodextrins / Q000737:chemistry; D004527:Egg Proteins; D019075:Electrophoresis, Capillary / Q000379:methods*; D009961:Orosomucoid / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000302:isolation & purification*; D010869:Pindolol / Q000302:isolation & purification; D011427:Propiophenones / Q000302:isolation & purification; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D013237:Stereoisomerism; D014049:Tolperisone / Q000302:isolation & purification
D003505:Cyclodextrins; D004527:Egg Proteins; D009961:Orosomucoid; D004364:Pharmaceutical Preparations; D011427:Propiophenones; D011994:Recombinant Proteins; C030848:eperisone; D010869:Pindolol; D014049:Tolperisone