Comparison of the protein adsorption selectivity of salt-promoted agarose-based adsorbents. Hydrophobic, thiophilic and electron donor-acceptor adsorbents.
Protein adsorption of human serum onto six different agarose-based chromatographic gels that were representative of the salt-promoted adsorbent family [octyl- and phenyl-Sepharose, mercaptoethanol-divinyl sulfone agarose (T gel), mercaptomethylene pyridine-derivatized agarose gel (MP gel), tricyanoaminopropene-divinyl sulfone agarose (DVS-TCP gel), tricyanoamino-propene-bisoxirane agarose (bisoxirane-TCP gel)] was studied in the presence of moderate or high concentrations of the water structuring salt, sodium sulfate. Study of the protein adsorption selectivity by two-dimensional gel electrophoresis revealed an opposed selectivity for hydrophobic interaction adsorbents and electron donor-acceptor adsorbents. The T gel, MP gel and TCP gels belonged to the electron donor-acceptor adsorbents, displaying a main selectivity for immunoglobulins, whereas octyl-Sepharose belonged to the hydrophobic adsorbents, displaying a main selectivity for 'hydrophobic' proteins. Phenyl-Sepharose for its part was described as an example of a composite selectivity of both families. The conclusion of this work is two-fold: (1) hydrophobic interaction chromatography (HIC) and electron donor-acceptor chromatography (EDAC) have opposed protein selectivities and are both salt-promoted. As a main consequence, it means that high concentrations of a water-structuring salt can promote different types of weak molecular interactions, resulting in different protein adsorption selectivities: (2) thiophilic adsorption chromatography (TAC) should be renamed EDAC as similar protein selectivity is demonstrated for electron donor-acceptor ligand devoid of sulfur atoms.
Berna
P P
PP
Biochemical Separation Centre, University of Uppsala, BMC, Sweden.
Berna
N
N
Porath
J
J
Oscarsson
S
S
D000327:Adsorption; D001798:Blood Proteins / Q000032:analysis* / Q000145:classification; D002847:Chromatography, Agarose / Q000379:methods*; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D008024:Ligands; D012680:Sensitivity and Specificity; D012685:Sepharose / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry
D001798:Blood Proteins; D008024:Ligands; D013431:Sulfates; C012036:sodium sulfate; D012685:Sepharose