Procedure for the fractionation of proteins by using sequential ion exchange and hydrophobic interaction chromatography as prefractionation steps before analysis by two dimensional electrophoresis
AssigneeGuild Associates, Inc.
InventorAugustine DiNovo
Life of this patent
Estimating the term…
Abstract
After the sequencing of the human genome, great interest has developed in trying to discern the complementary proteome of humans and other species. The present disclosure provides devices, systems, and methods for proteomic fractionation that may increase the number of protein spots visualized by 2DE analysis, and may allow enrichment of proteins normally not detectable by standard 2DE analysis. According to some embodiments of the disclosure, devices, systems, and methods of the disclosure relate to fractionating a proteome on the basis of surface charge, hydrophobicity, isoelectric point and/or size.
Claims19
A method of proteomic protein fractionation comprising:
- a) applying a protein mixture to an anion exchange column;
- b) collecting a first fraction comprising the nonbinding protein flowthrough that passes through the anion exchange column;
- c) eluting the anion exchange column with a high salt buffer to form an anion exchange eluate wherein the high salt buffer comprises 0.5 M salt or greater;
- d) applying the anion exchange eluate to a hydrophobic interaction chromatography column;
- e) collecting a second fraction comprising the nonbinding protein flowthrough that passes through the hydrophobic interaction chromatography column;
- f) eluting the hydrophobic interaction chromatography column with a low salt buffer, wherein the low salt buffer comprises 0.1 M salt or less, to form a low salt eluate;
- g) collecting a third fraction comprising the low salt eluate eluted from the hydrophobic interaction chromatography column;
- h) fractionating the first fraction by two-dimensional electrophoresis comprising isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a first gel;
- i) fractionating the second fraction by two-dimensional electrophoresis comprising isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a second gel;
- and
- j) fractionating the third fraction by two-dimensional electrophoresis comprising isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a third gel,
- thereby generating more than 2 times the number of protein spots on the combination of the first gel, the second gel and the third gel, as compared to the number of spots on a single gel from a sample of the protein mixture that is not prefractionated by the anion exchange column and/or the hydrophobic interaction chromatography column, but is fractionated by two-dimensional electrophoresis comprising isoelectric focusing and polyacrylamide electrophoresis.
A method of proteomic protein fractionation comprising:
- a) applying a protein mixture comprising up to every protein in an organism's proteome to an anion exchange column;
- b) collecting a first fraction comprising the nonbinding protein flowthrough that passes through the anion exchange column;
- c) eluting the anion exchange column with a high salt buffer, wherein the high salt buffer comprises 0.5 M salt or greater without a gradient, to form an anion exchange eluate;
- d) applying the anion exchange eluate to a hydrophobic interaction chromatography column;
- e) collecting a second fraction comprising the nonbinding protein flowthrough that passes through the hydrophobic interaction chromatography column;
- f) eluting the hydrophobic interaction chromatography column with a low salt buffer, wherein the low salt buffer comprises 0.1 M salt or less without a gradient, to form a low salt eluate;
- g) collecting a third fraction comprising the low salt eluate eluted from the hydrophobic interaction chromatography column;
- h) optionally eluting the hydrophobic interaction chromatography column with a low salt buffer comprising an organic solvent to form a fourth fraction comprising a low salt plus solvent eluate;
- i) fractionating the first fraction by two-dimensional electrophoresis comprising isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a first gel;
- j) fractionating the second fraction by isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a second gel;
- k) fractionating the third fraction comprising the low salt eluate by isoelectric focusing and sodium dodecyl sulfate polyacrylamide electrophoresis on a third gel, and
- l) optionally fractionating the fourth fraction comprising the low salt plus solvent eluate by isoelectric focusing and polyacrylamide electrophoresis on a fourth gel;
- thereby generating more than 2 times the number of protein spots on the combination of the first, second and third gels, or the combination of the first, second, third and fourth gels, as compared to the number of spots on a single gel from a sample of the protein mixture that is not prefractionated by the anion exchange column and/or the hydrophobic interaction chromatography column, but is fractionated on a single gel by two-dimensional electrophoresis comprising isoelectric focusing and polyacrylamide electrophoresis.
Dependencies are inferred from the claim text.