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Lecture 3: Working with proteins + Detection and purification

Terms in this set (40)

Why do the biggest proteins move fast in size exclusion chromatography and slowly in SDS gel electrophoresis? (SDS = sodium dodecyl sulphate)
a. In size exclusion chromatography, polyacrylamide is crosslinked, with two different monomers, through copolymerization. The pore size is dependent on the degree of crosslinking monomers. Small proteins cannot enter the space/cavities of the cross-linked polymer, and therefore they go off the column faster than lager proteins.In SDS electrophoresis, polymerized polyacrylamide is formed by polymerization of acrylamide monomers. The final polymerized polyacrylamide matrix comprises a three-dimensional network of pores whose size is regulated by the percentage degree of acrylamide monomer and cross-linker concentration in the polymerizing mixture. The molecular size of the pores is comparable to the size of protein molecules. Thus, the proteins are sieved through the pores with smaller proteins having a slower migration than the lager proteins.
b. In size exclusion chromatography, polymerized polyacrylamide is formed by polymerization of acrylamide monomers. The final polymerized polyacrylamide matrix comprises a three-dimensional network of pores whose size is regulated by the percentage degree of acrylamide monomer and cross-linker concentration in the polymerizing mixture. The molecular size of the pores is comparable to the size of protein molecules. Thus, the proteins are sieved through the pores with smaller proteins having a slower migration than the lager proteins.In SDS electrophoresis, polyacrylamide is crosslinked, with two different monomers, through copolymerization. The pore size is dependent on the degree of crosslinking monomers. Small proteins cannot enter the space/cavities of the cross-linked polymer, and therefore they go off the column faster than lager proteins.
c. In size exclusion chromatography, polyacrylamide is crosslinked, with two different monomers, through copolymerization. The pore size is dependent on the degree of crosslinking monomers. Large proteins cannot enter the space/cavities of the cross-linked polymer, and therefore they go off the column faster than smaller proteins.In SDS electrophoresis, polymerized polyacrylamide is formed by polymerization of acrylamide monomers. The final polymerized polyacrylamide matrix comprises a three-dimensional network of pores whose size is regulated by the percentage degree of acrylamide monomer and cross-linker concentration in the polymerizing mixture. The molecular size of the pores is comparable to the size of protein molecules. Thus, the proteins are sieved through the pores with large proteins having a slower migration than the smaller proteins.
d. In size exclusion chromatography, polymerized polyacrylamide is formed by polymerization of acrylamide monomers. The final polymerized polyacrylamide matrix comprises a three-dimensional network of pores whose size is regulated by the percentage degree of acrylamide monomer and cross-linker concentration in the polymerizing mixture. The molecular size of the pores is comparable to the size of protein molecules. Thus, the proteins are sieved through the pores with large proteins having a slower migration than the smaller proteins.In SDS electrophoresis, polyacrylamide is crosslinked, with two different monomers, through copolymerization. The pore size is dependent on the degree of crosslinking monomers. Large proteins cannot enter the space/cavities of the cross-linked polymer, and therefore they go off the column faster than smaller proteins.