title: Affinity and hydrophobic chromatography of Escherichia coli aspartate transcarbamoylase.
abstract: Chromatography of aspartate transcarbamoylase from Escherichia coli on agarose-immobilized dyes and alkyl-agaroses of differing carbon length were investigated. The bacterial aspartate transcarbamoylase was bound by Procoin red HE3B-agarose and Cibacron blue F3GA-agarose nearly completely under the conditions chosen relative to other agarose-coupled dyes. The aspartate transcarbamoylase holoenzyme was eluted from the Procion red HE3B-agarose slightly later than from the Cibacron blue F3GA-agarose during salt gradient elution. The catalytic trimer of the enzyme as well as its regulatory dimer were eluted by a lower salt concentration from both dye-agarose gels than the concentration required to elute the holoenzyme. The interaction of the catalytic trimer with the Procion red HE3B-agarose and Cibacron blue F3GA-agarose gels may be a determinant in the holoenzyme being retained on these resins. Of those alkyl-agaroses tested, the ethyl-, propyl- and hexyl-agarose gels bound the majority of aspartate transcarbamoylase activity. Chromatography of aspartate transcarbamoylase on ethyl-agarose found it to be eluted by a low salt concentration. A purification scheme for relatively small amounts of aspartate transcarbamoylase utilizing Procion red HE3B-agarose and ethyl-agarose is presented. This purification scheme is particularly useful for mutant versions of aspartate transcarbamoylase which cannot be purified by literature procedures.
mesh_terms: D001221:Aspartate Carbamoyltransferase / Q000302:isolation & purification*; D002846:Chromatography, Affinity; D004926:Escherichia coli / Q000201:enzymology*; D012685:Sepharose; D014227:Triazines
chemical_list: D014227:Triazines; C012842:Cibacron Blue F 3GA; C020795:procion red HE-3B; D012685:Sepharose; D001221:Aspartate Carbamoyltransferase