title: Subunit structure of the methionine-repressible aspartokinase II--homoserine dehydrogenase II from Escherichia coli K12.
abstract: The quaternary structure of Escherichia coli K12 aspartokinase II--homoserine dehydrogenase II has been examined. This multifunctional protein has a molecular weight Mr = 176000. It is composed of two subunits having the same molecular weight and the same charge. The results obtained from the examination of tryptic maps, the number and amino acid composition of cysteine-containing peptides and the uniqueness of the N-terminal sequence, strongly suggest that the 2 subunits are identical. The properties of aspartokinase II--homoserine dehydrogenase II can be compared to those of the much better known protein aspartokinase I--homoserine dehydrogenase I.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001225:Aspartokinase Homoserine Dehydrogenase; D055598:Chemical Phenomena; D002621:Chemistry; D004794:Enzyme Repression; D004926:Escherichia coli / Q000201:enzymology*; D046911:Macromolecular Substances; D008715:Methionine / Q000494:pharmacology; D008970:Molecular Weight; D009097:Multienzyme Complexes; D010446:Peptide Fragments / Q000032:analysis; D014357:Trypsin
chemical_list: D000596:Amino Acids; D046911:Macromolecular Substances; D009097:Multienzyme Complexes; D010446:Peptide Fragments; D008715:Methionine; D001225:Aspartokinase Homoserine Dehydrogenase; D014357:Trypsin