title: Formation of a complex between yeast proteinases A and B.
abstract: Sephadex G-100 gel filtration of a purified mixture of tryptophan-synthase-inactivating enzymes I and II from Saccharomyces cerevisiae, which had previously been identified as yeast proteinases A and B, yields two coincident peaks of tryptophan-synthase-inactivating activity and proteinase A and B activities. The peaks correspond to molecular weights of approximately 100 000 and 50 000. It could be demonstrated, with purified proteinases A and B, that the high molecular weight peaks is due to the formation of a stoichiometric complex between proteinases A and B. The AB complex can easily be separated into its constituent enzymes by DEAE-Sephadex chromatography. When in the AB complex, proteinase B molecules still bind the specific proteinase B inhibitor from yeast.
mesh_terms: D046911:Macromolecular Substances; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000302:isolation & purification / Q000378:metabolism; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D014367:Tryptophan Synthase / Q000037:antagonists & inhibitors
chemical_list: D046911:Macromolecular Substances; D010447:Peptide Hydrolases; D014367:Tryptophan Synthase