title: Postsecretory modifications of streptavidin.
abstract: Streptavidin, an extracellular biotin-binding protein from Streptomyces avidinii, exhibits a multiplicity in its electrophoretic mobility pattern which depends both upon the conditions for growth of the bacterium and upon the protocol used in the purification of the protein. The observed structural heterogeneity appears to reflect the action of two types of postsecretory molecular events: proteolytic digestion of the intact Mr-18,000 subunit to a minimal molecular size (approx. Mr 14,000), and aggregation of the native tetramer into higher-order oligomeric forms. The extent of subunit degradation and/or tetrameric aggregation affects the capacity of a given streptavidin preparation to interact with biotin-conjugated proteins in different assay systems.
authors.affiliation: Department of Biophysics, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: E A
authors.initials: EA
authors.lastname: Bayer
authors.forename: H
authors.initials: H
authors.lastname: Ben-Hur
authors.forename: Y
authors.initials: Y
authors.lastname: Hiller
authors.forename: M
authors.initials: M
authors.lastname: Wilchek
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000302:isolation & purification* / Q000378:metabolism; D001710:Biotin / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011487:Protein Conformation; D019809:Streptavidin
chemical_list: D001426:Bacterial Proteins; D001710:Biotin; D019809:Streptavidin