Product Name: Recombinant Core Streptavidin (rc-SA)
Catalog Number: NRPA09S
Packaging Details: 1mg, 10mg, 100mg, 500mg
Formulation: lyophilized from 5 mM PB (4 mM Na2HPO4, 1 mM NaH2PO4, pH 7.4)
Mol. Weight: 13.5 kDa subunit; Tetramer 54kDa
Pi theory: 6.04
Theoretical activity: 18.1 U / mg protein (rc-SA: Biotin = 1: 4 (mol: mol))
Resources: Escherichia coli (E. coli)
Purity: ≥95% by SDS-PAGE analysis
Test activity: ≥15 U / mg protein (determined by NUPTEC according to the modified green method)
Storage condition: -20 oC
Storage duration: 3 years
Streptavidin is a homotetrameric protein found in the culture broth of Streptomyces avidinii. Similar to avidin, one mole of streptavidin can bind 4 moles of biotin with a high affinity virtually unmatched in nature. Streptavidin lacks the carbohydrate side chains present in avidin and has an isoelectric point close to neutrality. Therefore, it has a lowering non-specific binding level compared to avidin. Streptavidin has been widely applied in various biological fields, such as ELISA, IHC, TRFIA, PCR quantification, isolation of single-stranded nucleotides, purification of biomolecules, and production of monoclonal antibodies.
Compared to native streptavidin, RC-SA improves in stability and solubility by eliminating sequences unrelated to activity. In addition, a cysteine residue is inserted at the C-terminus of RC-SA for covalent conjugation to the resin.