Streptavidin is a biotin binding protein present in the fermentation broth of the bacterium Streptomyces avidinii. Each molecule of streptavidin can bind four molecules of biotin with a high affinity constant (Kd~10
-15). Unlike native avidin, streptavidin is not glycosylated and has a near neutral isoelectric point (pI ~ 5-6) vs a pI of 10 for native avidin.
R-phycoerythrin (R-PE) has a molecular weight of 240 kDa and is purified from red algae. R-PE is an intensely bright phycobiliprotein with an absorption maxima at approximately 496, 546 and 565 nm, and a fluorescence emission maximum of ~578 nm.
Streptavidin-R-PE is supplied in 0.01M phosphate buffered saline (PBS) pH 7.6, containing 15 mg/ml BSA and 0.05% sodium azide as a preservative.
Storage and Stability
This R-PE conjugate is stable when stored at 2-8°C. Do not freeze.
pI = 5 - 6
Applications and Suggested Working Dilutions
Streptavidin-R-PE has been tested by flow cytometric analysis to detect biotinylated primary antibodies. A working dilution of 1:50-1:200 is suitable for most applications.
Country of Origin
Products are for research use only. Not for use in diagnostic or therapeutic procedures.
359 Consort Drive | St. Louis, MO 63011 | (800) 538-1145 | (636) 527-5545 fax