Streptavidin-Cy5

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 (K_d~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.

Streptavidin-Cy5 is supplied in 0.01M phosphate buffered saline (PBS) pH 7.4, containing 1.0% BSA and 0.09% sodium azide as a preservative.

0.5 - 2.0 µg/ml

The lyophilized streptavidin is stable when stored at 2-8°C. After reconstitution the streptavidin may be stored as an undiluted liquid at 2-8°C for six weeks. For extended storage as a liquid an equal volume of ACS grade or better glycerol should be added to the vial (bringing the final concentration of streptavidin to 50%) and stored at –20°C in a manual defrost freezer. Avoid Repeated Freeze Thaw Cycles. The reconstituted material may also be aliquoted and frozed at -70°C without the addition of glycerol.

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