S1 Nuclease.
S1 Nuclease (EC degrades ss DNA and RNA endonucleolytically to yield 5´-phosphoryl terminated products. Ds nucleic acids (DNA, RNA and DNA:RNA hybrids) are resistant to degradation with exception of highly concentrated enzyme. The digestion rate for ssDNA is 75.000 times faster than that of dsDNA. The enzyme will also cleave ss loops within RNA:DNA hybrids.
Unit definition

1 unit produces 1 µg of acid-soluble material per min at 37°C using 0.5 mg/ml heat denatured calf thymus DNA as substrate.

Reaction conditions
For 100 µl reaction use 10 U S1 nuclease, 2 µg DNA, 50 mM NaAc pH 4.6, 1 mM ZnAc, 250 mM NaCl, 50 mg/ml BSA. Incubate at 37°C for 30 min. Stop reaction by addition of 1 µl of 0.5 M EDTA. The reaction conditions will vary with different applications of S1 nuclease.
Store at -20°C.
mapping the 5´ and 3´ ends of RNA transcripts; digesting the hairpin loops formed during the synthesis of cDNA by reverse transcriptase; blunt end formation in ds DNA.

Quality control

activity, no detectable ds nuclease activity.


1. Vogt, V.M. (1973) Eur. J. Biochem. 33, 192. 2. Roberts, T.M. et al. (1979) Proc. Natl. Acad. Sci. USA 76, 760-764. 3. Berk, A.J., Sharp, P.A. (1978) Proc. Natl. Acad. Sci. USA 75, 19274-1278.

Catalog #





Pack size

10.000 U






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