Nuclease Grade Source Cleavage Specificity MW
(kD) 		pH
Optimum 		Required
Cofactors 		Comments
RNase A Affinity pure
RPA
RNA
Bovine 3' of ss C's and U's 13.77.0-7.5NoneInactivated by 0.1% SDS (1)
RNase I MB*
E. coli
(recombinant) 		3' of ss NTPs of RNA 27.2  NoneResponsible for 98% of the EDTA-resistant RNase activity in E. coliextracts (2)
RNase T1 MB*
RNA
A. oryzae
(recombinant) 		3' of ss G's 11.17.5NoneSpecificity for G is 106X greater than A (3)
RNase V1 RNA
Cobra venom dsRNA 15.97.5Na+
(100 mM)
Mg2+
(0.3 mM)		Cleaves ssRNA at 10% the rate of dsRNA (1)
RNase H MB*
E. coli
(recombinant)		RNA of RNA:DNA hybrids to give 5'-P oligonucleotides17.67.5-9.1Mg2+
(2–4 mM) 		EDTA abolishes activity, but enzyme can still bind RNA:DNA hybrids; Not inhibited by vanadate (3)
DNase I RNase-free
(see also
DNA-free™)
Bovine dsDNA to yield 5'-P dinucleotides and 5'-P oligonucleotides 29.1 7.0-8.0Mg2+
(2–5 mM)
Ca2+
(0.1–1 mM) 		Cleaves ssDNA 500X more slowly than dsDNA (3,4)
*MB = Molecular Biology Grade

References

  1. White, J.S. & White, D.C. (1997) Source Book of Enzymes, CRC Press, Boca Raton, FL.
  2. Zaniewski, R. et al. (1984) J Biol Chem 259: 11651-11653.
  3. Eun, H-M. (1996) Enzymology Primer for Recombinant DNA Technology, Academic Press, Inc., San Diego, CA.
  4. G. Latham, unpublished data.