DescriptionDuplex DNA is isolated from bacteriophage lambda (cI857ind 1 Sam 7). The bacteriophage is grown in an E. coli host which is deficient in adenine methylase (dam-). Therefore, those deoxyadenosine positions which are methylated in a wild type E. coli host are not methylated in the dam- host. This DNA gives complete digests with restriction endonucleases that are sensitive to dam methylation. Lambda DNA (N6-methyladenine-free) is 48,502 base pairs in length.
SourceThe phage is isolated from a heat-inducible E. coli (dam-) lambda lysogen. The DNA is isolated from purified phage by phenol extraction and dialyzed against 10 mM Tris-HCl (pH 8.0) and 1 mM EDTA.
Properties and Usage
10 mM Tris-HCl
1 mM EDTA
pH 8.0 @ 25°C
- The advantage of this DNA is that it gives complete digests with those restriction endonucleases (BclI, MboI, DpnII, etc.) whose recognition sites are partially modified by most E. coli strains.
- Daniels, D.L. et al. (1983). Appendix II: Complete Annotated Lambda Sequence. R.W. Hendrix, J.W. Roberts, F.W. Stahl and R.A. Weisberg(Ed.), Lambda-II. 519-676. New York: Cold Spring Harbor Laboratory Press.