Viability of lambda phages carrying a perfect palindrome in the absence of recombination nucleases - PubMed (original) (raw)

PMID: 6312322
DOI: 10.1038/305448a0

Viability of lambda phages carrying a perfect palindrome in the absence of recombination nucleases

D R Leach et al. Nature. 1983.

Abstract

In Escherichia coli in vitro constructions of perfect palindromes larger than 30 base pairs (bp) long have in general been unstable. A perfect palindrome has the unique possibility of forming a cruciform structure, and it is this feature which probably results in its instability. Negative supercoiling favours the formation of the cruciform conformation, which in turn causes the molecule to relax. This relaxation may render replicons containing large perfect palindromes inviable. An alternative hypothesis for inviability has been that the cruciform interferes with replication by favouring strand switching by polymerase I. Here we show that the simultaneous absence of two recombination nucleases, the recBC product, exonuclease V, and the sbcB product, exonuclease I, confers viability on a derivative of phage lambda carrying a perfect palindrome of inverted repeat length 1,600 bases. This observation suggests a third hypothesis--that nucleolytic cleavage of the cruciform is responsible for the inviability of the phage. Such an activity has been shown in vitro for T4 exonuclease VII.

PubMed Disclaimer

Cited by

Context effects in the formation of deletions in Escherichia coli.
Kazic T, Berg DE. Kazic T, et al. Genetics. 1990 Sep;126(1):17-24. doi: 10.1093/genetics/126.1.17. Genetics. 1990. PMID: 2227379 Free PMC article.
Statistical analyses of counts and distributions of restriction sites in DNA sequences.
Karlin S, Burge C, Campbell AM. Karlin S, et al. Nucleic Acids Res. 1992 Mar 25;20(6):1363-70. doi: 10.1093/nar/20.6.1363. Nucleic Acids Res. 1992. PMID: 1313968 Free PMC article.
Identification of a retrovirus-like repetitive element in human DNA.
Mager DL, Henthorn PS. Mager DL, et al. Proc Natl Acad Sci U S A. 1984 Dec;81(23):7510-4. doi: 10.1073/pnas.81.23.7510. Proc Natl Acad Sci U S A. 1984. PMID: 6095301 Free PMC article.
Propagation of some human DNA sequences in bacteriophage lambda vectors requires mutant Escherichia coli hosts.
Wyman AR, Wolfe LB, Botstein D. Wyman AR, et al. Proc Natl Acad Sci U S A. 1985 May;82(9):2880-4. doi: 10.1073/pnas.82.9.2880. Proc Natl Acad Sci U S A. 1985. PMID: 3157994 Free PMC article.
The nature of extra-chromosomal maintenance of transforming plasmids in the filamentous basidiomycete Phanerochaete chrysosporium.
Randall TA, Reddy CA. Randall TA, et al. Curr Genet. 1992 Mar;21(3):255-60. doi: 10.1007/BF00336850. Curr Genet. 1992. PMID: 1314140

Viability of lambda phages carrying a perfect palindrome in the absence of recombination nucleases - PubMed (original) (raw)