The ral gene of phage lambda. I. Identification of a non-essential gene that modulates restriction and modification in E. coli
- PMID: 6256607
- DOI: 10.1007/BF00268447
The ral gene of phage lambda. I. Identification of a non-essential gene that modulates restriction and modification in E. coli
Abstract
Host controlled restriction in Escherichia coli can be relieved by pre-infecting restricting cells with modified lambda helper phages. This process, in which intact unmodified phage genomes are allowed to escape restriction attack, is mediated by a newly identified lambda function called ral. The ral gene has been located by deletion mapping between cIII and N. Efficient expression of the ral gene requires the product of the regulator gene N. Polyacrylamide gel analysis of the lambda proteins specified by the cIII-N region failed to reveal the product of the ral gene, but demonstrated that protein Ea10 is encoded by a gene located immediately to the left of ral. From these results the map order cIII-Ea10-ral-TL1-N was deduced. Ral specifically alleviates restriction in E. coli K and E. coli B, but does not affect restriction systems EcoRI, EcoRII and EcoP1. In addition, ral enhances the modification activity of the EcoK and EcoB restriction enzymes: we observed that efficient modification of progeny phages obtained by propagating unmodified lambda phages in r-m+ hosts, is dependent upon the presence of ral. We thus conclude that the ral gene product acts by modulating the restriction and modification activities of the type I restriction systems in E. coli, and the possible mechanisms will be discussed.
Similar articles
-
Restriction alleviation by bacteriophages lambda and lambda reverse.J Virol. 1981 May;38(2):621-31. doi: 10.1128/JVI.38.2.621-631.1981. J Virol. 1981. PMID: 6264133 Free PMC article.
-
The ral gene of phage lambda. II. Isolation and characterization of ral deficient mutants.Mol Gen Genet. 1980;179(1):75-80. doi: 10.1007/BF00268448. Mol Gen Genet. 1980. PMID: 6256608
-
Modification enhancement by the restriction alleviation protein (Ral) of bacteriophage lambda.J Mol Biol. 1986 Jul 5;190(1):11-22. doi: 10.1016/0022-2836(86)90071-9. J Mol Biol. 1986. PMID: 3023633
-
A comprehensive molecular map of bacteriophage lambda.Gene. 1979 Nov;7(3-4):217-70. doi: 10.1016/0378-1119(79)90047-7. Gene. 1979. PMID: 160360 Review.
-
[Transducing lambda phages with Escherichia coli genes].Genetika. 1981;17(8):1351-89. Genetika. 1981. PMID: 6456172 Review. Russian.
Cited by
-
Systematic and scalable genome-wide essentiality mapping to identify nonessential genes in phages.PLoS Biol. 2023 Dec 4;21(12):e3002416. doi: 10.1371/journal.pbio.3002416. eCollection 2023 Dec. PLoS Biol. 2023. PMID: 38048319 Free PMC article.
-
UV-induced allevation of lambda restriction in Escherichia coli K-12: kinetics of induction and specificity of this SOS function.Mol Gen Genet. 1982;186(1):111-7. doi: 10.1007/BF00422921. Mol Gen Genet. 1982. PMID: 6213835
-
Restriction nuclease and enzymatic analysis of transposon-induced mutations of the Rac prophage which affect expression and function of recE in Escherichia coli K-12.J Bacteriol. 1983 Nov;156(2):727-36. doi: 10.1128/jb.156.2.727-736.1983. J Bacteriol. 1983. PMID: 6313616 Free PMC article.
-
Effect of bacteriophage lambda infection on synthesis of groE protein and other Escherichia coli proteins.J Bacteriol. 1982 Mar;149(3):1050-63. doi: 10.1128/jb.149.3.1050-1063.1982. J Bacteriol. 1982. PMID: 6460750 Free PMC article.
-
Nucleotide sequence of the gene (ard) encoding the antirestriction protein of plasmid colIb-P9.J Bacteriol. 1991 Sep;173(18):5887-92. doi: 10.1128/jb.173.18.5887-5892.1991. J Bacteriol. 1991. PMID: 1653225 Free PMC article.
References
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Molecular Biology Databases