Abstract
Recombination frequencies have been determined in crosses involving 28 mutant strains for 20 of which the site of the alteration is known from studies of amino-acid substitutions in the protein products. Three of these mutants showed especially high frequencies of recombination when crossed to other single mutants or when crossed to a strain carrying two alterations at opposite ends of the trpA gene. There is no obvious molecular explanation of the high recombination of these three mutants. They include one missense mutant, one amber and one ochre. The low-frequency recombination mutants include all these same classes as well as frameshift mutants. There is nothing unique about the intragenic location of the high-recombination mutants; in each case there is at least one low-recombination mutant in the same codon.—Crosses involving mutants which were isolated in an altered wild type have shown that the behavior of a high-recombination mutant does not result from its molecular configuration alone, but from its combination with the homologous wild-type sequence from the other parent.—Several lines of evidence indicate that recombination in this system frequently involves closely-spaced double exchanges (about 40 codons apart).
Full Text
The Full Text of this article is available as a PDF (1.0 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Barbour S. D., Nagaishi H., Templin A., Clark A. J. Biochemical and genetic studies of recombination proficiency in Escherichia coli. II. Rec+ revertants caused by indirect suppression of rec- mutations. Proc Natl Acad Sci U S A. 1970 Sep;67(1):128–135. doi: 10.1073/pnas.67.1.128. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Broker T. R., Lehman I. R. Branched DNA molecules: intermediates in T4 recombination. J Mol Biol. 1971 Aug 28;60(1):131–149. doi: 10.1016/0022-2836(71)90453-0. [DOI] [PubMed] [Google Scholar]
- Chase M, Doermann A H. High Negative Interference over Short Segments of the Genetic Structure of Bacteriophage T4. Genetics. 1958 May;43(3):332–353. doi: 10.1093/genetics/43.3.332. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Crawford I. P., Preiss J. Distribution of closely linked markers following intragenic recombination in Escherichia coli. J Mol Biol. 1972 Nov 28;71(3):717–733. doi: 10.1016/s0022-2836(72)80034-2. [DOI] [PubMed] [Google Scholar]
- DEMEREC M., DEMEREC Z. E. Analysis of linkage relationships in Salmonella by transduction techniques. Brookhaven Symp Biol. 1956 Feb;(8):75–87. [PubMed] [Google Scholar]
- Doermann A. H., Parma D. H. Recombination in bacteriophage T4. J Cell Physiol. 1967 Oct;70(2 Suppl):147–164. doi: 10.1002/jcp.1040700411. [DOI] [PubMed] [Google Scholar]
- Drapeau G. R., Brammar W. J., Yanofsky C. Amino acid replacements of the glutamic acid residue at position 48 in the tryptophan synthetase A protein of Escherichia coli. J Mol Biol. 1968 Jul 28;35(2):357–367. doi: 10.1016/s0022-2836(68)80030-0. [DOI] [PubMed] [Google Scholar]
- Gajewski H. Aufnahmetechnik bei der Mammographie. Rontgenpraxis. 1967 Aug;20(8):177–188. [PubMed] [Google Scholar]
- Ikeda H., Tomizawa J. I. Transducing fragments in generalized transduction by phage P1. I. Molecular origin of the fragments. J Mol Biol. 1965 Nov;14(1):85–109. doi: 10.1016/s0022-2836(65)80232-7. [DOI] [PubMed] [Google Scholar]
- Tomizawa J. I. Molecular mechanisms of genetic recombination in bacteriophage: joint molecules and their conversion to recombinant molecules. J Cell Physiol. 1967 Oct;70(2 Suppl):201–213. doi: 10.1002/jcp.1040700414. [DOI] [PubMed] [Google Scholar]
- YANOFSKY C., CARLTON B. C., GUEST J. R., HELINSKI D. R., HENNING U. ON THE COLINEARITY OF GENE STRUCTURE AND PROTEIN STRUCTURE. Proc Natl Acad Sci U S A. 1964 Feb;51:266–272. doi: 10.1073/pnas.51.2.266. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yanofsky C., Horn V., Bonner M., Stasiowski S. Polarity and enzyme functions in mutants of the first three genes of the tryptophan operon of Escherichia coli. Genetics. 1971 Dec;69(4):409–433. doi: 10.1093/genetics/69.4.409. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yanofsky C., Ito J. Nonsense codons and polarity in the tryptophan operon. J Mol Biol. 1966 Nov 14;21(2):313–334. doi: 10.1016/0022-2836(66)90102-1. [DOI] [PubMed] [Google Scholar]