Abstract
Recombinants obtained from matings of Nocardia erythropolis × N. canicruria were tested for their genetic stability by comparing phenotypes from direct selection with the same population after unselected growth. Contraselective loci were employed in various combinations in order that all of the mapped characters might be subjected to unselected analysis. Some recombinant class types appeared as stable haploids, whereas others behaved as heterozygous diploids, segregating out new phenotypes. All regions of the parental genomes were found to be involved in segregation, implying that the entire mapped region can become merozygotic under standard mating conditions. On the basis of segregating phenotypes, the genetic potentials of these compatible nocardiae were ascertained as follows: the formation of a diploid with subsequent segregation of parental or haploid recombinant genomes or both; persistence of the diploid through many generations; continuing reassortment of genetic information by multiple matings between parental or recombinant organisms; and, very probably, second-round recombinations within the diploid. A considerable difference in the nuclear division time between the parental organisms was postulated to have significant effects on the nature of the unselected segregants.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- ADAMS J. N., McCLUNG N. M. Comparison of the developmental cycles of some members of the genus Nocardia. J Bacteriol. 1962 Aug;84:206–216. doi: 10.1128/jb.84.2.206-216.1962. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ADAMS J. N. RECOMBINATION BETWEEN NOCARDIA ERYTHROPOLIS AND NOCARDIA CANICRURIA. J Bacteriol. 1964 Oct;88:865–876. doi: 10.1128/jb.88.4.865-876.1964. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Adams J. N. Partial exclusion of the Nocardia erythropolis chromosome in nocardial recombinants. J Bacteriol. 1968 Nov;96(5):1750–1759. doi: 10.1128/jb.96.5.1750-1759.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Adams J. N. Studies on the fragmentation of Nocardia erythropolis in liquid medium. Can J Microbiol. 1966 Jun;12(3):433–441. doi: 10.1139/m66-064. [DOI] [PubMed] [Google Scholar]
- Brownell G. H., Adams J. N., Bradley S. G. Growth and characterization of nocardiophages for Nocardia canicruria and Nocardia erythropolis mating types. J Gen Microbiol. 1967 May;47(2):247–256. doi: 10.1099/00221287-47-2-247. [DOI] [PubMed] [Google Scholar]
- Brownell G. H., Adams J. N. Linkage and segregation of a mating type specific phage and resistance characters in nocardial recombinants. Genetics. 1968 Nov;60(3):437–448. doi: 10.1093/genetics/60.3.437. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brownell G. H., Adams J. N. Linkage and segregation of unselected markers in matings of Nocardia erythropolis with Nocardia canicruria. J Bacteriol. 1967 Sep;94(3):650–659. doi: 10.1128/jb.94.3.650-659.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brownell G. H., Kelly K. L. Inheritance of mating factors in nocardial recombinants. J Bacteriol. 1969 Jul;99(1):25–36. doi: 10.1128/jb.99.1.25-36.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Demerec M., Adelberg E. A., Clark A. J., Hartman P. E. A proposal for a uniform nomenclature in bacterial genetics. Genetics. 1966 Jul;54(1):61–76. doi: 10.1093/genetics/54.1.61. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hopwood D. A. Genetic analysis and genome structure in Streptomyces coelicolor. Bacteriol Rev. 1967 Dec;31(4):373–403. doi: 10.1128/br.31.4.373-403.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]