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Genetic Map of Bacteriophage phiX174
R M Benbow1, C A Hutchison, J D Fabricant
1Division of Biology, California Institute of Technology, Pasadena, California 91109.
Journal of Virology
|May 1, 1971
Summary
Genetic mapping of bacteriophage phiX174 mutations revealed a circular genome. The study determined the precise order of eight cistrons, providing a detailed genetic map for this important virus.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Bacteriophage phiX174 is a well-studied virus with a small genome.
- Understanding its genetic organization is crucial for deciphering viral replication and evolution.
- Previous studies have identified various mutations affecting viral functions.
Purpose of the Study:
- To map temperature-sensitive and nonsense mutations in bacteriophage phiX174.
- To determine the order and relative positions of eight cistrons within the viral genome.
- To elucidate the physical nature of the bacteriophage phiX174 genome.
Main Methods:
- Utilized two-, three-, and four-factor genetic crosses for mutation mapping.
- Analyzed recombinant progeny phage to determine genetic distances.
- Interference analysis was performed to infer genome structure.
Main Results:
- Established a circular genetic map for bacteriophage phiX174.
- Determined the specific order of eight cistrons: D-E-F-G-H-A-B-C.
- Observed high negative interference, supporting a small, closed circular deoxyribonucleic acid genome.
Conclusions:
- The genetic map provides a detailed framework for studying bacteriophage phiX174 gene function.
- The findings confirm the circular nature of the bacteriophage phiX174 genome.
- The observed interference patterns are consistent with a small, covalently closed circular DNA molecule as the viral genome.
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