1 Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01002
ABSTRACT
We predicted that, among mutants resistant to infection by single-stranded deoxyribonucleic acid viruses, there would be some also resistant to "infection" by single-stranded conjugal deoxyribonucleic acid. Approximately 5% of the Escherichia coli K-12 females selected for resistance to phage ST-1 were defective as recipients in conjugation. These spontaneous mutants fell into two classes. Type A accepted both plasmid and chromosomal markers at greatly reduced frequencies (<106 of normal for at least one strain), formed "rough" colonies, and (unlike their parent) were nonflagellated. Type B strains accepted both chromosomal and plasmid markers at reduced frequencies (102 to 101 of normal), were temperature sensitive for growth, and showed increased susceptibility towards antibiotics and deoxycholate. Both classes of mutants also were resistant to certain female-specific viruses.
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
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