• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.49-55
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• 2000

Lysogenic conversion of Staphylococcus aureus to loss of ${\beta}-hemolysin$ production by serological group F phages is always associated with gain in staphylokinase production. In this study, the new phages belonging to serotype F were detected during the course of isolation of phages from Staph aureus of bovine origin and some characteristics of the new phages isolated were investigated. The new phages, ${\phi}470$ and ${\phi}499$, isolated from Staph aureus producing ${\beta}-hemolysin$ and staphylokinase(${\beta}^+\;K^+$) were found to convert ${\beta}^+\;K^+$ strain to ${\beta}^+K\;^+$, Staph aureus strains lysogenized by this serotype F single-converting phage ${\phi}470$ or ${\phi}499$ could be again lysogenized with serotype F double-converting phage ${\phi}506$. The frequency of lysogenization of indicator strains by serotype F single-converting phage was 100%, whereas the frequency for serotype F double-converting phage ${\phi}506$ varied from 4.2% to 97.6% according to the indicator strains. The indicator strain lysogenized with phage ${\phi}470$ was resistant to phage ${\phi}499$, and vice versa, but not to phage ${\phi}506$. Therefore, phage ${\phi}470$ and ${\phi}499$ were shown to be identical by immunity test.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.246-251
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• 1994

Pseudomonas syringae pv. tabaci(Pa45) Tox$^{-}$ cells were infected with phage Ps90 strain isolated form the natural source, and the Ps90 lysogenized bacterial cells were then obtained. The lyxohenized cells produced tabtoxin and the phage induction occured when the cells treated with mitomycin C. The Southren hybridization alnalysis of the four EcoRI-treated plasmid fragments and the EcoRI-digested genomic DNA of Tox$^{+}$ and Tox$^{-}$ strains using phage DNA as a probe showed that only those DNA fragment of Tox$^{+}$ strain were related to the Ps90 phage DNA. Based on these results, the tabtoxin producing DNA fragments of the bacteris are presumed to have originated from the same phage DNA, and to be responsible for the pathogenecity of the bactrial strains.