Abstract | PURPOSE: The role of protease IV in the pathogenesis of Pseudomonas aeruginosa keratitis was investigated by comparing a mutant strain completely deficient in protease IV activity with its protease IV activity-producing parent. METHODS: RESULTS: The protease IV-deficient strain PA103-29::Tn9 had significantly reduced corneal virulence relative to its parent strain PA103-29 in both a rabbit intrastromal model and a mouse topical model of infection. In the rabbit model, ocular damage ( slit lamp examination score) mediated by the parent strain was severe at 32 hours after infection, whereas damage mediated by the mutant was minimal at both 32 and 55 hours after infection. This difference in virulence was not a result of differences in growth in vivo, because both strains grew equally. In the mouse model, eyes inoculated with the protease IV-producing parent strain had significant corneal damage as early as 24 hours after infection, whereas the protease IV-deficient mutant strain produced no significant corneal damage during 6 days of infection. CONCLUSIONS: The ability to produce active protease IV was the determining factor in the severity of corneal virulence. Protease IV appears to mediate corneal virulence and should be considered as a target in the development of medications designed to minimize corneal damage during Pseudomonas keratitis.
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Authors | L S Engel, J A Hobden, J M Moreau, M C Callegan, J M Hill, R J O'Callaghan |
Journal | Investigative ophthalmology & visual science
(Invest Ophthalmol Vis Sci)
Vol. 38
Issue 8
Pg. 1535-42
(Jul 1997)
ISSN: 0146-0404 [Print] United States |
PMID | 9224281
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Peptide Hydrolases
- protease IV
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Topics |
- Animals
- Colony Count, Microbial
- Cornea
(microbiology)
- Corneal Diseases
(pathology)
- Corneal Stroma
(microbiology)
- Female
- Mice
- Peptide Hydrolases
(deficiency)
- Pseudomonas Infections
(pathology)
- Pseudomonas aeruginosa
(enzymology, genetics, pathogenicity)
- Rabbits
- Species Specificity
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