TY - JOUR
T1 - Effect of superoxide dismutase gene inactivation on virulence of Pseudomonas aeruginosa PAO1 toward the silkworm, Bombyx mori
AU - Iiyama, Kazuhiro
AU - Chieda, Yuuka
AU - Lee, Jae Man
AU - Kusakabe, Takahiro
AU - Yasunaga-Aoki, Chisa
AU - Shimizu, Susumu
PY - 2007/3
Y1 - 2007/3
N2 - To investigate the role of superoxide dismutase (SOD) in virulence against the silkworm, Bombyx mori, mutants of Pseudomonas aeruginosa PAO1 lacking manganese-SOD (PO1sodM), iron-SOD (PO1sodB), or both (PAO1sodMB) were generated. The mutants were injected into the hemocoel of B. mori. The virulence decreased in the order PAO1 = PAO1sodM > PAO1sodB > PAO1sodMB. In particular, PAO1sodMB was avirulent at a dose of 105 cells or less. The sod double mutant PAO1sodMB was then complemented with either pSodM or pSodB in trans. In both the complemented strains, the virulence was partially restored. Of the two plasmids, pSodB contributed more to the virulence of P. aeruginosa against B. mori. The results of growth in B. mori hemolymph broth and microscopic analysis suggested that a longer lag phase and superoxide sensitivity correlated with decreased virulence in sod mutants. In conclusion, the SODs are required for full virulence of P. aeruginosa against B. mori and Fe-SOD is more important than Mn-SOD in the infection process.
AB - To investigate the role of superoxide dismutase (SOD) in virulence against the silkworm, Bombyx mori, mutants of Pseudomonas aeruginosa PAO1 lacking manganese-SOD (PO1sodM), iron-SOD (PO1sodB), or both (PAO1sodMB) were generated. The mutants were injected into the hemocoel of B. mori. The virulence decreased in the order PAO1 = PAO1sodM > PAO1sodB > PAO1sodMB. In particular, PAO1sodMB was avirulent at a dose of 105 cells or less. The sod double mutant PAO1sodMB was then complemented with either pSodM or pSodB in trans. In both the complemented strains, the virulence was partially restored. Of the two plasmids, pSodB contributed more to the virulence of P. aeruginosa against B. mori. The results of growth in B. mori hemolymph broth and microscopic analysis suggested that a longer lag phase and superoxide sensitivity correlated with decreased virulence in sod mutants. In conclusion, the SODs are required for full virulence of P. aeruginosa against B. mori and Fe-SOD is more important than Mn-SOD in the infection process.
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U2 - 10.1128/AEM.00981-06
DO - 10.1128/AEM.00981-06
M3 - Article
C2 - 17220257
AN - SCOPUS:33947219775
SN - 0099-2240
VL - 73
SP - 1569
EP - 1575
JO - Applied and environmental microbiology
JF - Applied and environmental microbiology
IS - 5
ER -