Abstract
Legionella pneumophila, an intracellular parasite of macrophages and protozoa, requires iron for extra- and intracellular growth. In a new screen of a mutant library of L. pneumophila for strains defective for growth on agar media lacking supplemental iron, seven mutants were obtained. All of the mutants had a disruption in the cytochrome c maturation (ccm) locus; two had insertions in ccmB, two in ccmC, and three in ccmF. The ccm mutants were unable to multiply within macrophage-like cells (i.e., U937 and THP-1 cells) and Hartmannella vermiformis amoebae. A competition assay in A/J mice revealed that ccm mutants are severely defective for growth within the lung. Taken together, these data confirm that ccm and cytochrome c maturation proteins are required for L. pneumophila growth in low iron, intracellular infection, and virulence.
Original language | English (US) |
---|---|
Pages (from-to) | 249-256 |
Number of pages | 8 |
Journal | FEMS Microbiology Letters |
Volume | 241 |
Issue number | 2 |
DOIs | |
State | Published - Dec 15 2004 |
Funding
We thank Shawn Starkenburg and Ombeline Rossier for technical assistance. Jennifer Naylor was supported in part by a Philip Morris Postdoctoral Fellowship. This work was funded by NIH Grant AI34937 awarded to N.P.C.
Keywords
- Cytochrome c maturation
- Hartmannella vermiformis
- Iron acquisition
- Legionella pneumophila
- Legionnaires' disease
- Macrophage
ASJC Scopus subject areas
- Genetics
- Molecular Biology
- Microbiology