The Legionella pneumophila Dps homolog is regulated by iron and involved in multiple stress tolerance.
Iron homeostasis is essential to almost all organisms. In this study, we identified the putative homolog of the iron-storage protein-encoding gene, dpsL, in the intracellular pathogen Legionella pneumophila and demonstrated its expression under iron-limited conditions and its responses to multiple stresses. Quantitative real-time PCR analysis indicated that the expression of dpsL was enhanced under iron limitation regardless of the growth phase. Compared with the wild-type cells, the cells devoid of dpsL were heat and H(2)O(2)-sensitive. In contrast to the dps mutants of other bacteria, the growth of the dpsL mutant in an iron-deprived medium was delayed but finally reached the same cell density as wild-type cells during the stationary phase of growth. The finding that the dpsL mutant is salt resistant suggested the involvement of DpsL in virulence.
Yu
Ming-Jia
MJ
Department of Biochemistry, Sun Yat-sen University Guangzhou, China.
Ren
Jun
J
Zeng
Yong-Lun
YL
Zhou
Shi-Ning
SN
Lu
Yong-Jun
YJ
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D005293:Ferritins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007501:Iron / Q000378:metabolism*; D016952:Legionella pneumophila / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity; D008969:Molecular Sequence Data; D009154:Mutation; D018384:Oxidative Stress; D016415:Sequence Alignment; D014774:Virulence
D001426:Bacterial Proteins; D005293:Ferritins; D006861:Hydrogen Peroxide; D007501:Iron