Infect. Immun., 12 1997, 5057-5066, Vol 65, No. 12
Copyright © 1997, American Society for Microbiology

Characterization of a new region required for macrophage killing by Legionella pneumophila

G Segal and HA Shuman
Department of Microbiology, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.

In a previous study, a collection of 55 Legionella pneumophila mutants defective for macrophage killing was isolated by transposon mutagenesis. In this study, nine of these mutants that belong to the same DNA hybridization group (group 3) were characterized. A wild-type DNA fragment that covers this DNA hybridization group was cloned and sequenced. This region was found to contain six new genes (designated icmT, icmS, icmR, icmQ, icmP, and icmO), five of which contain at least one transposon insertion. No transposon insertion was found in icmS. However, this gene was found to be required for macrophage killing, since a kanamycin resistance cassette introduced into icmS by gene replacement resulted in a mutant that was attenuated for macrophage killing. A plasmid containing the DNA fragment that covers this region complements all the mutants for macrophage killing, although various levels of complementation were observed for mutants in different genes. Complementation tests were also performed with plasmids containing one or two of these genes, as well as with plasmids containing nonpolar in- frame deletions. The results from these complementation tests indicated that all six genes located in this region are needed for macrophage killing and that they are probably arranged as two transcriptional units (icmTS and icmPO) and two genes (icmR and icmQ). A region upstream of the coding sequence of several icm genes may contain a potential promoter and/or regulatory site. Homology searches show that icmP and icmO bear significant homology to the trbA and trbC genes from the Salmonella R64 plasmid, respectively. The sequences of the other four genes do not show significant homology with any entries in sequence databases.

This article has been cited by other articles:

• Barysheva, O. V., Fujii, J., Takaesu, G., Yoshida, S.-i. (2008). Application of unstable Gfp variants to the kinetic study of Legionella pneumophila icm gene expression during infection. Microbiology 154: 1015-1025 [Abstract] [Full Text]  
• Altman, E., Segal, G. (2008). The Response Regulator CpxR Directly Regulates Expression of Several Legionella pneumophila icm/dot Components as Well as New Translocated Substrates. J. Bacteriol. 190: 1985-1996 [Abstract] [Full Text]  
• Feldman, M., Segal, G. (2007). A Pair of Highly Conserved Two-Component Systems Participates in the Regulation of the Hypervariable FIR Proteins in Different Legionella Species. J. Bacteriol. 189: 3382-3391 [Abstract] [Full Text]  
• Bandyopadhyay, P., Liu, S., Gabbai, C. B., Venitelli, Z., Steinman, H. M. (2007). Environmental Mimics and the Lvh Type IVA Secretion System Contribute to Virulence-Related Phenotypes of Legionella pneumophila. Infect. Immun. 75: 723-735 [Abstract] [Full Text]  
• LeBlanc, J. J., Davidson, R. J., Hoffman, P. S. (2006). Compensatory Functions of Two Alkyl Hydroperoxide Reductases in the Oxidative Defense System of Legionella pneumophila.. J. Bacteriol. 188: 6235-6244 [Abstract] [Full Text]  
• Broich, M., Rydzewski, K., McNealy, T. L., Marre, R., Flieger, A. (2006). The Global Regulatory Proteins LetA and RpoS Control Phospholipase A, Lysophospholipase A, Acyltransferase, and Other Hydrolytic Activities of Legionella pneumophila JR32. J. Bacteriol. 188: 1218-1226 [Abstract] [Full Text]  
• WALKER, D. H., YU, X.-J. (2005). Progress in Rickettsial Genome Analysis from Pioneering of Rickettsia prowazekii to the Recent Rickettsia typhi. Ann. N. Y. Acad. Sci. 1063: 13-25 [Abstract] [Full Text]  
• Yerushalmi, G., Zusman, T., Segal, G. (2005). Additive Effect on Intracellular Growth by Legionella pneumophila Icm/Dot Proteins Containing a Lipobox Motif. Infect. Immun. 73: 7578-7587 [Abstract] [Full Text]  
• Miyake, M., Watanabe, T., Koike, H., Molmeret, M., Imai, Y., Abu Kwaik, Y. (2005). Characterization of Legionella pneumophila pmiA, a Gene Essential for Infectivity of Protozoa and Macrophages. Infect. Immun. 73: 6272-6282 [Abstract] [Full Text]  
• Abu-Zant, A., Santic, M., Molmeret, M., Jones, S., Helbig, J., Abu Kwaik, Y. (2005). Incomplete Activation of Macrophage Apoptosis during Intracellular Replication of Legionella pneumophila. Infect. Immun. 73: 5339-5349 [Abstract] [Full Text]  
• Feldman, M., Zusman, T., Hagag, S., Segal, G. (2005). Coevolution between nonhomologous but functionally similar proteins and their conserved partners in the Legionella pathogenesis system. Proc. Natl. Acad. Sci. USA 102: 12206-12211 [Abstract] [Full Text]  
• Buscher, B. A., Conover, G. M., Miller, J. L., Vogel, S. A., Meyers, S. N., Isberg, R. R., Vogel, J. P. (2005). The DotL Protein, a Member of the TraG-Coupling Protein Family, Is Essential for Viability of Legionella pneumophila Strain Lp02. J. Bacteriol. 187: 2927-2938 [Abstract] [Full Text]  
• Albers, U., Reus, K., Shuman, H. A., Hilbi, H. (2005). The amoebae plate test implicates a paralogue of lpxB in the interaction of Legionella pneumophila with Acanthamoeba castellanii. Microbiology 151: 167-182 [Abstract] [Full Text]  
• Feldman, M., Segal, G. (2004). A Specific Genomic Location within the icm/dot Pathogenesis Region of Different Legionella Species Encodes Functionally Similar but Nonhomologous Virulence Proteins. Infect. Immun. 72: 4503-4511 [Abstract] [Full Text]  
• Bandyopadhyay, P., Xiao, H., Coleman, H. A., Price-Whelan, A., Steinman, H. M. (2004). Icm/Dot-Independent Entry of Legionella pneumophila into Amoeba and Macrophage Hosts. Infect. Immun. 72: 4541-4551 [Abstract] [Full Text]  
• Zusman, T., Feldman, M., Halperin, E., Segal, G. (2004). Characterization of the icmH and icmF Genes Required for Legionella pneumophila Intracellular Growth, Genes That Are Present in Many Bacteria Associated with Eukaryotic Cells. Infect. Immun. 72: 3398-3409 [Abstract] [Full Text]  
• Dumenil, G., Montminy, T. P., Tang, M., Isberg, R. R. (2004). IcmR-regulated Membrane Insertion and Efflux by the Legionella pneumophila IcmQ Protein. J. Biol. Chem. 279: 4686-4695 [Abstract] [Full Text]  
• Miyamoto, H., Yoshida, S.-i., Taniguchi, H., Shuman, H. A. (2003). Virulence Conversion of Legionella pneumophila by Conjugal Transfer of Chromosomal DNA. J. Bacteriol. 185: 6712-6718 [Abstract] [Full Text]  
• Gal-Mor, O., Segal, G. (2003). Identification of CpxR as a Positive Regulator of icm and dot Virulence Genes of Legionella pneumophila. J. Bacteriol. 185: 4908-4919 [Abstract] [Full Text]  
• Zusman, T., Yerushalmi, G., Segal, G. (2003). Functional Similarities between the icm/dot Pathogenesis Systems of Coxiella burnetii and Legionella pneumophila. Infect. Immun. 71: 3714-3723 [Abstract] [Full Text]  
• GE, H., CHUANG, Y.-Y. E., ZHAO, S., TEMENAK, J. J., CHING, W.-M. (2003). Genomic Studies of Rickettsia prowazekii Virulent and Avirulent Strains. Ann. N. Y. Acad. Sci. 990: 671-677 [Full Text]  
• Gal-Mor, O., Zusman, T., Segal, G. (2002). Analysis of DNA Regulatory Elements Required for Expression of the Legionella pneumophilaicm and dot Virulence Genes. J. Bacteriol. 184: 3823-3833 [Abstract] [Full Text]  
• Rankin, S., Li, Z., Isberg, R. R. (2002). Macrophage-Induced Genes of Legionella pneumophila: Protection from Reactive Intermediates and Solute Imbalance during Intracellular Growth. Infect. Immun. 70: 3637-3648 [Abstract] [Full Text]  
• Samrakandi, M. M., Cirillo, S. L. G., Ridenour, D. A., Bermudez, L. E., Cirillo, J. D. (2002). Genetic and Phenotypic Differences between Legionella pneumophila Strains. J. Clin. Microbiol. 40: 1352-1362 [Abstract] [Full Text]  
• Tilney, L. G., Harb, O. S., Connelly, P. S., Robinson, C. G., Roy, C. R. (2002). How the parasitic bacterium Legionella pneumophila modifies its phagosome and transforms it into rough ER: implications for conversion of plasma membrane to the ER membrane. J. Cell Sci. 114: 4637-4650 [Abstract] [Full Text]  
• Molmeret, M., Alli, O. A. T., Zink, S., Flieger, A., Cianciotto, N. P., Kwaik, Y. A. (2002). icmT Is Essential for Pore Formation-Mediated Egress of Legionella pneumophila from Mammalian and Protozoan Cells. Infect. Immun. 70: 69-78 [Abstract] [Full Text]  
• Zusman, T., Gal-Mor, O., Segal, G. (2002). Characterization of a Legionella pneumophila relA Insertion Mutant and Roles of RelA and RpoS in Virulence Gene Expression. J. Bacteriol. 184: 67-75 [Abstract] [Full Text]  
• Khelef, N., Shuman, H. A., Maxfield, F. R. (2001). Phagocytosis of Wild-Type Legionella pneumophila Occurs through a Wortmannin-Insensitive Pathway. Infect. Immun. 69: 5157-5161 [Abstract] [Full Text]  
• Polesky, A. H., Ross, J. T. D., Falkow, S., Tompkins, L. S. (2001). Identification of Legionella pneumophila Genes Important for Infection of Amoebas by Signature-Tagged Mutagenesis. Infect. Immun. 69: 977-987 [Abstract] [Full Text]  
• Sieira, R., Comerci, D. J., Sánchez, D. O., Ugalde, R. A. (2000). A Homologue of an Operon Required for DNA Transfer in Agrobacterium Is Required in Brucella abortus for Virulence and Intracellular Multiplication. J. Bacteriol. 182: 4849-4855 [Abstract] [Full Text]  
• Matthews, M., Roy, C. R. (2000). Identification and Subcellular Localization of the Legionella pneumophila IcmX Protein: a Factor Essential for Establishment of a Replicative Organelle in Eukaryotic Host Cells. Infect. Immun. 68: 3971-3982 [Abstract] [Full Text]  
• Solomon, J. M., Rupper, A., Cardelli, J. A., Isberg, R. R. (2000). Intracellular Growth of Legionella pneumophila in Dictyostelium discoideum, a System for Genetic Analysis of Host-Pathogen Interactions. Infect. Immun. 68: 2939-2947 [Abstract] [Full Text]  
• Diez, E., Yaraghi, Z., MacKenzie, A., Gros, P. (2000). The Neuronal Apoptosis Inhibitory Protein (Naip) Is Expressed in Macrophages and Is Modulated After Phagocytosis and During Intracellular Infection with Legionella pneumophila. J. Immunol. 164: 1470-1477 [Abstract] [Full Text]  
• Hales, L. M., Shuman, H. A. (1999). The Legionella pneumophila rpoS Gene Is Required for Growth within Acanthamoeba castellanii. J. Bacteriol. 181: 4879-4889 [Abstract] [Full Text]  
• Joshi, A. D., Swanson, M. S. (1999). Comparative Analysis of Legionella pneumophila and Legionella micdadei Virulence Traits. Infect. Immun. 67: 4134-4142 [Abstract] [Full Text]  
• Segal, G., Shuman, H. A. (1999). Legionella pneumophila Utilizes the Same Genes To Multiply within Acanthamoeba castellanii and Human Macrophages. Infect. Immun. 67: 2117-2124 [Abstract] [Full Text]  
• Wiater, L. A., Dunn, K., Maxfield, F. R., Shuman, H. A. (1998). Early Events in Phagosome Establishment Are Required for Intracellular Survival of Legionella pneumophila. Infect. Immun. 66: 4450-4460 [Abstract] [Full Text]  
• Byrne, B., Swanson, M. S. (1998). Expression of Legionella pneumophila Virulence Traits in Response to Growth Conditions. Infect. Immun. 66: 3029-3034 [Abstract] [Full Text]  
• Ratcliff, R. M., Lanser, J. A., Manning, P. A., Heuzenroeder, M. W. (1998). Sequence-Based Classification Scheme for the Genus Legionella Targeting the mip Gene. J. Clin. Microbiol. 36: 1560-1567 [Abstract] [Full Text]  
• Purcell, M., Shuman, H. A. (1998). The Legionella pneumophila icmGCDJBF Genes Are Required for Killing of Human Macrophages. Infect. Immun. 66: 2245-2255 [Abstract] [Full Text]  
• Vogel, J. P., Andrews, H. L., Wong, S. K., Isberg, R. R. (1998). Conjugative Transfer by the Virulence System of Legionella pneumophila. Science 279: 873-876 [Abstract] [Full Text]