Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heat shock proteins (Hsp) of four Rickettsia species, three Bartonella species, two Ehrlichia species, Orientia tsutsugamushi and seventeen other eubacterial species were characterized by the enhanced chemiluminescence Western blotting (WB) technique with antibodies raised against recombinant Hsp from Escherichia coli and purified GroES from R. typhi. Although E. coli DnaK and GroEL have epitopes that are highly conserved among the homologous proteins found in Rickettsia, Ehrlichia, O. tsutsugamushi, Bartonella and other Proteobacteria, anti-E. coli DnaK and GroEL monoclonal antibodies (Dasch et al. (1990) Ann. N.Y. Acad. Sci. 590, 352-369) recognize less conserved epitopes. In contrast, epitopes on E. coli DnaJ, GrpE and GroES are much less conserved since anti-E. coli DnaJ, GrpE and GroES polyclonal antibodies did not recognize DnaJ, GrpE or GroES homologues in Rickettsia, Bartonella, Orientia, Ehrlichia and Legionella. Polyclonal antiserum prepared against GroES from R. typhi reacted strongly with purified 10 kDa GroES peptide from Rickettsia and Bartonella, and strongly bound to proteins of varying electrophoretic mobility from Wolbachia, Legionella, Proteus and Shigella flexneri and more weakly to other GroES homologues including that found in E. coli. Consequently, commercially available anti-DnaJ, anti-GrpE and anti-GroES polyclonal antibodies and anti-DnaK monoclonal antibody raised against their respective recombinant E. coli Hsp are not suitable for detection and identification of homologues of these proteins in a wide range of eubacteria.
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PMID:Western blotting analysis of heat shock proteins of Rickettsiales and other eubacteria. 980 24

Legionella dumoffii is one of the common causes of Legionnaires' disease and is capable of replicating in macrophages. To understand the mechanism of survival within macrophages, transposon mutagenesis was employed to isolate the genes necessary for intracellular growth. We identified four defective mutants after screening 790 transposon insertion mutants. Two transposon insertions were in genes homologous to icmB or dotC, within dot/icm loci, required for intracellular multiplication of L. pneumophila. The third was in a gene whose product is homologous to the 17-kDa antigen forming part of the VirB/VirD4 type IV secretion system of Bartonella henselae. The fourth was in the djlA (for "dnaj-like A") gene. DjlA is a member of the DnaJ/Hsp40 family. Transcomplementation of the djlA mutant restored the parental phenotype in J774 macrophages, A549 human alveolar epithelial cells, and the amoeba Acanthamoeba culbertsoni. Using confocal laser-scanning microscopy and transmission electron microscopy, we revealed that in contrast to the wild-type strain, L. dumoffii djlA mutant-containing phagosomes were unable to inhibit phagosome-lysosome fusion. Transmission electron microscopy also showed that in contrast to the virulent parental strain, the djlA mutant was not able to recruit host cell rough endoplasmic reticulum. Furthermore, the stationary-phase L. dumoffii djlA mutants were more susceptible to H2O2, high osmolarity, high temperature, and low pH than was their parental strain. These results indicate that DjlA is required for intracellular growth and organelle trafficking, as well as bacterial resistance to environmental stress. This is the first report demonstrating that a single DjlA-deficient mutant exhibits a distinct phenotype.
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PMID:Legionella dumoffii DjlA, a member of the DnaJ family, is required for intracellular growth. 1515 69

DjlA is an inner membrane cochaperone belonging to the DnaJ family, which has been shown to be involved in Legionella sp. pathogenesis. In this study, we explored the role of this protein in the physiology and virulence of Vibrio tapetis, the etiological agent of brown ring disease (BRD) in Manila clam (Ruditapes philippinarum). Analysis of the djlA locus in V. tapetis revealed a putative organization in an operon with a downstream gene that we designated duf924(Vt), which encodes a conserved protein with an unknown function and has homologues in bacteria and eukaryotes. djlA mutants displayed a reduced growth rate and showed an important loss of cytotoxic activity against R. philippinarum hemocytes in vitro, which could be restored by extrachromosomal expression of wild-type djlA(Vt) but not duf924(Vt). These results are in keeping with the potential importance of DjlA for bacterial pathogenicity and open new perspectives for understanding the mechanism of action of this protein in the novel V. tapetis-R. philippinarum interaction model.
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PMID:DjlA, a membrane-anchored DnaJ-like protein, is required for cytotoxicity of clam pathogen Vibrio tapetis to hemocytes. 1864 Nov 67