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Shaheen M, Ashbolt NJ. Differential Bacterial Predation by Free-Living Amoebae May Result in Blooms of Legionella in Drinking Water Systems. Microorganisms 2021; 9:microorganisms9010174. [PMID: 33467483 PMCID: PMC7829821 DOI: 10.3390/microorganisms9010174] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/05/2021] [Accepted: 01/12/2021] [Indexed: 11/17/2022] Open
Abstract
Intracellular growth of pathogenic Legionella in free-living amoebae (FLA) results in the critical concentrations that are problematic in engineered water systems (EWS). However, being amoeba-resistant bacteria (ARB), how Legionella spp. becomes internalized within FLA is still poorly understood. Using fluorescent microscopy, we investigated in real-time the preferential feeding behavior of three water-related FLA species, Willaertia magna, Acanthamoeba polyphaga, and Vermamoeba vermiformis regarding Legionella pneumophila and two Escherichia coli strains. Although all the studied FLA species supported intracellular growth of L. pneumophila, they avoided this bacterium to a certain degree in the presence of E. coli and mostly fed on it when the preferred bacterial food-sources were limited. Moreover, once L. pneumophila were intracellular, it inhibited digestion of co-occurring E. coli within the same trophozoites. Altogether, based on FLA–bacteria interactions and the shifts in microbial population dynamics, we propose that FLA’s feeding preference leads to an initial growth of FLA and depletion of prey bacteria, thus increases the relative abundance of Legionella and creates a “forced-feeding” condition facilitating the internalization of Legionella into FLA to initiate the cycles of intracellular multiplication. These findings imply that monitoring of FLA levels in EWS could be useful in predicting possible imminent high occurrence of Legionella.
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Affiliation(s)
- Mohamed Shaheen
- School of Public Health, University of Alberta, Edmonton, AB T6G 1C9, Canada;
| | - Nicholas J. Ashbolt
- School of Environment, Science & Engineering, Southern Cross University, Lismore Campus, PO Box 157, Lismore, NSW 2480, Australia
- Correspondence:
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Studying Hydraulic Interconnections in Low-Permeability Media by Using Bacterial Communities as Natural Tracers. WATER 2020. [DOI: 10.3390/w12061795] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Knowledge about the processes governing subsurface microbial dynamics in and to groundwater represents an important tool for the development of robust, evidence-based policies and strategies to assess the potential impact of contamination sources and for the implementation of appropriate land use and management practices. In this research, we assessed the effectiveness of using microorganisms as natural tracers to analyze subsurface dynamics in a low-permeability system of northern Italy. Microbial communities were investigated through next-generation sequencing of 16S rRNA gene both to study hydraulic interconnections in clayey media and to verify the efficacy of outcropping clayey horizons in protecting groundwater against contamination. During the observation period, a rapid water percolation from the ground surface to the saturated medium was observed, and the mixing between lower-salinity fresh-infiltration waters and higher-salinity groundwater determined the formation of a halocline. This rapid percolation was a driver for the transport of microorganisms from the topsoil to the subsurface, as demonstrated by the presence of soil and rhizosphere bacteria in groundwater. Some of the species detected can carry out important processes such as denitrification or nitrate-reduction, whereas some others are known human pathogens (Legionella pneumophila and Legionella feeleii). These findings could be of utmost importance when studying the evolution of nitrate contamination over space and time in those areas where agricultural, industrial, and civil activities have significantly increased the levels of reactive nitrogen (N) in water bodies but, at the same time, could highlight that groundwater vulnerability of confined or semi-confined aquifers against contamination (both chemical and microbiological) could be higher than expected.
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Long-term persistence of infectious Legionella with free-living amoebae in drinking water biofilms. Int J Hyg Environ Health 2019; 222:678-686. [PMID: 31036480 DOI: 10.1016/j.ijheh.2019.04.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 04/03/2019] [Accepted: 04/18/2019] [Indexed: 11/23/2022]
Abstract
Prolific growth of pathogenic Legionella pneumophila within engineered water systems and premise plumbing, and human exposure to aerosols containing this bacterium results in the leading health burden of any water-related pathogen in developed regions. Ecologically, free-living amoebae (FLA) are an important group of the microbial community that influence biofilm bacterial diversity in the piped-water environment. Using fluorescent microscopy, we studied in-situ the colonization of L. pneumophila in the presence of two water-related FLA species, Willaertia magna and Acanthamoeba polyphaga in drinking water biofilms. During water flow as well as after periods of long-stagnation, the attachment and colonization of L. pneumophila to predeveloped water-biofilm was limited. Furthermore, W. magna and A. polyphaga showed no immediate interactions with L. pneumophila when introduced to the same natural biofilm environment. A. polyphaga encysted within 5-7 d after introduction to the tap-water biofilms and mostly persisted in cysts till the end of the study period (850 d). W. magna trophozoites, however, exhibited a time delay in feeding on Legionella and were observed with internalized L. pneumophila cells after 3 weeks from their introduction to the end of the study period and supported putative (yet limited) intracellular growth. The culturable L.pneumophila in the bulk water was reduced by 2-log over 2 years at room temperature but increased (without a change in mip gene copies by qPCR) when the temperature was elevated to 40 °C within the same closed-loop tap-water system without the addition of nutrients or fresh water. The overall results suggest that L. pneumophila maintains an ecological balance with FLA within the biofilm environment, and higher temperature improve the viability of L. pneumophila cells, and intracellular growth of Legionella is possibly cell-concentration dependent. Observing the preferential feeding behavior, we hypothesize that an initial increase of FLA numbers through feeding on a range of other available bacteria could lead to an enrichment of L. pneumophila, and later force predation of Legionella by the amoeba trophozoites results in rapid intracellular replication, leading to problematic concentration of L. pneumophila in water. In order to find sustainable control options for legionellae and various other saprozoic, amoeba-resisting bacterial pathogens, this work emphasizes the need for better understanding of the FLA feeding behavior and the range of ecological interactions impacting microbial population dynamics within engineered water systems.
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Secreted pyomelanin of Legionella pneumophila promotes bacterial iron uptake and growth under iron-limiting conditions. Infect Immun 2013; 81:4182-91. [PMID: 23980114 DOI: 10.1128/iai.00858-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Iron acquisition is critical to the growth and virulence of Legionella pneumophila. Previously, we found that L. pneumophila uses both a ferrisiderophore pathway and ferrous iron transport to obtain iron. We now report that two molecules secreted by L. pneumophila, homogentisic acid (HGA) and its polymerized variant (HGA-melanin, a pyomelanin), are able to directly mediate the reduction of various ferric iron salts. Furthermore, HGA, synthetic HGA-melanin, and HGA-melanin derived from bacterial supernatants enhanced the ability of L. pneumophila and other species of Legionella to take up radiolabeled iron. Enhanced iron uptake was not observed with a ferrous iron transport mutant. Thus, HGA and HGA-melanin mediate ferric iron reduction, with the resulting ferrous iron being available to the bacterium for uptake. Upon further testing of L. pneumophila culture supernatants, we found that significant amounts of ferric and ferrous iron were associated with secreted HGA-melanin. Importantly, a pyomelanin-containing fraction obtained from a wild-type culture supernatant was able to stimulate the growth of iron-starved legionellae. That the corresponding supernatant fraction obtained from a nonpigmented mutant culture did not stimulate growth demonstrated that HGA-melanin is able to both promote iron uptake and enhance growth under iron-limiting conditions. Indicative of a complementary role in iron acquisition, HGA-melanin levels were inversely related to the levels of siderophore activity. Compatible with a role in the ecology and pathogenesis of L. pneumophila, HGA and HGA-melanin were effective at reducing and releasing iron from both insoluble ferric hydroxide and the mammalian iron chelates ferritin and transferrin.
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5
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Diversity of legionellae strains from Tunisian hot spring water. Res Microbiol 2013; 164:342-50. [DOI: 10.1016/j.resmic.2013.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 01/16/2013] [Indexed: 11/22/2022]
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Yaradou DF, Raze D, Ginevra C, Ader F, Doléans-Jordheim A, Vandenesch F, Menozzi FD, Etienne J, Jarraud S. Zinc-dependent cytoadherence of Legionella pneumophila to human alveolar epithelial cells in vitro. Microb Pathog 2007; 43:234-42. [PMID: 17689220 DOI: 10.1016/j.micpath.2007.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 06/22/2007] [Indexed: 10/23/2022]
Abstract
Microbial adherence to host cells is an early key step in the establishment of infection. During the course of Legionnaire's disease, Legionella interactions with host cells are best documented for resident macrophages. However, L. pneumophila can also replicate within type I and type II pneumocytes, which cover almost the entire alveolar surface. In the presence of zinc, we observed a significant and concentration-dependent increase in L. pneumophila adherence to and invasion of type II pneumocytes. The zinc-dependent adherence mechanism seemed to be host-cell-independent, as a similar increase in cytoadherence was observed with macrophages. We also found that zinc-dependent adherence of L. pneumophila appears to involve recognition of zinc-binding pneumocyte receptors by a bacterial adhesin, and heparan-sulfated host cell receptors, but not type IV pili.
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Chatfield CH, Cianciotto NP. The secreted pyomelanin pigment of Legionella pneumophila confers ferric reductase activity. Infect Immun 2007; 75:4062-70. [PMID: 17548481 PMCID: PMC1951983 DOI: 10.1128/iai.00489-07] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The virulence of Legionella pneumophila is dependent upon its capacity to acquire iron. To identify genes involved in expression of its siderophore, we screened a mutagenized population of L. pneumophila for strains that were no longer able to rescue the growth of a ferrous transport mutant. However, an unusual mutant was obtained that displayed a strong inhibitory effect on the feoB mutant. Due to an insertion in hmgA that encodes homogentisate 1,2-dioxygenase, the mutant secreted increased levels of pyomelanin, the L. pneumophila pigment that is derived from secreted homogentisic acid (HGA). Thus, we hypothesized that L. pneumophila-secreted HGA-melanin has intrinsic ferric reductase activity, converting Fe(3+) to Fe(2+), but that hyperpigmentation results in excessive reduction of iron that can, in the case of the feoB mutant, be inhibitory to growth. In support of this hypothesis, we demonstrated, for the first time, that wild-type L. pneumophila secretes ferric reductase activity. Moreover, whereas the hyperpigmented mutant had increased secreted activity, an lly mutant specifically impaired for pigment production lacked the activity. Compatible with the nature of HGA-melanins, the secreted ferric reductase activity was positively influenced by the amount of tyrosine in the growth medium, resistant to protease, acid precipitable, and heterogeneous in size. Together, these data represent the first demonstration of pyomelanin-mediated ferric reduction by a pathogenic bacterium.
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Affiliation(s)
- Christa H Chatfield
- Department of Microbiology-Immunology, Northwestern University Medical School, 320 East Superior Street, Chicago, IL 60611-3010, USA
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Kuroki H, Miyamoto H, Fukuda K, Iihara H, Kawamura Y, Ogawa M, Wang Y, Ezaki T, Taniguchi H. Legionella impletisoli sp. nov. and Legionella yabuuchiae sp. nov., isolated from soils contaminated with industrial wastes in Japan. Syst Appl Microbiol 2007; 30:273-9. [PMID: 17197147 DOI: 10.1016/j.syapm.2006.11.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In this study, we tried to isolate legionellae from nine Legionella DNA-positive soil samples collected from four different sites contaminated with industrial wastes in Japan. Using culture methods with or without Acanthamoeba culbertsoni, a total of 22 isolates of legionellae were obtained from five of the nine samples. Identification of species and/or serogroups (SGs), performed by DNA-DNA hybridization and agglutination tests, revealed that the 22 isolates consisted of ten isolates of Legionella pneumophila including five SGs, five Legionella feeleii, and one each of Legionella dumoffii, Legionella longbeachae, and Legionella jamestownensis. The species of the remaining four isolates (strains OA1-1, -2, -3, and -4) could not be determined, suggesting that these isolates may belong to new species. The 16S rDNA sequences (1476-1488bp) of the isolates had similarities of less than 95.0% compared to other Legionella species. A phylogenetic tree created by analysis of the 16S rRNA (1270bp) genes demonstrated that the isolates formed distinct clusters within the genus Legionella. Quantitative DNA-DNA hybridization tests on the OA1 strains indicated that OA1-1 should be categorized as a new taxon, whereas OA1-2, -3, and -4 were also genetically independent in another taxon. Based on the evaluated phenotypic and phylogenetic characteristics, it is proposed that one of these isolates from the soils, OA1-1, be classified as a novel species, Legionella impletisoli sp. nov.; the type strain is strain OA1-1(T) (=JCM 13919(T)=DSMZ 18493(T)). The remaining three isolates belong to another novel Legionella species, Legionella yabuuchiae sp. nov.; the type strain is strain OA1-2(T) (=JCM 14148(T)=DSMZ 18492(T)). This is the first report on the isolation of legionellae from soils contaminated with industrial wastes.
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Affiliation(s)
- Hiroko Kuroki
- Department of Microbiology, School of Medicine, University of Occupational and Environmental Health, Fukuoka 807-8555, Japan
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Park MY, Ko KS, Lee HK, Park MS, Kook YH. Legionella busanensis sp. nov., isolated from cooling tower water in Korea. Int J Syst Evol Microbiol 2003; 53:77-80. [PMID: 12656155 DOI: 10.1099/ijs.0.02268-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Three Legionella-like micro-organisms, isolated from cooling tower water of a building in Busan, Korea, were characterized by a variety of biochemical and molecular phylogenetic tests. Analyses of whole-cell fatty acids and results of biochemical tests revealed that these three isolates are distinct from previously described Legionella species. Furthermore, results of comparative analyses of 16S rDNA (1476-1488 bp), mip (408 bp) and rpoB (300 bp) sequences also confirmed that these strains represent a novel species within the genus Legionella. The 16S rDNA sequences of the three Korean isolates had similarities of less than 95.8% to other Legionella species. Phylogenetic trees formed by analysis of the 16S rRNA, rpoB and mip genes revealed that the isolates formed a distinct cluster within the genus Legionella. Based on the evaluated phenotypic and phylogenetic characteristics, it is proposed that these Korean isolates from water be classified as a novel species, Legionella busanensis sp. nov.; the type strain is strain K9951T (=KCTC 12084T =ATCC BAA-518T).
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Affiliation(s)
- Mi-Yeoun Park
- Laboratory of Rickettsial and Zoonotic Disease, Department of Microbiology, Korean National Institute of Health, Seoul 122-701, Korea
| | - Kwan Soo Ko
- Department of Microbiology and Cancer Research Institute, Institute of Endemic Diseases, SNUMRC, Seoul National University College of Medicine and Clinical Research Institute, Seoul National University Hospital, Seoul 110-799, Korea
| | - Hae Kyung Lee
- Laboratory of Rickettsial and Zoonotic Disease, Department of Microbiology, Korean National Institute of Health, Seoul 122-701, Korea
| | - Man-Suk Park
- Laboratory of Rickettsial and Zoonotic Disease, Department of Microbiology, Korean National Institute of Health, Seoul 122-701, Korea
| | - Yoon-Hoh Kook
- Department of Microbiology and Cancer Research Institute, Institute of Endemic Diseases, SNUMRC, Seoul National University College of Medicine and Clinical Research Institute, Seoul National University Hospital, Seoul 110-799, Korea
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Kitsukawa K, Nakamoto A, Koito H, Matsuda Y, Saito A, Yamamoto H. Interferon-gamma (IFN-gamma) production by human T lymphocytes upon Legionella pneumophila stimulation in vitro. Clin Exp Immunol 1995; 99:76-81. [PMID: 7813113 PMCID: PMC1534145 DOI: 10.1111/j.1365-2249.1995.tb03475.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In vitro immune responses to Legionella pneumophila were investigated. When human peripheral blood lymphocytes (PBL) from healthy volunteers were stimulated with formalin-killed L. pneumophila for 7 days in vitro, strong proliferative responses were observed. The responding cells were shown to be a CD4 T cell subset. It was also found that the CD4 T cells secreted significant amounts of IFN-gamma into the PBL culture supernatant. The production of IFN-gamma and IL-4 by PBL was measured semiquantitatively by reverse transcriptase-assisted polymerase chain reaction (RT-PCR) methods. Formalin-killed or live L. pneumophila-stimulated PBL expressed the mRNA for IFN-gamma but not the mRNA for IL-4. The results suggest that the whole bacterium, as opposed to the supernatant, predominantly stimulates Th1 type helper T cells. The cloned T cells specific for L. pneumophila expressed the mRNA for IFN-gamma but not for IL-4. In contrast to formalin-killed or live L. pneumophila stimulation, when PBL were stimulated with the bacterial culture supernatant, the proliferating T cells produced the mRNA for IL-4 as well as for IFN-gamma. A significant correlation between the proliferative response to formalin-killed L. pneumophila and IFN-gamma release in culture was observed (r = 0.6932, P < 0.001) in PBL from 30 healthy volunteers. From these in vitro studies, it is suggested that the whole L. pneumophila bacterium and their soluble antigens stimulate T cells in a manner which results in a different pattern of cytokine production.
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Affiliation(s)
- K Kitsukawa
- Department of Immunology, National Institute of Neuroscience, NCNP, Tokyo, Japan
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Woods TC, McKinney RM, Plikaytis BD, Steigerwalt AG, Bibb WF, Brenner DJ. Multilocus enzyme analysis of Legionella dumoffii. J Clin Microbiol 1988; 26:799-803. [PMID: 3384905 PMCID: PMC266462 DOI: 10.1128/jcm.26.5.799-803.1988] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Variability among 29 clinical and environmental strains of Legionella dumoffii was investigated by multilocus enzyme analysis by use of starch gel electrophoresis. Based on results of analysis at 20 enzyme loci, the strains were separated into five closely related electrophoretic types (ETs), which were clearly distinguished from 53 strains representing 53 ETs of L. pneumophila. DNA hybridization results (hydroxyapatite method, 60 and 75 degrees C) for representative strains confirmed that all L. dumoffii ETs were a single genetic species. Although multilocus enzyme analysis indicated that L. dumoffii was genetically a quite uniform species, sufficient variability existed to warrant electromorph fingerprinting for epidemiologic studies.
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Affiliation(s)
- T C Woods
- Immunology Laboratory, Centers for Disease Control, Atlanta, Georgia 30333
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Berg JD, Hoff JC, Roberts PV, Matin A. Growth of Legionella pneumophila in continuous culture. Appl Environ Microbiol 1985; 49:1534-7. [PMID: 4015091 PMCID: PMC241762 DOI: 10.1128/aem.49.6.1534-1537.1985] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A method was developed to grow Legionella pneumophila in continuous culture. A chemostat was used to simulate nutrient-limited, submaximal growth in the natural environmental and to provide a precisely controlled growth regimen. Cultures grew under forced aeration under conditions yielding up to 38% saturation of dissolved oxygen; supplemental CO2 (5%) at the same gas flow rates as ambient air had no effect on culture growth. Pleomorphism was observed during growth under all conditions. Pigment was produced only at D less than 0.03 h-1. Catalase was produced at higher growth rates but not at higher temperatures. The pathogenicity was unaffected by altering either the growth rate or the growth temperature.
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Klein TW, Friedman H, Widen R. Relative potency of virulent versus avirulent Legionella pneumophila for induction of cell-mediated immunity. Infect Immun 1984; 44:753-5. [PMID: 6724697 PMCID: PMC263693 DOI: 10.1128/iai.44.3.753-755.1984] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Guinea pigs were infected with either high-passage, low-virulence Legionella pneumophila or low-passage, high-virulence organisms. On an infectious dosage basis, the high-virulence organisms were much more effective at sensitizing animals for positive skin test responses and splenic lymphocyte proliferation responses to homologous antigens. These results suggest that exposure to low doses of virulent L. pneumophila can effectively prime animals for cell-mediated immune responses.
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15
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Fliermans CB, Harvey RS. Effectiveness of 1-bromo-3-chloro-5,5-dimethylhydantoin against Legionella pneumophila in a cooling tower. Appl Environ Microbiol 1984; 47:1307-10. [PMID: 6742844 PMCID: PMC240228 DOI: 10.1128/aem.47.6.1307-1310.1984] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cooling towers are considered to be man-made amplifiers of Legionella spp. Thus, the proper maintenance and choice of biocides is important. The only biocidal measure that has thus far been shown to be effective in field tests is the judicious use of chlorination. Perturbation studies with 1-bromo-3-chloro-5, 5-dimethylhydantoin (Bromicide; Great Lakes Chemical Corp., West Lafayette, Ind.) (BCD) were conducted on an industrial cooling tower shown to contain Legionella pneumophila. At the concentrations recommended by the manufacturer, neither the density nor the activity of L. pneumophila was affected. At comcentrations greater than 2.0 ppm (2.0 micorgram/ml) free of residual, BCD was not effective in reducing L. pneumophila to source water concentrations, nor was it effective in reducing the 2-p-iodophenyl-3-p-nitrophenyl-5-phenyl tetrazolium chloride activity of the bacterium in situ. The data indicate that at concentrations up to 2.0 ppm, BCD is not effective in these tower studies.
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Mitchell RG, Pasvol G, Newnham RS. Pneumonia due to Legionella bozemanii: first report of a case in Europe. J Infect 1984; 8:251-5. [PMID: 6736665 DOI: 10.1016/s0163-4453(84)94027-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pneumonia caused by Legionella bozemanii and acquired by a 75-year-old man while on holiday in Majorca is described. This appears to be the first report of such a case from Europe. Despite artificial ventilation and intravenous erythromycin the patient died. The causative organism was isolated from part of the lung obtained post mortem. Examination of a single sample of serum by means of an indirect immunofluorescence test gave a titre of 32 in respect of L. bozemanii antigen.
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Pine L, Hoffman PS, Malcolm GB, Benson RF, Gorman GW. Whole-cell peroxidase test for identification of Legionella pneumophila. J Clin Microbiol 1984; 19:286-90. [PMID: 6365966 PMCID: PMC271040 DOI: 10.1128/jcm.19.2.286-290.1984] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
A simple combined peroxidase-catalase test has been developed which is applicable to live bacterial cells. Known strains of Legionella pneumophila were differentiated from other species of Legionella by being peroxidase positive and catalase negative.
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Abstract
Legionella pneumophila (Lp), serogroups 1-6, was grown in vitro on a variety of media, in embryonated hens' eggs, and in guinea pigs. The morphology of the microbe was examined by light, immunofluorescent, and electron microscopy (transmission, scanning, negative staining). The configuration of all serogroups examined differed somewhat on agar media, in liquid media, and in vivo. Each serogroup of Lp showed pleomorphic features indistinguishable from the others. Except for filamentous forms, pleomorphism was least conspicuous on agar. By contrast, pleomorphism was most apparent in yeast extract broth, and it was detected by all of the morphologic techniques employed. Bacilli were seen most commonly, but the spectrum of forms was as follows: cocci, coccobacilli (short bacilli), medium bacilli, bacilli with terminal cocci, filamentous forms, and branches. Diplococci, branches, and stalks were only rarely seen, and the latter form was never visualized by immunofluorescence. In tissue samples from infected guinea pigs and embryonated hens' eggs, Lp was typically a short bacillus, but coccoid and coccobacillary forms were seen. Lp is clearly a pleomorphic bacterium, particularly when grown in yeast extract broth. The variety of forms described herein might provide clues to taxonomy, ecologic niche, and physiology of Lp.
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Lema M, Brown A. Electrophoretic characterization of soluble protein extracts of Legionella pneumophila and other members of the family Legionellaceae. J Clin Microbiol 1983; 17:1132-40. [PMID: 6874904 PMCID: PMC272814 DOI: 10.1128/jcm.17.6.1132-1140.1983] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The soluble peptides of strains of Legionella pneumophila, Tatlockia micdadei, Fluoribacter bozemanae, Fluoribacter dumoffii, and Fluoribacter gormanii were studied by polyacrylamide gel electrophoresis. Characteristic patterns were seen for Legionella and Tatlockia strains, whereas the patterns for the Fluoribacter strains were variable as would be expected for this genetically heterogeneous group. Grouping by peptide pattern was consistent with proposed taxons based on DNA-DNA homology. By using a new silver stain technique, the sensitivity and ease of pattern recognition were enhanced significantly. This technique is an easily applied general method for distinguishing between strains in epidemiological studies.
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Orrison LH, Cherry WB, Tyndall RL, Fliermans CB, Gough SB, Lambert MA, McDougal LK, Bibb WF, Brenner DJ. Legionella oakridgensis: unusual new species isolated from cooling tower water. Appl Environ Microbiol 1983; 45:536-45. [PMID: 6830217 PMCID: PMC242320 DOI: 10.1128/aem.45.2.536-545.1983] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
We describe a new species of Legionella represented by 10 strains isolated from industrial cooling towers. Legionella oakridgensis differed genetically from the other seven species of Legionella in DNA hybridization studies and differed serologically in direct fluorescent-antibody tests. The new species, unlike all other species except L. jordanis, did not require added L-cysteine for growth in serial transfer on charcoal-yeast extract agar. L. oakridgensis, as well as three other species tested, required L-cysteine for primary isolation from animal tissues. L. oakridgensis was the only species of Legionella that failed to produce alkaline phosphatase at pH 8.5. In all other respects, it resembled other species of Legionella, including having a high content of branched-chain cellular fatty acids and being pathogenic for guinea pigs. These bacteria have not yet been associated with human disease, but they are potential causes of legionellosis.
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Edelstein PH, Pasiecznik KA, Yasui VK, Meyer RD. Susceptibility of Legionella spp. to mycinamicin I and II and other macrolide antibiotics: effects of media composition and origin of organisms. Antimicrob Agents Chemother 1982; 22:90-3. [PMID: 7125633 PMCID: PMC183679 DOI: 10.1128/aac.22.1.90] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Thirty-three strains of Legionella spp., 29 of which were L. pneumophila, were tested for their susceptibilities to erythromycin (EM), rosaramicin, tylosin, mycinamicin I (Sch-27897), and mycinamicin II (Sch-27896). Testing was performed using an agar dilution method with two different types of media: buffered charcoal yeast extract medium supplemented with 0.1% alpha-ketoglutarate (BCYE alpha) and filter-sterilized yeast extract medium with 0.1% alpha-ketoglutarate (BYE alpha). The minimal inhibitory concentrations (MICs) of the drugs tested relative to the MICs of erythromycin were: rosaramicin, MIC approximately equal to 0.2 EM MIC; tylosin, MIC approximately equal to 2 EM MIC; mycinamicin I, MIC approximately equal to 0.5 EM MIC; and mycinamicin II, MIC approximately equal to EM MIC. Both types of media caused equivalent partial inactivation of the macrolides which was apparently due entirely to pH effect. MICs on BCYE alpha were one to five times more than those observed on BYE alpha; this may be due to poorer growth on BYE alpha.
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Cherry WB, Gorman GW, Orrison LH, Moss CW, Steigerwalt AG, Wilkinson HW, Johnson SE, McKinney RM, Brenner DJ. Legionella jordanis: a new species of Legionella isolated from water and sewage. J Clin Microbiol 1982; 15:290-7. [PMID: 7040449 PMCID: PMC272079 DOI: 10.1128/jcm.15.2.290-297.1982] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Legionella jordanis sp. nov., as found in two cultures, is described. One isolate was from river water in Indiana and the other isolate was from sewage in DeKalb County, Ga. The former is the type strain of the species, and is designated BL-540 (ATCC 33623). L. jordanis had a partial relationship to L. bozemanii by direct fluorescent-antibody tests but was unrelated to L. pneumophila, L. dumoffii, L. micdadei, L. gormanii, or L. longbeachae. Legionella phenotypic characteristics, including large amounts of branched-chain cellular fatty acids, were shown by the isolates. Studies of DNA relatedness showed that the two cultures of L. jordanis were only slightly related to the six previously described species of Legionella but were more than 90% related to each other. Indirect fluorescent-antibody tests with human sera suggested that unrecognized human infections with L. jordanis may be occurring.
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