Read by QxMD icon Read


A Leoni Swart, Christopher F Harrison, Ludwig Eichinger, Michael Steinert, Hubert Hilbi
Environmental bacteria of the genus Legionella naturally parasitize free-living amoebae. Upon inhalation of bacteria-laden aerosols, the opportunistic pathogens grow intracellularly in alveolar macrophages and can cause a life-threatening pneumonia termed Legionnaires' disease. Intracellular replication in amoebae and macrophages takes place in a unique membrane-bound compartment, the Legionella -containing vacuole (LCV). LCV formation requires the bacterial Icm/Dot type IV secretion system, which translocates literally hundreds of "effector" proteins into host cells, where they modulate crucial cellular processes for the pathogen's benefit...
2018: Frontiers in Cellular and Infection Microbiology
Sophia David, Massimo Mentasti, Julian Parkhill, Victoria J Chalker
OBJECTIVES: Legionella pneumophila is the leading cause of Legionnaires' disease, a severe form of pneumonia acquired from environmental sources. Investigations of both sporadic cases and outbreaks mostly rely on analysis of a single to a few colony pick(s) isolated from each patient. However, due to the lack of data describing diversity within single patients, the optimal number of picks is unknown. Here, we investigated diversity within individual patients using sequence based typing (SBT) and whole genome sequencing (WGS)...
March 13, 2018: Clinical Microbiology and Infection
Tomoko Kubori, Tomoe Kitao, Hiroki Ando, Hiroki Nagai
The intracellular bacterial pathogen Legionella pneumophila establishes the replicative niche as a result of the actions of a large array of effector proteins delivered via the Legionella type IV secretion system (T4SS). Many effector proteins are expected to be involved in biogenesis and regulation of the Legionella-containing vacuole (LCV) that is highly decorated with ubiquitin. Here, we identified a Legionella deubiquitinase (DUB), designated LotA, by carrying out a genome analysis to find proteins resembling the eukaryotic ovarian tumor (OTU) superfamily of cysteine proteases...
March 15, 2018: Cellular Microbiology
Arwa Abu Khweek, Amal O Amer
Legionella pneumophila ( L. pneumophila ) is an opportunistic waterborne pathogen and the causative agent for Legionnaires' disease, which is transmitted to humans via inhalation of contaminated water droplets. The bacterium is able to colonize a variety of man-made water systems such as cooling towers, spas, and dental lines and is widely distributed in multiple niches, including several species of protozoa In addition to survival in planktonic phase, L. pneumophila is able to survive and persist within multi-species biofilms that cover surfaces within water systems...
2018: Frontiers in Cellular and Infection Microbiology
Yehonatan Sharaby, Sarah Rodríguez-Martínez, Marina Pecellin, Rotem Sela, Avi Peretz, Manfred Höfle, Malka Halpern, Ingrid Brettar
Legionella pneumophila causes water-based infections resulting in severe pneumonia. Recently, we showed that different variable numbers of tandem repeat analysis (MLVA-8) genotypes dominated different sites of a drinking-water distribution system, with a genotype-related temperature and abundance regime. Here we compare the pathogenicity potential of different MLVA-8 genotypes of environmental and clinical strains. The virulence traits studied were hemolytic activity and cytotoxicity towards amoebae and macrophages...
March 9, 2018: Applied and Environmental Microbiology
Haihan Zhang, Yue Wang, Shengnan Chen, Zhenfang Zhao, Ji Feng, Zhonghui Zhang, Kuanyu Lu, Jingyu Jia
Urban lakes play a vital role in the sustainable development of urbanized areas. In this freshwater ecosystem, massive microbial communities can drive the recycling of nutrients and regulate the water quality. However, water bacterial and fungal communities in the urban lakes are not well understood. In the present work, scanning electron microscopy (SEM) was combined with community level physiological profiles (CLPPs) and Illumina Miseq sequence techniques to determine the diversity and composition of the water bacterial and fungal community in three urban lakes, namely Xingqing lake (LX), Geming lake (LG) and Lianhu lake (LL), located in Xi'an City (Shaanxi Province, China)...
March 7, 2018: International Journal of Environmental Research and Public Health
Makiko Yoshida, Naoko Furuya, Naoto Hosokawa, Hajime Kanamori, Mitsuo Kaku, Michio Koide, Futoshi Higa, Jiro Fujita
In a tertiary hospital, Legionella spp were isolated from taps and from ward dishwashers connected to contaminated tap piping. Our investigation revealed favorable conditions for growth of Legionella, and showed that Legionella pneumophila SG6 isolates from the taps and dishwashers were all genetically identical by repetitive-element polymerase chain reaction. These results suggest that contaminated dishwashers might be a potential reservoir for the spread of Legionella in health care facilities.
March 1, 2018: American Journal of Infection Control
Huan Li, Shang Li, Wei Tang, Yang Yang, Jianfu Zhao, Siqing Xia, Weixian Zhang, Hong Wang
Secondary water supply systems (SWSSs) refer to the in-building infrastructures (e.g., water storage tanks) used to supply water pressure beyond the main distribution systems. The purpose of this study was to investigate the influence of SWSSs on microbial community structure and the occurrence of opportunistic pathogens, the latter of which are an emerging public health concern. Higher numbers of bacterial 16S rRNA genes, Legionella and mycobacterial gene markers were found in public building taps served by SWSSs relative to the mains, regardless of the flushing practice (P < 0...
February 16, 2018: Water Research
Reyaz A Para, Bashir A Fomda, Rafi A Jan, Sonaullah Shah, Parvaiz A Koul
Background: There is a paucity of literature regarding the microbial etiology of community-acquired pneumonia (CAP) in India. The current study was aimed to study the microbial etiology of hospitalized adults with CAP. Methods: The study was conducted in a 700-bedded North Indian hospital. Consecutive adults admitted with CAP over a period of 2 years from 2013 to 2015 were recruited for the study, and apart from clinical evaluation underwent various microbiological studies in the form of blood culture, sputum culture, urinary antigen for pneumococcus and Legionella, serology for Mycoplasma and Chlamydia and real-time reverse transcriptase polymerase chain reaction for influenza viruses...
March 2018: Lung India: Official Organ of Indian Chest Society
Daniel Gerrity, Mayara Arnold, Eric Dickenson, Duane Moser, Joshua D Sackett, Eric C Wert
Microbial community structure in the ozone-biofiltration systems of two drinking water and two wastewater treatment facilities was characterized using 16S rRNA gene sequencing. Collectively, these datasets enabled comparisons by facility, water type (drinking water, wastewater), pre-oxidation (ozonation, chlorination), media type (anthracite, activated carbon), media depth, and backwash dynamics. Proteobacteria was the most abundant phylum in drinking water filters, whereas Bacteroidetes, Chloroflexi, Firmicutes, and Planctomycetes were differentially abundant in wastewater filters...
February 13, 2018: Water Research
Jayne Watson, Claire Jenkins, Abigail Clements
Shigella flexneri and Shigella sonnei cause the majority of all shigellosis cases worldwide. However their distribution differs with S. sonnei predominating in middle and high-income countries and S. flexneri in low-income countries. One proposed explanation for the continued expansion of S. sonnei is that it can survive in amoebae, which could provide a protective environment for the bacteria. In this study we demonstrate that whilst both S. sonnei and S. flexneri can survive co-culture with the free-living amoebae A...
February 23, 2018: Applied and Environmental Microbiology
Casey P Peterson, Cassidy Sauer, Christa H Chatfield
Human infection by bacteria of the genus Legionella most often result in the pneumonia known as Legionnaires Disease. Legionella is found as a resident of adherent biofilms in man-made water systems. Disinfection efforts to prevent Legionella infections require a better understanding of the structures that promote Legionella surface attachment and biofilm colonization. Various enzymatic treatments, including multiple carbohydrate-targeting mixtures, failed to disrupt Legionella biofilms, despite the presence of carbohydrates in the biofilms as shown by biochemical methods and concanavalin-A lectin staining...
February 21, 2018: Current Microbiology
G Descours, H Hannetel, J V Reynaud, A G Ranc, L Beraud, C Kolenda, C Campese, G Lina, C Ginevra, S Jarraud
The isolation of Legionella from respiratory samples is the gold standard for Legionnaires' disease (LD) diagnosis and enables epidemiological studies and outbreak investigations. The purpose of this work was to adapt and evaluate the performance of an amoebic coculture procedure (the amoebae plate test, APT) to the recovery of Legionella strains from respiratory samples, in comparison with axenic culture and a liquid-based amoebic coculture (LAC). Axenic culture, LAC, and APT were prospectively performed on 133 respiratory samples from patients with LD...
February 21, 2018: Journal of Clinical Microbiology
Zhu Chen, Tong Yang, Haowen Yang, Taotao Li, Libo Nie, Xianbo Mou, Yan Deng, Nongyue He, Zhiyang Li, Lijun Wang, Song Li
This study aimed at developing a portable multi-channel turbidity system (21 cm in length, 15.5 cm in width and 11.5 cm in depth) by real-time loop-mediated isothermal amplification (LAMP) method for rapid detection of pathogens. The developed system herein includes temperature control unit, photoelectric detection unit, turbidity calibration unit, power management unit, human machine unit, communication unit and ARM-based microcontroller. The coefficient of variation for eight channels is less than 0.25% in noise analysis...
January 1, 2018: Journal of Biomedical Nanotechnology
Anke Stüken, Thomas H A Haverkamp, Hubert A A M Dirven, Gregor D Gilfillan, Magnus Leithaug, Vidar Lund
Copper-silver-ionization (CSI) is an in-house water disinfection method primarily installed to eradicate Legionella bacteria from drinking water distribution systems (DWDS). Its effect on the abundance of culturable Legionella and Legionella infections has been documented in several studies. However, the effect of CSI on other bacteria in DWDS is largely unknown. To investigate these effects, we characterised drinking water and biofilm communities in a hospital using CSI, in a neighbouring building without CSI, and in treated drinking water at the local water treatment plant...
February 20, 2018: Environmental Science & Technology
F Carinci, L Scapoli, M Contaldo, R Santoro, A Palmieri, F Pezzetti, D Lauritano, V Candotto, D Mucchi, L Baggi, A Tagliabue, L Tettamanti
Legionella spp. are ubiquitous in aquatic habitats and water distribution systems, including dental unit waterlines. Surveys have shown that the percentage of samples taken at different dental sites that were positive for Legionella spp. were highly variable and ranged from 0% to 100%. Cultivation is the principal approach to evaluating bacterial contamination employed in the past, but applying this approach to testing for Legionella spp. may result in false-negative data or underestimated bacterial counts...
January 2018: Journal of Biological Regulators and Homeostatic Agents
Naoyuki Miyashita, Intetsu Kobayashi, Futoshi Higa, Yosuke Aoki, Toshiaki Kikuchi, Masafumi Seki, Kazuhiro Tateda, Nobuko Maki, Kazuhiro Uchino, Kazuhiko Ogasawara, Satoe Kurachi, Tatsuya Ishikawa, Yoshito Ishimura, Izumo Kanesaka, Hiroshi Kiyota, Akira Watanabe
The activities of various antibiotics against 58 clinical isolates of Legionella species were evaluated using two methods, extracellular activity (minimum inhibitory concentration [MIC]) and intracellular activity. Susceptibility testing was performed using BSYEα agar. The minimum extracellular concentration inhibiting intracellular multiplication (MIEC) was determined using a human monocyte-derived cell line, THP-1. The most potent drugs in terms of MICs against clinical isolates were levofloxacin, garenoxacin, and rifampicin with MIC90 values of 0...
February 17, 2018: Journal of Infection and Chemotherapy: Official Journal of the Japan Society of Chemotherapy
Fatma Gomaa, Maxim Gersh, Colleen Cavanaugh
Diverse species of Legionella and Legionella-like amoebal pathogens (LLAPs) have been identified as intracellular bacteria in many amoeboid protists. There are, however, other amoeboid groups such as testate amoeba for which we know little about their potential to host such bacteria. In this study we assessed the occurrence and diversity of Legionella spp. in cultures and environmental isolates of freshwater arcellinid testate amoebae species, Arcella hemispherica, Arcella intermedia, and Arcella vulgaris, via 16S rRNA gene sequence analyses and fluorescent in situ hybridization (FISH)...
February 14, 2018: Journal of Eukaryotic Microbiology
Maha Farhat, Raja A Shaheed, Haider H Al-Ali, Abdullah S Al-Ghamdi, Ghadeer M Al-Hamaqi, Hawraa S Maan, Zainab A Al-Mahfoodh, Hussain Z Al-Seba
OBJECTIVES: To investigate the presence of Legionella spp in cooling tower water. Legionella proliferation in cooling tower water has serious public health implications as it can be transmitted to humans via aerosols and cause Legionnaires' disease. METHODS: Samples of cooling tower water were collected from King Fahd Hospital of the University (KFHU) (Imam Abdulrahman Bin Faisal University, 2015/2016). The water samples were analyzed by a standard Legionella culture method, real-time polymerase chain reaction (RT-PCR), and 16S rRNA next-generation sequencing...
February 2018: Saudi Medical Journal
Xiaobo Yu, Rebecca R Noll, Barbara P Romero Dueñas, Samual C Allgood, Kristi Barker, Jeffrey L Caplan, Matthias P Machner, Joshua LaBaer, Ji Qiu, M Ramona Neunuebel
BACKGROUND: The intracellular bacterial pathogen Legionella pneumophila proliferates in human alveolar macrophages, resulting in a severe pneumonia termed Legionnaires' disease. Throughout the course of infection, L. pneumophila remains enclosed in a specialized membrane compartment that evades fusion with lysosomes. The pathogen delivers over 300 effector proteins into the host cell, altering host pathways in a manner that sets the stage for efficient pathogen replication. The L. pneumophila effector protein AnkX targets host Rab GTPases and functions in preventing fusion of the Legionella-containing vacuole with lysosomes...
January 5, 2018: BMC Microbiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"