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Ma Amy T AT Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, - - 2009
The type VI secretion system (T6SS) is a virulence mechanism common to several Gram-negative pathogens. In Vibrio cholerae, VgrG-1 is required for T6SS-dependent secretion. VgrG-1 is also secreted by T6SS and displays a C-terminal actin crosslinking domain (ACD). Using a heterologous reporter enzyme in place of the ACD, we show ...
Lu Hsu-Feng - - 2009
Emodin (1,3,8-trihydroxy-6-methylanthaquinone), an active component present in the root and rhizome of Rheum palmatum L. (Polygonaceae) has anti-bacterial, anti-tumor, diuretic and vasorelaxant effects. However, its mechanism of action on the cell migration and invasion of human neuroblastoma cancer SH-SY5Y cells is not fully understood. In this study, firstly, the effects ...
Botteaux A - - 2009
Duox proteins are members of the NADPH oxidase (Nox) family and are responsible for hydrogen peroxide (H(2)O(2)) production by various tissue types including bronchial and intestinal mucosae. The antimicrobial killing role of H(2)O(2) in leukocytes and macrophages is generally considered as the paradigm of its function. We investigated here the ...
Periasamy Saravanan - - 2009
Formation of dental plaque is a developmental process involving initial and late colonizing species that form polymicrobial communities. Fusobacteria are the most numerous gram-negative bacteria in dental plaque, but they become prevalent after the initial commensal colonizers, such as streptococci and actinomyces, have established communities. The unusual ability of these ...
Goulter R M - - 2009
An understanding of the mechanisms which facilitate the attachment of Escherichia coli and other bacterial species to abiotic surfaces is desired by numerous industries including the food and medical industries. Numerous studies have attempted to explain bacterial attachment as a function of bacterial properties such as cellular surface charge, hydrophobicity ...
Corcionivoschi N - - 2009
The host cell environment can alter bacterial pathogenicity. We employed a combination of cellular and molecular techniques to study the expression of Campylobacter jejuni polysaccharides cocultured with HCT-8 epithelial cells. After two passages, the amount of membrane-bound high-molecular-weight polysaccharide was considerably reduced. Microarray profiling confirmed significant downregulation of capsular polysaccharide ...
Chattopadhyay Suddhashil - - 2009
It has been theoretically suggested that when a bacterium swims in a fluid, the disturbance it creates is long-ranged and can influence its locomotion. The contribution of these long-range hydrodynamic interactions to swimming cells is examined herein for a number of bacterial strains with well-defined flagellar geometries. We show experimentally ...
Souza Wanderley de - - 2009
Historically, scientists in Brazil has significantly contributed to the biology, cultivation and structural organization of the pathogenic protozoan Toxoplasma gondii and its interaction with host cells, starting with the description of the protozoan by Splendore in 1908. The intracellular and extracellular corpuscoli observed in rabbits, corresponded to what we now ...
Posfay-Barbe Klara M - - 2009
Listeria monocytogenes, a small, facultative anaerobic, Gram-positive motile bacillus, is an important cause of foodborne illness which disproportionately affects pregnant women and their newborns. Listeria infects many types of animals and contaminates numerous foods including vegetables, milk, chicken and beef. This organism has a unique proclivity to infect the fetoplacental ...
Mostowy Serge - - 2009
Septins are filament-forming GTPases implicated in several cellular functions, including cytokinesis. We previously showed that SEPT2, SEPT9, and SEPT11 colocalize with several bacteria entering into mammalian non-phagocytic cells, and SEPT2 was identified as essential for this process. Here, we investigated the function of SEPT11, an interacting partner of SEPT9 whose ...
Santic Marina - - 2009
Since transmission of Francisella tularensis into the mammalian host occurs via arthropod vectors such as ticks, mosquitoes, horseflies and deerflies, recent studies have established Drosophila melanogaster as an arthropod vector model system. Nothing is known about the intracellular fate of F. tularensis within arthropod-derived cells, and the role of this ...
Huang Guanghua - - 2009
To mate, Candida albicans must undergo homozygosis at the mating type-like locus MTL[1, 2], then switch from the white to opaque phenotype [3, 4]. Paradoxically, when opaque cells are transferred in vitro to 37 degrees C, the temperature of their animal host, they switch en masse to white [5-7], suggesting ...
Fiskesund R - - 2009
AIMS: To prepare 1,5-anhydro-d-fructose (AF) derivatives, test their microbial inhibition spectrum, and to further examine the most effective AF derivative against Pseudomonas aeruginosa and malignant blood cell lines. METHODS AND RESULTS: Microthecin and nine other AF derivatives were synthesized from AF. The 10 compounds were tested in vitro against Gram-positive ...
Harz Michaela - - 2009
Bacterial meningitis is a relevant public health concern. Despite the availability of modern treatment strategies it is still a life-threatening disease that causes significant morbidity and mortality. Therefore, an initial treatment approach plays an important role. For in-time identification of specific bacterial pathogens of the cerebrospinal fluid (CSF) and emerged ...
de Breij Anna - - 2009
Acinetobacter baumannii is a nosocomial pathogen responsible for outbreaks of infection worldwide. The factors associated with its ability to colonize/infect human hosts are largely unknown. Adherence to host cells is the first step in colonization/infection, which can be followed by biofilm formation. A. baumannii ATCC19606(T) biofilm formation on abiotic surfaces ...
Sal-Man Neta - - 2009
Several virulent bacteria have the ability to manipulate the host cell actin cytoskeleton as part of their pathogenic strategy. These pathogens subvert the host cell actin polymerization machinery for various purposes including motility within host cells, cell-to-cell spread, and to prevent phagocytic engulfment by professional phagocytes. In contrast to intracellular ...
Auger Eliane - - 2009
Host-pathogen interactions are of great importance in understanding the pathogenesis of infectious microorganisms. We developed in vitro models to study the host-pathogen interactions of porcine respiratory tract pathogens using two immortalized epithelial cell lines, namely, the newborn pig trachea (NPTr) and St. Jude porcine lung (SJPL) cell lines. We first ...
Morán Xosé Anxelu G - - 2009
The connections between single-cell activity properties of heterotrophic planktonic bacteria and whole community metabolism are still poorly understood. Here, we show flow cytometry single-cell analysis of membrane-intact (live), high nucleic acid (HNA) content and actively respiring (CTC+) bacteria with samples collected monthly during 2006 in northern Spain coastal waters. Bulk ...
Spiliotis Markus - - 2009
Parasitic helminths are a major cause of disease worldwide, yet the molecular mechanisms of host-helminth interaction and parasite development are only rudimentarily studied. A main reasons for this lack of knowledge are the tremendous experimental difficulties in cultivating parasitic helminths under defined laboratory conditions and obtaining sufficient amounts of parasite ...
Tran Van Nhieu Guy - - 2009
During the course of infection, pathogens often induce changes in gene expression in host cells and these changes can be long lasting and global or transient and of limited amplitude. Defining how, when, and why bacterial pathogens reprogram host cells represents an exciting challenge that opens up the opportunity to ...
Buntru Alexander - - 2009
Bacteria-triggered signaling events in infected host cells are key elements in shaping the host response to pathogens. Within the eukaryotic cell, signaling complexes are spatially organized. However, the investigation of protein-protein interactions triggered by bacterial infection in the cellular context is technically challenging. Here, we provide a methodological approach to ...
Watanabe Kenta - - 2009
BACKGROUND: Trophoblast giant (TG) cells are involved in systematic removal of bacterial pathogens from the maternal-fetal interface of the placenta. In particular, TG cells have the ability to take up extracellular antigens by active phagocytosis induced by interferon-gamma (IFN-gamma). We previously reported that heat shock cognate protein 70 (Hsc70) present ...
Boldis V - - 2009
Ultrastructural changes induced by Rickettsia slovaca standard type (ST) and wild type (WT) were examined during their life cycle in L929 and Vero cells. R. slovaca invaded the cytoplasm of the host cell by phagocytosis on the 1st d p.i. Rickettsiae adhering to the cytoplasmic membrane were engulfed by cellular ...
Muschiol Sandra - - 2009
BACKGROUND: Chlamydiae are obligate intracellular pathogens that possess a type III secretion system to deliver proteins into the host cell during infection. Small molecule inhibitors of type III secretion in Yersinia, termed INPs (Innate Pharmaceuticals AB) were reported to strongly inhibit Chlamydia growth in epithelial cells. In this study we ...
Tigyi Z - - 2009
Polarisation optical methods provide the means to perform sub-microscopic investigations on structures containing spatially highly ordered molecules, for example the cell envelope of prokaryotic cells. Such structures can evoke birefringence, which can be enhanced or modified by different dyes or reagents, thus providing the possibility of a more specific investigation ...
Ducret Adrien - - 2009
Most time lapse microscopy experiments studying bacterial processes ie growth, progression through the cell cycle and motility have been performed on thin nutrient agar pads. An important limitation of this approach is that dynamic perturbations of the experimental conditions cannot be easily performed. In eukaryotic cell biology, fluidic approaches have ...
da Silva Neto Benedito Rodrigues - - 2009
The pathogenic fungus Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis (PCM). This is a pulmonary mycosis acquired by inhalation of fungal airborne propagules that can disseminate to several organs and tissues leading to a severe form of the disease. Adhesion and invasion to host cells are essential steps involved in ...
Lee Kuo-Chang - - 2009
The phylum Verrucomicrobia is a divergent phylum within domain Bacteria including members of the microbial communities of soil and fresh and marine waters; recently extremely acidophilic members from hot springs have been found to oxidize methane. At least one genus, Prosthecobacter, includes species with genes homologous to those encoding eukaryotic ...
Subbiahdoss Guruprakash - - 2009
Biomaterial-associated infections constitute a major clinical problem. Unfortunately, microorganisms are frequently introduced onto an implant surface during surgery and start the race for the surface before tissue integration can occur. So far, no method has been forwarded to study biofilm formation and tissue integration simultaneously. The aim of this study ...
Cendron Laura L Department of Chemistry, University of Padua Via Marzolo 1, I-35131 Padua, - - 2009
Pathogenic strains of Helicobacter pylori use a type IV secretion system (T4SS) to deliver the toxin CagA into human host cells. The T4SS, along with the toxin itself, is coded into a genomic insert, which is termed the cag pathogenicity island. The cag pathogenicity island contains about 30 open-reading frames, ...
Choi, Chul
Abstract Background Acinetobacter baumannii is a nosocomial pathogen of increasing importance, but the pathogenic mechanism of this microorganism has not been fully explored. This study investigated the potential of A. baumannii to invade epithelial cells and determined the role of A. baumannii outer membrane protein A (AbOmpA) in interactions with ...
Kubota, Norihiro
Oligobrachia mashikoi, a frenulata, is a marine invertebrate living in an unusual habitat in Tsukumo Bay (20-25m deep), Japan. It lacks a mouth and a gut, and instead possesses specialized cells called bacteriocytes, in which endosymbiotic bacterial cells are kept. The endosymbiosis involves specific interactions and obligatory metabolic exchanges between ...
Lavine Mark D MD Department of Microbiology, Molecular Biology and Biochemistry and Center for Reproductive Biology, University of Idaho, Life Sciences South Room 142, Moscow, ID 83843, - - 2009
The intracellular parasite Toxoplasma gondii extensively modifies its host cell so as to efficiently grow and divide. Among these cellular changes, T. gondii alters the cell cycle of host cells it has invaded. We found that T. gondii affects the cell cycle of not only the cells it directly invades, ...
da Silva Claudio Vieira - - 2009
Toxoplasma gondii infects a variety of different cell types in a range of different hosts. Host cell invasion by T. gondii occurs by active penetration of the host cell, a process previously described as independent of host actin polymerization. Also, the parasitophorous vacuole has been shown to resist fusion with ...
Locsei J T - - 2009
Previously published experimental work by other authors has shown that certain motile marine bacteria are able to track free-swimming algae by executing a zigzag path and steering toward the algae at each turn. Here, we propose that the apparent steering behaviour could be a hydrodynamic effect, whereby an algal cell's ...
Martinez-Argudo Isabel - - 2008
We have used an in vitro model of intestinal M cells to examine the mechanisms by which Salmonella enterica translocates across these specialized cells, which constitute a primary site of infection of the mammalian host. S. enterica can invade cultured cells by deploying a type III secretion system (TTSS) encoded ...
Rickard A H - - 2008
AIMS: We evaluated the ability of a dual-species community of oral bacteria to produce the universal signalling molecule, autoinducer-2 (AI-2), in saliva-fed biofilms. METHODS AND RESULTS: Streptococcus oralis 34, S. oralis 34 luxS mutant and Actinomyces naeslundii T14V were grown as single- and dual-species biofilms within sorbarods fed with 25% ...
Larson Charles L - - 2008
Campylobacter jejuni is a major food-borne bacterial pathogen, which is capable of causing diarrhoea containing blood and leukocytes. C. jejuni invasion of the intestinal epithelial cells and the release of proinflammatory molecules contribute to the pathophysiology of campylobacteriosis. Given the commensal relationship of C. jejuni with chickens, we hypothesized that ...
Chuaygud Tippamas - - 2008
Burkholderia pseudomallei is an agent of melioidosis and is closely related to avirulent B. thailandensis. Burkholderia thailandensis has a 15-bp deletion within the variable region of the flagellin gene fliC compared with B. pseudomallei. The difference in the fliC gene might be related to virulence. In the present study, the ...
Hsiao William W L - - 2008
This article summarizes advances in the field of host-microbe interactions in the gut. The human gut is home to a complex community of microbes (the microbiota) that plays a critical role in host nutrient acquisition and metabolism, development of intestinal epithelial cells, and host immune system. Genetic background, nutritional status, ...
Wine Eytan - - 2008
The precise mechanism by which the most common cause of bacterial enterocolitis in humans, Campylobacter jejuni, perturbs the intestinal mucosa remains elusive. To define effects of C. jejuni infection on mucosal permeability, Madin-Darby canine kidney (MDCK)-I and T84 cell monolayers were infected with C. jejuni for up to 48 h. ...
Gursoy Ulvi Kahraman - - 2008
We examined survival and replication of fusobacteria inside epithelial cells. Subconfluent cultures of HaCaT keratinocytes were infected with five bacterial strains representing three Fusobacterium species: F. nucleatum, F. necrophorum, and F. mortiferum. Adhesion and invasion of the bacteria were assayed before and after antibiotic treatment that killed the adhered and ...
Johnson Jason D JD Department of Developmental and Surgical Sciences, Division of Periodontology, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, - - 2008
The purpose of this study was to test the hypothesis that periodontal pathogens associated with aggressive periodontitis persist in extracrevicular locations following scaling and root planing, systemic antibiotics, and antimicrobial rinses. Eighteen patients with aggressive periodontitis received a clinical examination during which samples of subgingival plaque and buccal epithelial cells ...
de Goffau Marcus C - - 2009
The response of different bacterial species to reduced water availability was studied using a simple relative humidity gradient technique. Interestingly, distinct differences in morphology and growth patterns were observed between populations of the same species growing at different relative humidity. Gram-positive cocci increased in cell size as they approached humidity ...
Yu Jun - - 2009
Embryonic stem (ES) cells are susceptible to genetic manipulation and retain the potential to differentiate into diverse cell types, which are factors that make them potentially attractive cells for studying host-pathogen interactions. Murine ES cells were found to be susceptible to invasion by Salmonella enterica serovar Typhimurium and Shigella flexneri ...
Wang Yubao Y Department of Pathology, Albert Einstein College of Medicine, Bronx, New York 10461, - - 2009
Autophagy has been shown to contribute to defense against intracellular bacteria and parasites. In comparison, the ability of such pathogens to manipulate host cell autophagy to their advantage has not been examined. Here we present evidence that infection by Toxoplasma gondii, an intracellular protozoan parasite, induces host cell autophagy in ...
Sikić Pogacar Maja - - 2009
Although campylobacters are relatively fragile and sensitive to environmental stresses, Campylobacter jejuni has evolved mechanisms for survival in diverse environments, both inside and outside the host. Their survival properties and pathogenic potential were assessed after subjecting food and clinical C. jejuni isolates to different stress conditions. After exposure to starvation ...
Pernagallo Salvatore - - 2009
In this study, polymer microarrays were used for the rapid identification of polymer substrates upon which a suspension cell line would both adhere and proliferate giving a detailed and rapid understanding of cell-biomaterial interactions. Analysis demonstrated that suspension K562 human erythroleukemic cells, which normally grow in suspension, adhered and proliferated ...
Smukalla Scott S FAS Center for Systems Biology, Harvard University, Northwest Labs, Cambridge, MA 02138, - - 2008
The budding yeast, Saccharomyces cerevisiae, has emerged as an archetype of eukaryotic cell biology. Here we show that S. cerevisiae is also a model for the evolution of cooperative behavior by revisiting flocculation, a self-adherence phenotype lacking in most laboratory strains. Expression of the gene FLO1 in the laboratory strain ...
Das Sarita - - 2008
Previous studies on natural products had mainly dealt with their antimicrobial activity and studies on the interference of these bioactive compounds with host-bacterial interaction is limited. The present study was undertaken to investigate the effect of the sterols and fatty acids present in the chloroform fraction of crude methanol extract ...
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