| interactions of pseudomonas aeruginosa and corynebacterium spp. with non-phagocytic brain microvascular endothelial cells and phagocytic acanthamoeba castellanii. | several lines of evidence suggest that acanthamoeba interact with bacteria, which may aid in pathogenic bacterial transmission to susceptible hosts, and these interactions may have influenced evolution of bacterial pathogenicity. in this study, we tested if gram-negative pseudomonas aeruginosa and gram-positive corynebacterium spp. can associate/invade and survive inside acanthamoeba castellanii trophozoites and cysts, as well as non-phagocytic human brain microvascular endothelial cells. the re ... | 2015 | 25792227 |
| the role of g protein coupled receptor-mediated signaling in the biological properties of acanthamoeba castellanii of the t4 genotype. | despite advances in antimicrobial chemotherapy and supportive care, the prognosis of acanthamoeba infections remains poor, suggesting that new targets are needed that can affect parasite survival and host-pathogen interactions. g proteins and their coupled receptors are well known regulators of a variety of cellular functions. the overall aim of the present study was to study the role of g-protein coupled receptor, β adrenergic receptor on the biology and pathogenesis of keratitis isolate of aca ... | 2015 | 25769819 |
| photochemotherapeutic strategy against acanthamoeba infections. | acanthamoeba is a protist pathogen that can cause serious human infections, including blinding keratitis and a granulomatous amoebic encephalitis that almost always results in death. the current treatment for these infections includes a mixture of drugs, and even then, a recurrence can occur. photochemotherapy has shown promise in the treatment of acanthamoeba infections; however, the selective targeting of pathogenic acanthamoeba has remained a major concern. the mannose-binding protein is an i ... | 2015 | 25753633 |
| acanthamoeba castellanii proteases are capable of degrading iron-binding proteins as a possible mechanism of pathogenicity. | acanthamoeba castellanii, a free-living amoeba, is an amphizoic organism that can behave as an opportunistic pathogen, causing granulomatous amoebic encephalitis in immunocompromised patients or infecting immunocompetent individuals via cutaneous lesions, sinusoidal infections, or amoebic keratitis. therefore, this amoeba could be in contact with different iron-binding proteins, such as lactoferrin in tears and mucosa and transferrin and hemoglobin in blood. iron is a vital and necessary element ... | 2015 | 25737266 |
| statins and voriconazole induce programmed cell death in acanthamoeba castellanii. | members of the genus acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. in order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. we must also avoid toxicity of host tissue. many drugs which target eukaryotes are known to induce programm ... | 2015 | 25733513 |
| [evaluation of in vitro efficacy of combined riboflavin and ultraviolet-a (365 nm) for acanthamoeba]. | acanthamoeba keratitis is a rare but serious disease and is particularly difficult to treat when the diagnosis is delayed, partly because of the limitations of current therapies. the purpose of our study is to evaluate the anti-amoebic effectiveness of riboflavin and uv-a on acanthamoeba castellani. | 2015 | 25637236 |
| molecular cloning and expression of phosphoglycerate dehydrogenase and phosphoserine aminotransferase in the serine biosynthetic pathway from acanthamoeba castellanii. | free-living amoebae of the genus acanthamoeba are widespread protozoans that can cause serious infectious diseases. this study characterised phosphoglycerate dehydrogenase (pgdh) and phosphoserine aminotransferase (psat) in the phosphorylated serine biosynthetic pathway of acanthamoeba castellanii. the pgdh gene encodes a protein of 442 amino acids with a calculated molecular weight of 47.7 kda and an isoelectric point (pi) of 7.64. meanwhile, the psat gene encodes a protein of 394 amino acids w ... | 2015 | 25622549 |
| prevalence of simkania negevensis in chlorinated water from spa swimming pools and domestic supplies. | this study aimed to investigate the prevalence of simkania negevensis in the chlorinated water of spa swimming pools and domestic network systems. | 2015 | 25619531 |
| potent antimicrobial peptides against legionella pneumophila and its environmental host, acanthamoeba castellanii. | legionella pneumophila, the major causative agent of legionnaires' disease, is most often found in the environment in close association with free-living amoebae, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. in the present study, we evaluated the anti-legionella and anti-acanthamoeba activities of three alpha-helical antimicrobial peptides (amps), namely, nk-2, ci-mam-a24, and ci-pap-a22, already known for the extraordinary efficacy against other mi ... | 2015 | 25592737 |
| the acanthamoeba shikimate pathway has a unique molecular arrangement and is essential for aromatic amino acid biosynthesis. | the shikimate pathway is the only known biosynthetic route for de novo synthesis of aromatic compounds. it is described as an ancient eukaryotic innovation that has been retained in a subset of eukaryotes, replaced in plants through the acquisition of the chloroplast, but lost in many including humans. herein, we demonstrate that acanthamoeba castellanii possesses the shikimate pathway by biochemical and a combination of bioinformatics and molecular biological methods. the growth of a. castellan ... | 2015 | 25576842 |
| surfactin from bacillus subtilis displays an unexpected anti-legionella activity. | a contaminant bacterial strain was found to exhibit an antagonistic activity against legionella pneumophila, the causative agent of legionnaires' disease. the bacterial strain was identified as a bacillus subtilis and named b. subtilis am1. pcr analysis revealed the presence of the sfp gene, involved in the biosynthesis of surfactin, a lipopeptide with versatile bioactive properties. the bioactive substances were extracted from am1 cell-free supernatant with ethyl acetate and purified using reve ... | 2015 | 25573468 |
| tigecycline inhibits proliferation of acanthamoeba castellanii. | acanthamoeba is an opportunistic protozoan parasite responsible for different diseases in humans, such as granulomatous amoebic encephalitis and amoebic keratitis. tigecycline, a third-generation tetracycline antibiotic, has potential activity to treat most of the antibiotic resistant bacterial infections. the effects of tigecycline in eukaryotic cells as well as parasites are less well studied. in the present study, we tested the effects of tigecycline on trophozoites of acanthamoeba castellani ... | 2015 | 25563616 |
| top-down effects of a lytic bacteriophage and protozoa on bacteria in aqueous and biofilm phases. | lytic bacteriophages and protozoan predators are the major causes of bacterial mortality in natural microbial communities, which also makes them potential candidates for biological control of bacterial pathogens. however, little is known about the relative impact of bacteriophages and protozoa on the dynamics of bacterial biomass in aqueous and biofilm phases. here, we studied the temporal and spatial dynamics of bacterial biomass in a microcosm experiment where opportunistic pathogenic bacteria ... | 2014 | 25512841 |
| life without post-transcriptional addition of g-1: two alternatives for trnahis identity in eukarya. | the identity of trna(his) is strongly associated with the presence of an additional 5'-guanosine residue (g-1) in all three domains of life. the critical nature of the g-1 residue is underscored by the fact that two entirely distinct mechanisms for its acquisition are observed, with cotranscriptional incorporation observed in bacteria, while post-transcriptional addition of g-1 occurs in eukarya. here, through our investigation of eukaryotes that lack obvious homologs of the post-transcriptional ... | 2015 | 25505023 |
| caspase-like proteins: acanthamoeba castellanii metacaspase and dictyostelium discoideum paracaspase, what are their functions? | caspases are cysteine proteases that are important regulators of programmed cell death in animals. two novel relatives to members of the caspase families metacaspases and paracaspase have been discovered. metacaspase type-1 was identified in acanthamoeba castellanii, an opportunistic protozoan parasite that causes severe diseases in humans. paracaspase was found in the non-pathogenic protozoan dictyostelium discoideum. since their discovery in acanthamoeba and dictyostelium, metacaspases and par ... | 2014 | 25431419 |
| genotyping of acanthamoeba t15: the environmental strain in turkey. | environmental sources are potential sources for the transmission of acanthamoeba in humans and other mammals. | 2015 | 25424836 |
| legionella norrlandica sp. nov., isolated from the biopurification systems of wood processing plants. | fourteen isolates of an unknown species identified as belonging to the genus legionella by selective growth on bcye agar were isolated from the biopurification systems of three different wood processing plants. the mip gene sequence of all 14 isolates was identical and a close match alignment revealed 86 % sequence similarity with legionella pneumophila serogroup 8. the whole genome of isolate legn(t) was sequenced, and a phylogenetic tree based on the alignment of 16s rrna, mip, rpob, rnpb and ... | 2015 | 25406235 |
| partial characterization of acanthamoeba castellanii (t4 genotype) dnase activity. | the deoxyribonuclease (dnase) activities of acanthamoeba castellanii belonging to the t4 genotype were investigated. using zymographic assays, the dnase activities had approximate molecular masses of 25 and 35 kda. a. castellanii dnases exhibited activity at wide-ranging temperature of up to 60 °c and at ph ranging from 4 to 9. the dnases activities were unaffected by proteinase-k treatment, divalent cations such as ca(++), cu(++), mg(++), and zn(++), or divalent cation chelating agent ethylened ... | 2015 | 25358239 |
| the megavirus chilensis cu,zn-superoxide dismutase: the first viral structure of a typical cellular copper chaperone-independent hyperstable dimeric enzyme. | giant viruses able to replicate in acanthamoeba castellanii penetrate their host through phagocytosis. after capsid opening, a fusion between the internal membranes of the virion and the phagocytic vacuole triggers the transfer in the cytoplasm of the viral dna together with the dna repair enzymes and the transcription machinery present in the particles. in addition, the proteome analysis of purified mimivirus virions revealed the presence of many enzymes meant to resist oxidative stress and con ... | 2015 | 25355875 |
| status of the effectiveness of contact lens solutions against keratitis-causing pathogens. | the aim of this study was to assess the antimicrobial effects of marketed contact lens disinfecting solutions. | 2015 | 25280981 |
| influence of the pdms substrate stiffness on the adhesion of acanthamoeba castellanii. | mechanosensing of cells, particularly the cellular response to substrates with different elastic properties, has been discovered in recent years, but almost exclusively in mammalian cells. much less attention has been paid to mechanosensing in other cell systems, such as in eukaryotic human pathogens. | 2014 | 25247122 |
| temperature limitation may explain the containment of the trophozoites in the cornea during acanthamoeba castellanii keratitis. | acanthamoeba keratitis is a serious sight-threatening disease. the relatively low temperature of the cornea may explain why amoebic infections usually are localized in this tissue and rarely spread to other parts of the eye. in this study, the growth rate of the amoeba acanthamoeba castellanii was examined at different temperatures. the aim was to establish the optimal growth temperature for a. castellanii and to examine the growth within the vicinity of the core body temperature. the growth rat ... | 2014 | 25204727 |
| homeostasis of n-α-terminal acetylation of esxa correlates with virulence in mycobacterium marinum. | the mycobacterial esx-1 (esat-6 system 1) exporter translocates virulence factors across the cytoplasmic membrane to the cell wall, cell surface, and the bacteriological medium in vitro. the mechanisms underlying substrate targeting to distinct locations are unknown. several esx-1 substrates are n-α-terminally acetylated. the role of this rare modification in bacteria is unclear. we sought to identify genes required for esx-1 substrate modification, transport, and localization. pathogenic mycoba ... | 2014 | 25135684 |
| chloroquine has a cytotoxic effect on acanthamoeba encystation through modulation of autophagy. | encystation of acanthamoeba castellanii is associated with resistance to chemotherapeutic agents. blocking the encystation process could potentiate the efficacy of chemotherapeutic agents and biocides. during encystation, autophagy is highly stimulated and required for proper encystation of acanthamoeba. in this study, the cytotoxic effect of chloroquine, a well-known autophagy-inhibitory drug, was tested in a. castellanii. chloroquine was able to selectively reduce cell survival during the ency ... | 2014 | 25114131 |
| external nad(p)h dehydrogenases in acanthamoeba castellanii mitochondria. | the mitochondrial respiratory chain of plants and some fungi contains multiple rotenone-insensitive nad(p)h dehydrogenases, of which at least two are located on the outer surface of the inner membrane (i.e., external nadh and external nadph dehydrogenases). annotated sequences of the putative alternative nad(p)h dehydrogenases of the protozoan acanthamoeba castellanii demonstrated similarity to plant and fungal sequences. we also studied activity of these dehydrogenases in isolated a. castellani ... | 2014 | 25113830 |
| atomic force microscopic imaging of acanthamoeba castellanii and balamuthia mandrillaris trophozoites and cysts. | light microscopy and electron microscopy have been successfully used in the study of microbes, as well as free-living protists. unlike light microscopy, which enables us to observe living organisms or the electron microscope which provides a two-dimensional image, atomic force microscopy provides a three-dimensional surface profile. here, we observed two free-living amoebae, acanthamoeba castellanii and balamuthia mandrillaris under the phase contrast inverted microscope, transmission electron m ... | 2015 | 25041405 |
| lethal effects of helianthemum lippii (l.) on acanthamoeba castellanii cysts in vitro. | acanthamoeba spp. commonly cause acanthamoeba keratitis which is typically associated with the wear of contact lenses. therefore, finding an economic, efficient, and safe therapy of natural origin is of outmost importance. this study examined the in vitro lethal potential of ethyl acetate and methanol extracts of helianthemum lippii (l.) (sun roses) against acanthamoeba castellanii cysts isolated from patients with amoebic keratitis. both extracts proved to be potent as regard to their lethal ef ... | 2014 | 25031463 |
| compositional complexity of the mitochondrial proteome of a unicellular eukaryote (acanthamoeba castellanii, supergroup amoebozoa) rivals that of animals, fungi, and plants. | we present a combined proteomic and bioinformatic investigation of mitochondrial proteins from the amoeboid protist acanthamoeba castellanii, the first such comprehensive investigation in a free-living member of the supergroup amoebozoa. this protist was chosen both for its phylogenetic position (as a sister to animals and fungi) and its ecological ubiquity and physiological flexibility. we report 1033 a. castellanii mitochondrial protein sequences, 709 supported by mass spectrometry data (676 n ... | 2014 | 25026440 |
| amoebozoa possess lineage-specific globin gene repertoires gained by individual horizontal gene transfers. | the amoebozoa represent a clade of unicellular amoeboid organisms that display a wide variety of lifestyles, including free-living and parasitic species. for example, the social amoeba dictyostelium discoideum has the ability to aggregate into a multicellular fruiting body upon starvation, while the pathogenic amoeba entamoeba histolytica is a parasite of humans. globins are small heme proteins that are present in almost all extant organisms. although several genomes of amoebozoan species have b ... | 2014 | 25013378 |
| identification of unusual phospholipid fatty acyl compositions of acanthamoeba castellanii. | acanthamoeba are opportunistic protozoan pathogens that may lead to sight-threatening keratitis and fatal granulomatous encephalitis. the successful prognosis requires early diagnosis and differentiation of pathogenic acanthamoeba followed by aggressive treatment regimen. the plasma membrane of acanthamoeba consists of 25% phospholipids (pl). the presence of c20 and, recently reported, 28- and 30-carbon fatty acyl residues is characteristic of amoeba pl. a detailed knowledge about this unusual p ... | 2014 | 25007336 |
| eluding anaphylaxis allows peptide-specific prevention of the relapsing stage of experimental autoimmune encephalomyelitis. | we have used a peptide derived from acanthamoeba castellanii (aca) to treat the relapsing phase of eae that develops in sjl mice following immunization with the plp 139-151 peptide. the native sequence of the aca 81-95 peptide that shares key residues with the plp 139-151 peptide is weakly encephalitogenic in sjl mice but is not recognized by antiserum from sjl mice immunized with plp 139-151. a single amino acid change to the aca 81-95 peptide sequence significantly enhanced its encephalitogeni ... | 2014 | 24997489 |
| characterization of cyst and trophozoite proteins of environmental isolates of acanthamoeba castellanii by two-dimensional gel electrophoresis. | acanthamoeba castellanii has been known to possess pathogenic properties, such as acanthamoebic keratitis and granulomatous amoebic encephalitis. the role of proteases and proteins in the pathogenesis of these infections is still poorly understood. as acanthamoeba sp is a ubiquitous protozoon found in the natural environment they can potentially cause human infections. this study characterized cyst and trophozoite proteins of 3 environmental a. castellanii isolates in comparison with a clinical ... | 2014 | 24968664 |
| in vitro effects of selected contact lens care solutions on acanthamoeba castellanii strains in poland. | free-living, cosmopolitan amoebae of the acanthamoeba genus may be the causative agents of acanthamoeba keratitis (ak) - a progressive, vision-threatening infection of the human cornea described particularly among contact lens wearers. use of contact lens care solutions, effective against these organisms, is important in preventing ak infections. 3 different strains of acanthamoeba castellanii of the t4 genotype (neff strain and two others, isolated from patients with ak) were exposed to 4 selec ... | 2014 | 24967738 |
| protease-activated receptor 2 (par2) is upregulated by acanthamoeba plasminogen activator (apa) and induces proinflammatory cytokine in human corneal epithelial cells. | acanthamoeba plasminogen activator (apa) is a serine protease elaborated by acanthamoeba trophozoites that facilitates the invasion of trophozoites to the host and contributes to the pathogenesis of acanthamoeba keratitis (ak). the aim of this study was to explore if apa stimulates proinflammatory cytokine in human corneal epithelial (hce) cells via the protease-activated receptors (pars) pathway. | 2014 | 24876278 |
| functional expression of the acanthamoeba castellanii alternative oxidase in escherichia coli; regulation of the activity and evidence for acaox gene function. | to evidence acanthamoeba castellanii alternative oxidase (acaox) gene product function, we studied alterations in the levels of mrna and protein and acaox activity during growth in amoeba batch culture. moreover, heterologous expression of acaox in aox-deficient escherichia coli confirmed by the protein immunodetection and functional studies was performed. despite the presence of native bo and bd quinol oxidases in e. coli membrane, from which the latter is known to be cyanide-resistant, functio ... | 2014 | 24860925 |
| amoebicidal efficacy of a novel multi-purpose disinfecting solution: first findings. | free-living amoebae of the genus acanthamoeba can cause a sight-threatening corneal infection, acanthamoeba keratitis, mostly in contact lens wearers. the use of ineffective contact lens disinfecting solutions is one of the most important risk factors for this infection. this study concerns a new multi-purpose contact lens disinfecting solution, opti-free® puremoist®, tested for its efficacy against acanthamoeba trophozoites and cysts by using the most probable number technique for amoebic enume ... | 2014 | 24858922 |
| down-regulation of cellulose synthase inhibits the formation of endocysts in acanthamoeba. | acanthamoeba cysts are resistant to unfavorable physiological conditions and various disinfectants. acanthamoeba cysts have 2 walls containing various sugar moieties, and in particular, one third of the inner wall is composed of cellulose. in this study, it has been shown that down-regulation of cellulose synthase by small interfering rna (sirna) significantly inhibits the formation of mature acanthamoeba castellanii cysts. calcofluor white staining and transmission electron microscopy revealed ... | 2014 | 24850955 |
| the effect of environmental and physiological conditions on excystation of acanthamoeba castellanii belonging to the t4 genotype. | excystation in acanthamoeba is an important property for the onset of infection as well as infection recurrence, post-treatment. the overall aim of this study was to determine the effects of several environmental and physiological parameters on excystation in acanthamoeba castellanii belonging to the t4 genotype. cysts were prepared by inoculating a. castellanii trophozoites on non-nutrient agar plates for up to 2 weeks. to determine the effects of various conditions on excystation, a. castellan ... | 2014 | 24832816 |
| combined drug therapy in the management of granulomatous amoebic encephalitis due to acanthamoeba spp., and balamuthia mandrillaris. | granulomatous amoebic encephalitis (gae) is caused by two protist pathogens, acanthamoeba spp., and balamuthia mandrillaris. although rare, it almost always results in death. in the present study, amoebae were treated with various combinations of clinically-approved drugs, targeting vital cellular receptors and biochemical pathways. the results revealed that among the seven different combinations tested, three proved highly effective against both acanthamoeba castellanii as well as b. mandrillar ... | 2014 | 24726699 |
| encystment in acanthamoeba castellanii: a review. | differentiation of acanthamoeba castellanii trophozoites involves massive turnover of cellular components and remodelling of organelle structure and function so as to produce a cryptobiotic cell, resistant to desiccation, heat, freezing, and chemical treatments. this review presents a summary of a decade of research on the most studied aspects of the biochemistry of this process, with emphasis on problems of biocide and drug resistances, putative new targets, molecular and cell biology of the pr ... | 2014 | 24726698 |
| bioassay guided isolation and identification of anti-acanthamoeba compounds from tunisian olive leaf extracts. | pathogenic acanthamoeba strains are causative agents of granulomatous amoebic encephalitis (gae) and acanthamoeba keratitis (ak) worldwide. the existence of the cyst stage complicates acanthamoeba therapy as it is highly resistant to antibiotics and physical agents. the aim of this study was to investigate the activity of limouni olive leaf cultivar against the trophozoite stage of acanthamoeba. the ethyl acetate and methanol extracts of this variety were tested against acanthamoeba castellanii ... | 2014 | 24726697 |
| in vitro inhibition of protease-activated receptors 1, 2 and 4 demonstrates that these receptors are not involved in an acanthamoeba castellanii keratitis isolate-mediated disruption of the human brain microvascular endothelial cells. | granulomatous amoebic encephalitis is a rare but serious human disease leading almost always to death. the pathophysiology of amoebic encephalitis is better understood, while events leading to the constitution of brain infection are largely unknown. traversal of the blood-brain barrier is a key step in amoebae invasion of the central nervous system and facilitated by amoebic extracellular proteases. by using specific inhibitors of protease-activated receptors 1, 2 and 4, here we studied the role ... | 2014 | 24703976 |
| silicone hydrogel contact lenses surface promote acanthamoeba castellanii trophozoites adherence: qualitative and quantitative analysis. | to describe the adhesion properties of acanthamoeba castellanii trophozoites to silicone hydrogel contact lenses of first generation (lotrafilcon a), second generation (galyfilcon a), and third generation (comfilcon a) and correlate the results with their specific surface characteristics, time of interaction, and suspension media. | 2014 | 24699779 |
| inefficacy of marketed contact lens disinfection solutions against keratitis-causing acanthamoeba castellanii belonging to the t4 genotype. | the aim of this study was to assess the anti-amoebic effects of marketed contact lens disinfecting solutions. using amoebistatic, amoebicidal, and cysticidal assays, nine different contact lens solutions were tested including: renu multiplus, duraplus, ultimate plus, optifree replenish, optifree express, kontex clean, kontex normal, kontex multisol extra+, kontex soak. in vitro growth inhibition (amoebistatic) assays were performed by incubating acanthamoeba castellanii with aforementioned conta ... | 2014 | 24657584 |
| mechanisms associated with phagocytosis of arcobacter butzleri by acanthamoeba castellanii. | acanthamoeba castellanii is a free-living amoeba widely found in environmental matrices such as soil and water. arcobacter butzleri is an emerging potential zoonotic pathogen that can be isolated from environmental water sources, where they can establish endosymbiotic relationships with amoebas. the aim of this study was to describe the implication of mannose-binding proteins and membrane-associated receptors of glucose and galactose present in the amoebic membrane, during the attachment of arco ... | 2014 | 24652445 |
| cytotoxic effect of organic solvents and surfactant agents on acanthamoeba castellanii cysts. | acanthamoeba castellanii is a protozoan parasite that may cause sight-threatening keratitis in some individuals. its eradication is difficult because the trophozoites encyst making organisms highly resistant to anti-amoebic drugs. to test new anti-acanthamoeba agents, usually having low water solubility, organic solvents and surfactant agents should be used. therefore, the lethal effect of different concentrations of the solvents acetone, methanol, ethanol, and dmso and surfactant agents tween 2 ... | 2014 | 24638907 |
| development of a modified gentamicin protection assay to investigate the interaction between campylobacter jejuni and acanthamoeba castellanii atcc 30010. | campylobacter jejuni is one of the leading causes of diarrheal illness worldwide. it is persistent in the environment and on poultry despite its microaerophilic nature and sensitivity to dessication and ph. studies have demonstrated that c. jejuni co-incubated with acanthamoeba spp. may be protected from harmful environmental factors. research in this area, however has included a range of different methodologies for co-incubation, recovery of bacteria and amoebae, and verification of internaliza ... | 2014 | 24632191 |
| acanthamoeba release compounds which promote growth of listeria monocytogenes and other bacteria. | listeria monocytogenes can grow as a saphrophyte in diverse habitats, e.g., soil, rivers, lakes, and on decaying plant material. in these environments, the bacteria are frequently exposed to predatory protozoa such as acanthamoeba. although l. monocytogenes is a facultative intracellular pathogen it does not infect or survive intracellular in acanthamoeba castellanii, unlike several other facultative intracellular bacteria. instead, motile l. monocytogenes can form large aggregates on amoebal ce ... | 2014 | 24562324 |
| failure of chemotherapy in the first reported cases of acanthamoeba keratitis in pakistan. | acanthamoeba keratitis is a painful and progressive infection of the cornea that can result in loss of vision. here, for the first time in pakistan, we report two cases of acanthamoeba keratitis. the first patient was a 37-year-old female who presented with severe itching, redness, pain, along with loss of vision. the patient was a regular soft contact lens wearer. the second patient was a 25-year-old female who had been using soft contact lenses for the past two years. she presented with a burn ... | 2014 | 24548160 |
| the chlamydial organism simkania negevensis forms er vacuole contact sites and inhibits er-stress. | most intracellular bacterial pathogens reside within membrane-surrounded host-derived vacuoles. few of these bacteria exploit membranes from the host's endoplasmic reticulum (er) to form a replicative vacuole. here, we describe the formation of er-vacuole contact sites as part of the replicative niche of the chlamydial organism simkania negevensis. formation of er-vacuole contact sites is evolutionary conserved in the distantly related protozoan host acanthamoeba castellanii. simkania growth is ... | 2014 | 24528559 |
| acanthamoeba and bacteria produce antimicrobials to target their counterpart. | in the microbial ecosystem, microbes compete for space and nutrients. consequently, some have developed the ability to kill or inhibit the growth of other competing microbes by producing antimicrobial substances. as the 'producer' species are generally immune to these substances, their compounds act on the competing microbial species and give the producer more space and access to nutrients for growth. many currently used antibiotics were developed by exploiting this potential of certain microbes ... | 2014 | 24479709 |
| biochemical and cellular mechanisms regulating acanthamoeba castellanii adherence to host cells. | free-living amoebae belonging to the genus acanthamoeba are the causative agents of infections such as amoebic keratitis (ak), granulomatous amoebic encephalitis (gae) and cutaneous lesions. the mechanisms involved in the establishment of infection are unknown. however, it is accepted that the initial phase of pathogenesis involves adherence to the host tissue. in this work, we analysed surface molecules with an affinity for epithelial and neuronal cells from the trophozoites of acanthamoeba cas ... | 2014 | 24476561 |
| identification and quantification of the acanthamoeba species and genotypes from reservoirs in taiwan by molecular techniques. | the occurrence of acanthamoeba was investigated from 21 main reservoirs of taiwan with 12 (57.1%) testing positive. analysis of the 18s rrna gene pcr product was performed in order to identify the acanthamoeba isolates. acanthamoeba spp. concentrations were determined according to taqman real-time qpcr. acanthamoeba genotypes of all isolates were identified t4. the species were categorized to acanthamoeba culbertsoni, acanthamoeba polyphaga, acanthamoeba castellanii and acanthamoeba hatchetti. t ... | 2014 | 24388954 |
| the evaluation of the amebicidal activity of eryngium planum extracts. | selected fractions of ethanolic extracts obtained from leaves and roots of eryngium planum (apiaceae) were evaluated in vitro for amebicidal activity against acanthamoeba castellanii. this free-living ameba is the cause of acanthamoeba keratitis, which is a painful, vision-impairing disease of the eyes, and chronic granulomatous amebic encephalitis. treatment is very difficult and not always effective because of encystation, which makes the amebae highly resistant to anti-amebic drugs. the searc ... | 2014 | 24383326 |
| in vitro efficacy of corifungin against acanthamoeba castellanii trophozoites and cysts. | painful blinding keratitis and fatal granulomatous amebic encephalitis are caused by the free-living amebae acanthamoeba spp. several prescription eye medications are used to treat acanthamoeba keratitis, but the infection can be difficult to control because of recurrence of infection. for the treatment of encephalitis, no single drug was found useful, and in spite of the use of a combination of multiple drugs, the mortality rate remains high. therefore, efficient, novel drugs are urgently neede ... | 2014 | 24366747 |
| in vitro adhesion of acanthamoeba castellanii to soft contact lenses depends on water content and disinfection procedure. | to compare the potential of different soft contact lenses to be contaminated with acanthamoeba castellanii as a function of material parameters and cleaning procedures. | 2014 | 24361096 |
| identification of atg8 isoform in encysting acanthamoeba. | autophagy-related protein 8 (atg8) is an essential component of autophagy formation and encystment of cyst-forming parasites, and some protozoa, such as, acanthamoeba, entamoeba, and dictyostelium, have been reported to possess a type of atg8. in this study, an isoform of atg8 was identified and characterized in acanthamoeba castellanii (acatg8b). acatg8b protein was found to encode 132 amino acids and to be longer than acatg8 protein, which encoded 117 amino acids. real-time pcr analysis showed ... | 2013 | 24327773 |
| role of pathogens in multiple sclerosis. | multiple sclerosis (ms) is an inflammatory demyelinating autoimmune disease of the central nervous system (cns). although the etiology of ms is unknown, genetic and environmental factors play a role. infectious pathogens are the likely environmental factors involved in the development of ms. pathogens associated with the development or exacerbation of ms include bacteria, such as mycoplasma pneumoniae and chlamydia pneumoniae, the staphylococcus aureus-produced enterotoxins that function as supe ... | 2017 | 24266364 |
| interaction of aspergillus fumigatus conidia with acanthamoeba castellanii parallels macrophage-fungus interactions. | aspergillus fumigatus and free-living amoebae are common inhabitants of soil. mechanisms of a. fumigatus to circumvent the amoeba's digestion may facilitate overcoming the vertebrate macrophage defence mechanisms. we performed co-culture experiments using a. fumigatus conidia and the amoeba acanthamoeba castellanii. approximately 25% of the amoebae ingested a. fumigatus conidia after 1 h of contact. during intra-amoebal passage, part of the ingested conidia was able to escape the food vacuole an ... | 2013 | 24249290 |
| the cyclic amp phosphodiesterase rega critically regulates encystation in social and pathogenic amoebas. | amoebas survive environmental stress by differentiating into encapsulated cysts. as cysts, pathogenic amoebas resist antibiotics, which particularly counteracts treatment of vision-destroying acanthamoeba keratitis. limited genetic tractability of amoeba pathogens has left their encystation mechanisms unexplored. the social amoeba dictyostelium discoideum forms spores in multicellular fruiting bodies to survive starvation, while other dictyostelids, such as polysphondylium pallidum can additiona ... | 2014 | 24184654 |
| codon usage, amino acid usage, transfer rna and amino-acyl-trna synthetases in mimiviruses. | mimiviruses are giant viruses that infect phagocytic protists, including acanthamoebae spp., which were discovered during the past decade. they are the current record holder among viruses for their large particle and genome sizes. one group is composed of three lineages, referred to as a, b and c, which include the vast majority of the mimiviridae members. cafeteria roenbergensis virus represents a second group, though the mimiviridae family is still expanding. we analyzed the codon and amino ac ... | 2013 | 24157883 |
| evidence for a hydrogenosomal-type anaerobic atp generation pathway in acanthamoeba castellanii. | diverse, distantly-related eukaryotic lineages have adapted to low-oxygen environments, and possess mitochondrion-related organelles that have lost the capacity to generate adenosine triphosphate (atp) through oxidative phosphorylation. a subset of these organelles, hydrogenosomes, has acquired a set of characteristic atp generation enzymes commonly found in anaerobic bacteria. the recipient of these enzymes could not have survived prior to their acquisition had it not still possessed the electr ... | 2013 | 24086244 |
| vbnc legionella pneumophila cells are still able to produce virulence proteins. | legionella pneumophila is the agent responsible for legionellosis. numerous bacteria, including l. pneumophila, can enter into a viable but not culturable (vbnc) state under unfavorable environmental conditions. in this state, cells are unable to form colonies on standard medium but are still alive. here we show that vbnc l. pneumophila cells, obtained by monochloramine treatment, were still able to synthesize proteins, some of which are involved in virulence. protein synthesis was measured usin ... | 2013 | 24064547 |
| in vitro comparative assessment of different viability assays in acanthamoeba castellanii and acanthamoeba polyphaga trophozoites. | the species of the genus acanthamoeba are opportunistic protozoan parasites that cause different diseases in humans, such as amoebic keratitis and granulomatous encephalitis. the rise in the rate of acanthamoeba keratitis, mainly due to the increase in contact lens wearers, turns the development of viability assays using a multi-well plate reader as a tool for screening new antiamoebic agents in vitro into an important goal. in our study, the viability assays prestoblue®, resazurin sodium salt, ... | 2013 | 24026387 |
| the trojan horse of the microbiological arms race: phage-encoded toxins as a defence against eukaryotic predators. | phage-encoded shiga toxin (stx) acts as a bacterial defence against the eukaryotic predator tetrahymena. to function as an effective bacterial anti-predator defence, stx must kill a broad spectrum of predators. consistent with that assertion, we show here that bacterially encoded stx efficiently kills the bacteriovore acanthamoeba castellanii in co-culture. we also show that, in addition to stx, the phage-encoded exotoxin, diphtheria toxin (dtx) expressed by corynebacterium diphtheriae also can ... | 2014 | 23981100 |
| stationary phase and mature infectious forms of legionella pneumophila produce distinct viable but non-culturable cells. | legionella pneumophila is an intracellular bacterial parasite of freshwater protozoa and an accidental waterborne human pathogen. l. pneumophila is highly pleomorphic showing several forms that differentiate within its developmental cycle. in water, l. pneumophila produces viable but non-culturable cells (vbnccs), which remain largely uncharacterized. we produced vbnccs from two developmental forms of l. pneumophila [stationary phase forms (spfs) and mature infectious forms (mifs)] in two water ... | 2014 | 23968544 |
| from amoeba to macrophages: exploring the molecular mechanisms of legionella pneumophila infection in both hosts. | legionella pneumophila is a gram-negative bacterium and the causative agent of legionnaires' disease. it replicates within amoeba and infects accidentally human macrophages. several similarities are seen in the l. pneumophila-infection cycle in both hosts, suggesting that the tools necessary for macrophage infection may have evolved during co-evolution of l. pneumophila and amoeba. the establishment of the legionella-containing vacuole (lcv) within the host cytoplasm requires the remodeling of t ... | 2013 | 23949285 |
| density of environmental acanthamoeba and their responses to superheating disinfection. | exposure to viable acanthamoeba may cause fatal encephalitis and blinding keratitis in humans. quantification of environmental acanthamoeba by a reliable analytical assay is essential to assess the risk of human exposure and efficacy of control measures (e.g., superheating). two dna binding dyes (ethidium monoazide (ema) and propidium monoazide) coupled with real-time quantitative pcr (qpcr) were tested for the ability in selectively quantifying viable acanthamoeba castellanii. this newly develo ... | 2013 | 23933810 |
| antimicrobial action of biguanides on the viability of acanthamoeba cysts and assessment of cell toxicity. | to assess dose- and concentration-dependent rates of biguanides on the viability of acanthamoeba cysts isolated from severe ulcerative keratitis, and to correlate cysticidal activites with cytotoxic profiles in corneal and endothelial cells. | 2013 | 23900604 |
| kinetic characterization of the atpase and actin-activated atpase activities of acanthamoeba castellanii myosin-2. | phosphorylation of ser-639 in loop-2 of the catalytic motor domain of the heavy chain of acanthamoeba castellanii myosin-2 and the phosphomimetic mutation s639d have been shown previously to down-regulate the actin-activated atpase activity of both the full-length myosin and single-headed subfragment-1 (liu, x., lee, d. y., cai, s., yu, s., shu, s., levine, r. l., and korn, e. d. (2013) proc. natl. acad. sci. u.s.a. 110, e23-e32). in the present study we determined the kinetic constants for each ... | 2013 | 23897814 |
| heavy metal tolerance genes alter cellular thermodynamics in pseudomonas putida and river pseudomonas spp. and influence amebal predation. | predation rates were measured for two acanthamoeba castellanii strains feeding on metal-tolerant and metal-sensitive strains of pseudomonas putida and compared with cellular thermodynamic data. predation rates by a. castellanii strain atcc 30010 correlated with cell volume of the prey. to explore whether this observation could be environmentally relevant, pseudomonad species were isolated from a pristine and a metal-contaminated river and were paired based on phylogenetic and physiological relat ... | 2013 | 23895438 |
| early expression of the type iii secretion system of parachlamydia acanthamoebae during a replicative cycle within its natural host cell acanthamoeba castellanii. | the type three secretion system (t3ss) operons of chlamydiales bacteria are distributed in different clusters along their chromosomes and are conserved at both the level of sequence and genetic organization. a complete characterization of the temporal expression of multiple t3ss components at the transcriptional and protein levels has been performed in parachlamydia acanthamoebae, replicating in its natural host cell acanthamoeba castellanii. the t3ss components were classified in four different ... | 2013 | 23861207 |
| the ancient and widespread nature of the er-mitochondria encounter structure. | mitochondria are the result of a billion years of integrative evolution, converting a once free-living bacterium to an organelle deeply linked to diverse cellular processes. one way in which mitochondria are integrated with nonendosymbiotically derived organelles is via endoplasmic reticulum (er)-mitochondria contact sites. the er membrane is physically tethered to the mitochondrial outer membrane by the er-mitochondria encounter structure (ermes). however, to date, ermes has only ever been foun ... | 2013 | 23813918 |
| role of phospholipase a₂ (pla₂) inhibitors in attenuating apoptosis of the corneal epithelial cells and mitigation of acanthamoeba keratitis. | the aim of this study is to determine if the mannose-induced protein (mip-133) from acanthamoeba castellanii trophozoites induces apoptosis of corneal epithelial cells through a cytosolic phospholipase a2α (cpla2α)-mediated pathway. the efficacy of cpla2α inhibitors to provide protection against acanthamoeba keratitis was examined in vivo. chinese hamster corneal epithelial (hcorn) cells were incubated with or without mip-133. mip-133 induces significant increase in cpla2α and macrophage inflamm ... | 2013 | 23792108 |
| the effect of different environmental conditions on the encystation of acanthamoeba castellanii belonging to the t4 genotype. | in this study, acanthamoeba castellanii was cultivated under different stress conditions to induce possible encystation. the morphological and histological properties were analysed by light and electron microscopy as well as cyst-specific staining. the findings revealed that cysts prepared through liquid medium using higher osmolarity as a trigger (10% glucose with 50mm magnesium chloride for 72 h) are similar to cysts prepared using non-nutrient agar (nutrient deprivation as a trigger in platin ... | 2013 | 23769934 |
| amoebicidal activity of phytosynthesized silver nanoparticles and their in vitro cytotoxicity to human cells. | acanthamoeba causes infections in humans and other animals and it is important to develop treatment therapies. jatropha curcas, jatropha gossypifolia and euphorbia milii plant extracts synthesized stable silver nanoparticles (agnps) that were relatively stable. amoebicidal activity of j. gossypifolia, j. curcas and e. milii leaf extracts showed little effect on viability of acanthamoeba castellanii trophozoites. plant-synthesized agnps showed higher amoebicidal activity. agnps synthesized by j. ... | 2013 | 23746354 |
| acanthamoeba migration in an electric field. | we investigated the in vitro response of acanthamoeba trophozoites to electric fields (efs). | 2013 | 23716626 |
| activity assessment of tunisian olive leaf extracts against the trophozoite stage of acanthamoeba. | the olive tree (olea europaea, oleaceae) has historically provided huge economic and nutritional benefits to the mediterranean basin. in fact, olive leaf extracts have also been used by native people of this area in folk medicine to treat fever and other diseases such as malaria. recently, several studies have focused on the extraction of high-added-value compounds from olive leaves. however, no previous studies have been developed in order to evaluate the activity of these extracts against acan ... | 2013 | 23681194 |
| in vitro efficacies of clinically available drugs against growth and viability of an acanthamoeba castellanii keratitis isolate belonging to the t4 genotype. | the effects of clinically available drugs targeting muscarinic cholinergic, adrenergic, dopaminergic, and serotonergic receptors; intracellular calcium levels and/or the function of calcium-dependent biochemical pathways; ion channels; and cellular pumps were tested against a keratitis isolate of acanthamoeba castellanii belonging to the t4 genotype. in vitro growth inhibition (amoebistatic) assays were performed by incubating a. castellanii with various concentrations of drugs in the growth med ... | 2013 | 23669391 |
| acanthamoeba genotype t4 detected in naturally-infected feline corneas found to be in homology with those causing human keratitis. | a total of 10 out of 65 cornea swab samples from cats with eye symptoms showed acanthamoeba-like morphology after cultivation. by pcr and dna sequencing of acanthamoeba diagnostic fragment 3 (df3), all 10 isolates from the positive samples were categorized into two homologous groups of afc1 (pm1, pm2, pm3, pf6, km7, kf8, kmk9) and afc2 (pm4, pm5, kfk10) due to the presence of bases a(354) and g(354), respectively. furthermore, df3 of afc1 and afc2 showed 100% similarity with genbank reference is ... | 2013 | 23665719 |
| new long chain bases in lipophosphonoglycan of acanthamoeba castellanii. | the polymer called lipophosphonoglycan (lpg) was isolated from acanthamoeba castellanii membranes after exhaustive delipidation and butanol extraction. a novel extremely long phytosphingosine was revealed in glycoinositolphosphosphingolipid (gipsl). all data obtained by gas-liquid chromatography coupled with ms analyses of products liberated during acid methanolysis and products of sodium metaperiodate and permanganate-periodate oxidations showed an unusual pattern of long chain bases (lcb) with ... | 2013 | 23636605 |
| fungal virulence in a lepidopteran model is an emergent property with deterministic features. | abstract virulence has been proposed to be an emergent property, which by definition implies that it is not reducible to its components, but this application of a philosophical concept to the host-microbe interaction has not been experimentally tested. the goals of our study were to analyze the correlation of the phenotype with the ability to cause disease and to determine the dynamics of an experimental cryptococcal infection in galleria mellonella and acanthamoeba castellanii. by studying the ... | 2013 | 23631914 |
| effects of multipurpose solutions on the viability and encystment of acanthamoeba determined by flow cytometry. | to evaluate simultaneously the effects of multipurpose contact lens care solution (mps) on the viability and encystment of acanthamoeba using flow cytometry. | 2013 | 23584044 |
| shiga toxins decrease enterohaemorrhagic escherichia coli survival within acanthamoeba castellanii. | enterohaemorrhagic escherichia coli (ehec) are zoonotic pathogens transmitted to humans through contaminated water or bovine products. one of the strategies used by pathogenic bacteria to survive in aquatic environments is using free-living amoebae as hosts. acanthamoeba castellanii is an amoeba known to host several waterborne pathogens. this study investigates the survival of ehec with a. castellanii, which could contribute to its spread and transmission to humans. we used a gentamicin protect ... | 2013 | 23581502 |
| horizontal transfer and evolution of prokaryote transposable elements in eukaryotes. | horizontal transfer (ht) of transposable elements (tes) plays a key role in prokaryotic evolution, and mounting evidence suggests that it has also had an important impact on eukaryotic evolution. although many prokaryote-to-prokaryote and eukaryote-to-eukaryote hts of tes have been characterized, only few cases have been reported between prokaryotes and eukaryotes. here, we carried out a comprehensive search for all major groups of prokaryotic insertion sequences (iss) in 430 eukaryote genomes. ... | 2013 | 23563966 |
| the transcriptional response of cryptococcus neoformans to ingestion by acanthamoeba castellanii and macrophages provides insights into the evolutionary adaptation to the mammalian host. | virulence of cryptococcus neoformans for mammals, and in particular its intracellular style, was proposed to emerge from evolutionary pressures on its natural environment by protozoan predation, which promoted the selection of strategies that allow intracellular survival in macrophages. in fact, acanthamoeba castellanii ingests yeast cells, which then can replicate intracellularly. in addition, most fungal factors needed to establish infection in the mammalian host are also important for surviva ... | 2013 | 23524994 |
| environmental amoebae do not support the long-term survival of virulent mycobacteria. | to test the hypothesis that mycobacterium bovis can persist in the environment within protozoa. | 2013 | 23398391 |
| hydroxynonenal-stimulated activity of the uncoupling protein in acanthamoeba castellanii mitochondria under phosphorylating conditions. | the influence of 4-hydroxy-2-nonenal (hne), a lipid peroxidation end product, on the activity of the amoeba acanthamoeba castellanii uncoupling protein (acucp) in isolated phosphorylating mitochondria was studied. under phosphorylating conditions, exogenously added hne induced gtp-sensitive acucp-mediated mitochondrial uncoupling. the hne-induced proton leak decreased the yield of oxidative phosphorylation in an hne concentration-dependent manner. the present study describes how the contribution ... | 2013 | 23362201 |
| protamine as a potential amoebicidal agent for contact lens disinfection. | to evaluate the amoebicidal efficacy of protamine with polyhexamethylene biguanide (phmb) and ethylenediamine tetraacetic acid (edta). | 2013 | 23334310 |
| effects of harmful cyanobacteria on the freshwater pathogenic free-living amoeba acanthamoeba castellanii. | grazing is a major regulating factor in cyanobacterial population dynamics and, subsequently, considerable effort has been spent on investigating the effects of cyanotoxins on major metazoan grazers. however, protozoan grazers such as free-living amoebae can also feed efficiently on cyanobacteria, while simultaneously posing a major threat for public health as parasites of humans and potential reservoirs of opportunistic pathogens. in this study, we conducted several experiments in which the fre ... | 2013 | 23333903 |
| acanthamoeba castellanii cysts: new ultrastructural findings. | during acanthamoeba castellanii trophozoite-cysts differentiation, four morphological stages were identified by scanning electron microscopy: trophozoite, precyst, immature cysts, and mature cysts. fluorescence microscopy reveals the presence of small cumulus of actin in the cytoplasm of precysts after treatment with rhodamine phalloidin. by the contrary, in mature cysts, fluorescence was not observed. however, when excystation was induced, large fluorescent patches were present. by transmission ... | 2013 | 23319266 |
| evaluation of inhibitory potential of some selective methanolic plants extracts on biological characteristics of acanthamoeba castellanii using human corneal epithelial cells in vitro. | acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. this is due to limited availability of effective anti-acanthamoeba drugs. the objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological p ... | 2013 | 23306385 |
| silencing of xylose isomerase and cellulose synthase by sirna inhibits encystation in acanthamoeba castellanii. | a key challenge in the successful treatment of acanthamoeba infections is its ability to transform into a dormant cyst form that is resistant to physiological conditions and pharmacological therapies, resulting in recurrent infections. the carbohydrate linkage analysis of cyst walls of acanthamoeba castellanii showed variously linked sugar residues, including xylofuranose/xylopyranose, glucopyranose, mannopyranose, and galactopyranose. here, it is shown that exogenous xylose significantly reduce ... | 2013 | 23271570 |
| in vitro evaluation of the effectiveness of new water-stable cationic carbosilane dendrimers against acanthamoeba castellanii uah-t17c3 trophozoites. | acanthamoeba is one of the most common free-living amoebas which is widespread in the environment and can infect humans, causing diseases such as keratitis and encephalitis. in this paper we examine for the first time the amebicidal activity of the family of cationic dendrimers ng-[si{(ch(2))(3)n(+)(me)(et)(ch(2))(2)nme(3) (+)}2i(-)]( x ) (where n denotes the generations: zero (n = 0, x = 1), first (n = 1, x = 4), and second (n = 2, x = 8); for simplicity, they were named as 0g-cnn2, 1g-cnn8, an ... | 2013 | 23263327 |
| absence of a universal element for trnahis identity in acanthamoeba castellanii. | the additional g(-1) nucleotide on trna(his) is a nearly universal feature that specifies trna(his) identity in all three domains of life. in eukaryotes, the g(-1) identity element is obtained by a post-transcriptional pathway, through the unusual 3'-5' polymerase activity of the highly conserved trna(his) guanylyltransferase (thg1) enzyme, and no examples of eukaryotic histidyl-trnas that lack this essential element have been identified. here we report that the eukaryote acanthamoeba castellani ... | 2013 | 23241387 |
| effects of mannose on pathogenesis of acanthamoeba castellanii. | acanthamoeba spp. are single-celled protozoan organisms that are widely distributed in the environment. in this study, to understand functional roles of a mannose-binding protein (mbp), acanthamoeba castellanii was treated with methyl-alpha-d-mannopyranoside (mannose), and adhesion and cytotoxicity of the amoeba were analyzed. in addition, to understand the association of mbp for amoeba phagocytosis, phagocytosis assay was analyzed using non-pathogenic bacterium, escherichia coli k12. amoebae tr ... | 2012 | 23230338 |
| short-cut pathway to synthesize cellulose of encysting acanthamoeba. | the mature cyst of acanthamoeba is highly resistant to various antibiotics and therapeutic agents. cyst wall of acanthamoeba are composed of cellulose, acid-resistant proteins, lipids, and unidentified materials. because cellulose is one of the primary components of the inner cyst wall, cellulose synthesis is essential to the process of cyst formation in acanthamoeba. in this study, we hypothesized the key and short-step process in synthesis of cellulose from glycogen in encysting acanthamoeba c ... | 2012 | 23230337 |
| broad spectrum antimicrobial activity of melimine covalently bound to contact lenses. | to develop a stable antimicrobial contact lens, which is effective against the international organization for standardization (iso) panel microorganisms, acanthamoeba castellanii and drug resistant strains of pseudomonas aeruginosa and staphylococcus aureus. | 2013 | 23211820 |
| preliminary crystallographic analysis of the megavirus superoxide dismutase. | megavirus chilensis, a close relative of the mimivirus giant virus, is able to replicate in acanthamoeba castellanii. the first step of viral infection involves the internalization of the virions in host vacuoles. it has been experimentally demonstrated that mimivirus particles contain many proteins capable of resisting oxidative stress, as encountered in the phagocytic process. these proteins are conserved in megavirus, which has an additional gene (mg277) encoding a putative superoxide dismuta ... | 2012 | 23192047 |
| "marseilleviridae", a new family of giant viruses infecting amoebae. | the family "marseilleviridae" is a new proposed taxon for giant viruses that infect amoebae. its first member, acanthamoeba polyphaga marseillevirus (apmav), was isolated in 2007 by culturing on amoebae a water sample collected from a cooling tower in paris, france. apmav has an icosahedral shape with a diameter of ≈250 nm. its genome is a double-stranded circular dna that is 368,454 base pairs (bp) in length. the genome has a gc content of 44.7 % and is predicted to encode 457 proteins. phyloge ... | 2013 | 23188494 |