Comparative Genome-Scale Metabolic Modeling of Metallo-Beta-Lactamase –Producing Multidrug-Resistant Klebsiella pneumoniae Clinical Isolates
The emergence and spread of metallo-beta-lactamase–producing multidrug-resistant Klebsiella pneumoniae is a serious public health threat, which is further complicated by the increased prevalence of colistin resistance. The link between antimicrobial resistance acquired by strains of Klebsiella and their unique metabolic capabilities has not been determined. Here, we reconstruct genome-scale metabolic models for 22 K. pneumoniae strains with various resistances to different antibiotics including two strains exhibiting colistin resistance isolated from Cairo, Egypt. We use the models to predict growth capabilities on 2...
Source: Frontiers in cellular and infection microbiology - May 24, 2019 Category: Microbiology Source Type: research

Determinants of Coinfection in the Mycoviruses
(Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 24, 2019 Category: Microbiology Source Type: research

MnmE, a Central tRNA-Modifying GTPase, Is Essential for the Growth, Pathogenicity, and Arginine Metabolism of Streptococcus suis Serotype 2
In this study, a guanosine triphosphatase (GTPase) MnmE homologue was identified in a Chinese isolate (SC19) that drives a tRNA modification reaction. A mnmE deletion strain (ΔmnmE) and a complementation strain (CΔmnmE) were constructed to systematically decode the characteristics and functions of MnmE both in vitro and in vivo studies via proteomic analysis. Phenotypic analysis revealed that the ΔmnmE strain displayed deficient growth, attenuated pathogenicity, and perturbation of the arginine metabolic pathway mediated by the arginine deiminase system (ADS). Consistently, tandem mass tag -based quantita...
Source: Frontiers in cellular and infection microbiology - May 24, 2019 Category: Microbiology Source Type: research

Comparative Genome Analysis of Uropathogenic Morganella morganii Strains
This study was aimed at sequencing and comparing the genomes of three M. morganii strains isolated from the urine samples of patients with community-acquired urinary tract infections. Draft genome sequencing was conducted using the Illumina HiSeq platform. The genomes of MM 1, MM 4, and MM 190 strains have a size of 3.82-3.97 Mb and a GC content of 50.9-51%. Protein-coding sequences (CDS) represent 96.1% of the genomes, RNAs are encoded by 2.7% of genes and pseudogenes account for 1.2% of the genomes. The pan-genome containes 4,038 CDS, of which 3,279 represent core genes. 6-10 prophages and 21-33 genomic islands were iden...
Source: Frontiers in cellular and infection microbiology - May 22, 2019 Category: Microbiology Source Type: research

Prevalence of Panton-Valentine Leukocidin (PVL) and Antimicrobial Resistance in Community-Acquired Clinical Staphylococcus aureus in an Urban Gambian Hospital: A 11-Year Period Retrospective Pilot Study
Conclusion: PVL expression is high among clinical S. aureus strains among Gambian patients. Reporting of PVL-SA clinical infections is necessary to enable the monitoring of the clinical impact of these strains in the population and guide prevention of the spread of virulent PVL-positive CA-MRSA strains. (Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 22, 2019 Category: Microbiology Source Type: research

Aspergillus fumigatus Challenged by Human Dendritic Cells: Metabolic and Regulatory Pathway Responses Testify a Tight Battle
In conclusion, we provide an integrated picture of the metabolic and regulatory aspects of the interaction of A. fumigatus and dendritic cells during infection. (Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 22, 2019 Category: Microbiology Source Type: research

Structural Determinants of the APOBEC3G N-Terminal Domain for HIV-1 RNA Association
APOBEC3G (A3G) is a cellular protein that inhibits HIV-1 infection through virion incorporation. The interaction of the A3G N-terminal domain (NTD) with RNA is essential for A3G incorporation in the HIV-1 virion. The interaction between A3G-NTD and RNA is not completely understood. The A3G-NTD is also recognized by HIV-1 Viral infectivity factor (Vif) and A3G-Vif binding leads to A3G degradation. Therefore, the A3G-Vif interaction represents a novel target for the development of antiviral therapies that block HIV replication. However, targeting the A3G-Vif interactions could disrupt the A3G-RNA interactions that are requir...
Source: Frontiers in cellular and infection microbiology - May 21, 2019 Category: Microbiology Source Type: research

Alterations to the Lung Microbiome in Idiopathic Pulmonary Fibrosis Patients
In this study, 17 IPF patients and 38 healthy subjects (smokers and non-smokers) were recruited. For the PCA, the first and the second principal component explained 16.3% and 13.4% of the overall variability, respectively. The β diversity of microbiome was reduced in the IPF group. Signature of IPF’s microbes was enriched of Streptococcus, Pseudobutyrivibrio, and Anaerorhabdus. The translocation of lung microbiome was shown that 32.84% of them were from oral. After analysis of gene function, ABC transporter systems, biofilm formation, and two-component regulatory system were enriched in IPF patients’ micro...
Source: Frontiers in cellular and infection microbiology - May 21, 2019 Category: Microbiology Source Type: research

Commentary: Dysregulated Microbial Fermentation of Soluble Fiber Induces Cholestatic Liver Cancer
(Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 21, 2019 Category: Microbiology Source Type: research

Development of a Novel ex vivo Nasal Epithelial Cell Model Supporting Colonization With Human Nasal Microbiota
The nasal mucosa provides first line defense against inhaled pathogens while creating a unique microenvironment for bacterial communities. Studying the impact of microbiota in the nasal cavity has been difficult due to limitations with current models including explant cultures, primary cells, or neoplastic cell lines. Most notably, none have been shown to support reproducible colonization by bacterial communities from human donors. Therefore, to conduct controlled studies of the human nasal ecosystem, we have developed a novel ex vivo mucosal model that supports bacterial colonization of a cultured host mucosa created by i...
Source: Frontiers in cellular and infection microbiology - May 21, 2019 Category: Microbiology Source Type: research

Establishment and Characterization of an Immortalized Porcine Oral Mucosal Epithelial Cell Line as a Cytopathogenic Model for Porcine Circovirus 2 Infection
Porcine circovirus 2 (PCV2) is a major etiological agent for porcine circovirus-associated diseases and causes enormous economic losses in domestic and overseas swine production. However, there are currently no suitable cell models to study the cytopathic effects of PCV2 in vitro, which severely restricts the study of PCV2 pathogenesis. In the present study, we established an immortalized porcine oral mucosal epithelial cell line (hTERT-POMEC) by introducing the hTERT gene into primary porcine oral mucosal epithelial cells (POMECs) derived from a neonatal, unsuckled piglet. The hTERT-POMEC cells have a homogeneous cobblest...
Source: Frontiers in cellular and infection microbiology - May 21, 2019 Category: Microbiology Source Type: research

Glutathione Activates Type III Secretion System Through Vfr in Pseudomonas aeruginosa
In this study, a comprehensive transcriptome analysis of the ΔgshAΔgshB mutant lacking the ability to synthesize glutathione (GSH) in P. aeruginosa was used to elucidate the role of glutathione in the pathogenesis of P. aeruginosa. The transcriptome result shows that the expression of some secretion systems and regulatory genes were impaired, including type III secretion system (T3SS) and type VI secretion system (T6SS). ΔgshAΔgshB caused a reduction in virulence in a mouse model of acute pneumonia, and also showed weakened swimming and swarming motilities and decreased biofilm formation. These resu...
Source: Frontiers in cellular and infection microbiology - May 16, 2019 Category: Microbiology Source Type: research

Aloe-emodin Attenuates Staphylococcus aureus Pathogenicity by Interfering With the Oligomerization of α-Toxin
In this study, we found that aloe-emodin (AE), a natural compound lacking anti-S. aureus activity, could inhibit the hemolytic activity of α-toxin. Oligomerization assays, molecular dynamics simulations and fluorescence-quenching analyses were used to determine the mechanism of this inhibition. The oligomerization of α-toxin was restricted by the engagement of AE with K110, T112 and M113 of the toxin, which eventually resulted in inhibition of the hemolytic activity. Lactate dehydrogenase and live/dead assays demonstrated that AE decreased the injury of human lung epithelial cells (A549) and mouse lung macropha...
Source: Frontiers in cellular and infection microbiology - May 15, 2019 Category: Microbiology Source Type: research

Suppression of Alternative Lipooligosaccharide Glycosyltransferase Activity by UDP-Galactose Epimerase Enhances Murine Lung Infection and Evasion of Serum IgM
In pathogens that produce lipooligosaccharide (LOS), sugar residues within the surface-exposed LOS outer core mediate interactions with components of the host immune system, promoting bacterial infection. Many LOS structures are controlled by phase variation mediated by random slipped-strand base mispairing, which can reversibly switch gene expression on or off. Phase variation diversifies the LOS, however its adaptive role is not well-understood. Nontypeable Haemophilus influenzae (NTHi) is an important pathogen that causes a range of illnesses in the upper and lower respiratory tract. In NTHi a phase variable galactosylt...
Source: Frontiers in cellular and infection microbiology - May 15, 2019 Category: Microbiology Source Type: research

Molecular Characterization of a Chrysovirus Isolated From the Citrus Pathogen Penicillium crustosum and Related Fungicide Resistance Analysis
Penicillium sp. are damaging to a range of foods and fruits including citrus. To date, double-stranded (ds)RNA viruses have been reported in most Penicillium species but not in citrus pathogen P. crustosum. Here we report a novel dsRNA virus, designated as Penicillium crustosum chrysovirus 1 (PcCV1) and isolated from P. crustosum strain HS-CQ15. PcCV1 genome comprises four dsRNA segments, referred to as dsRNA1, dsRNA2, dsRNA3 and dsRNA4, which are 3600, 3177, 3078, and 2808 bp in length, respectively. Sequence analysis revealed the presence of four open reading frames (ORFs) in the PcCV1 genome. ORF1 in dsRNA1 encodes a pu...
Source: Frontiers in cellular and infection microbiology - May 15, 2019 Category: Microbiology Source Type: research

Corrigendum: Monocyte-Derived Dendritic Cells as Model to Evaluate Species Tropism of Mosquito-Borne Flaviviruses
(Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 15, 2019 Category: Microbiology Source Type: research

Active Surveillance of Carbapenemase-Producing Organisms (CPO) Colonization With Xpert Carba-R Assay Plus Positive Patient Isolation Proves to Be Effective in CPO Containment
Background: Rapid screening of patients for colonization with carbapenemase-producing organisms (CPO), coupled with implementation of infection prevention strategies, has the potential to contain the spread of CPO. Methods: We first evaluated the performance of Xpert Carba-R assay (in comparison with other phenotypic methods) for carbapenemase detection using clinical isolates, and then used it to determine the intestinal CPO colonization in hospitalized patients. We then assessed the effectiveness of patient isolation in controlling the spread of CPO in a medical intensive care unit. Results: The Xpert Carba-R assay re...
Source: Frontiers in cellular and infection microbiology - May 14, 2019 Category: Microbiology Source Type: research

Impact of Toxoplasma gondii Infection on Host Non-coding RNA Responses
As an intracellular microbe, Toxoplasma gondii must establish a highly intimate relationship with its host to ensure success as a parasite. Many studies over the last decade-and-a-half have highlighted how the host reshapes its immunoproteome to survive infection, and conversely how the parasite regulates host responses to ensure persistence. The role of host non-protein-coding RNA during infection is a vast and largely unexplored area of emerging interest. The potential importance of this facet of the host-parasite interaction is underscored by current estimates that as much as 80% of the host genome is transcribed into n...
Source: Frontiers in cellular and infection microbiology - May 14, 2019 Category: Microbiology Source Type: research

Evaluation of Sodium Hypochlorite Irrigant, Bingpeng Irrigant, and Fufang Bingpeng Irrigant as Endodontic Irrigants During Passive Ultrasonic Irrigation
The increased antibiotic resistant strains and side effects caused by synthetic drugs make it is a necessary to look for herbal alternatives. In the present study, the antimicrobial test, cell cytotoxicity test, cleaning test, q-PCR and high-throughput sequencing analyses were used to evaluate the potential of Fufang Bingpeng irrigant as root canal irrigant. Our in vitro results indicated that Fufang Bingpeng irrigant made a low minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for P. gingivalis ATCC 33277 (6.25% vs. 12.5%), P. intermedius ATCC 25611(6.25% vs. 6.25%), F. nucleatum ATCC 252...
Source: Frontiers in cellular and infection microbiology - May 10, 2019 Category: Microbiology Source Type: research

Nucleoid-Associated Protein HU: A Lilliputian in Gene Regulation of Bacterial Virulence
Histone-like proteins are group of small but abundant proteins in bacterial cells. These transcription regulators are responsible for many important cellular processes and are involved in pathogenesis of bacteria as well. The best known histone-like proteins, such as HU, FIS, H-NS and IHF, are often discussed. The most important findings in the HU protein researches are described in this minireview. Its roles in DNA compaction, shape modulation and negative supercoiling induction have been intensively studied. HU proteins regulate bacteria survival, growth, SOS response, virulence genes expression, cell division and many o...
Source: Frontiers in cellular and infection microbiology - May 10, 2019 Category: Microbiology Source Type: research

ESX Secretion-Associated Protein C From Mycobacterium tuberculosis Induces Macrophage Activation Through the Toll-Like Receptor-4/Mitogen-Activated Protein Kinase Signaling Pathway
M. tuberculosis, as a facultative intracellular pathogen, can interact with host macrophages and modulate macrophage function to influence innate and adaptive immunity. Proteins secreted by the ESX-1 secretion system are involved in this relationship. Although the importance of ESX-1 in host-pathogen interactions and virulence is well known, the primary role is ascribed to EsxA (EAST-6) in mycobacterial pathogenesis and the functions of individual components in the interactions between pathogens and macrophages are still unclear. Here, we investigated the effects of EspC on macrophage activation. The EspC protein is encode...
Source: Frontiers in cellular and infection microbiology - May 10, 2019 Category: Microbiology Source Type: research

Infection of Human Neutrophils With Leishmania infantum or Leishmania major Strains Triggers Activation and Differential Cytokines Release
Leishmaniases are neglected diseases, caused by intracellular protozoan parasites of the Leishmania (L.) genus. Although the principal host cells of the parasites are macrophages, neutrophils are the first cells rapidly recruited to the site of parasites inoculation, where they play an important role in the early recognition and elimination of the parasites. The nature of early interactions between neutrophils and Leishmania could influence the outcome of infection. Herein we aimed to evaluate whether different Leishmania strains, responsible for distinct clinical manifestations, could influence ex vivo functional activity...
Source: Frontiers in cellular and infection microbiology - May 10, 2019 Category: Microbiology Source Type: research

Modeling Host-Pathogen Interaction to Elucidate the Metabolic Drug Response of Intracellular Mycobacterium tuberculosis
Little is known about the metabolic state of Mycobacterium tuberculosis (Mtb) inside the phagosome, a compartment inside phagocytes for killing pathogens and other foreign substances. We have developed a combined model of Mtb and human metabolism, sMtb-RECON and used this model to predict the metabolic state of Mtb during infection of the host. Amino acids are predicted to be used for energy production as well as biomass formation. Subsequently we assessed the effect of increasing dosages of drugs targeting metabolism on the metabolic state of the pathogen and predict resulting metabolic adaptations and flux rerouting thro...
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

MicroRNA and Nonsense Transcripts as Putative Viral Evasion Mechanisms
Viruses use various evasion strategies to overcome host defenses and aid their replication. We propose that RNA viruses use a passive means to elude host anti-viral responses based on complementarity of the viral genomic and associated transcript sequences that mimic or inhibit microRNAs (miRNAs). By hindering the complementarity between the miRNA seed site and the miRNA recognition element, a virus may alter host gene expression and the global landscape regulated by miRNAs. This theory is supported by computational analysis of several paramyxovirus genomes with sequence motifs that are identical or complementary to host m...
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

The Healthy Human Blood Microbiome: Fact or Fiction?
The blood that flows perpetually through our veins and arteries performs numerous functions essential to our survival. Besides distributing oxygen, this vast circulatory system facilitates nutrient transport, deters infection and dispenses heat throughout our bodies. Since human blood has traditionally been considered to be an entirely sterile environment, comprising only blood-cells, platelets and plasma, the detection of microbes in blood was consistently interpreted as an indication of infection. However, although a contentious concept, evidence for the existence of a healthy human blood-microbiome is steadily accumulat...
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

Cross-Protection Against Four Serotypes of Dengue Virus in Mice Conferred by a Zika DNA Vaccine
In this study, we used a Zika DNA vaccine candidate (pV-ZME) expressing the ZIKV premembrane and envelop proteins to immunize BALB/c mice and evaluated the potential cross-reactive immune responses to DENV1–4. We observed that three doses of the pV-ZME vaccine elicited the production of cross-reactive antibodies, cytokines and CD8+ T cell responses and generated cross-protection against DENV1–4. Our results demonstrate a novel approach for design and development of safe Zika and/or dengue vaccines. (Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

Small RNA AvrA Regulates IscR to Increase the Stress Tolerances in SmpB Deficiency of Aeromonas veronii
This study demonstrates the complexity of gene regulation network mediated by sRNA in system biology, and also reflects the strong adaptability of superbacteria A. veronii in the process of evolution. (Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

The Virulence Polysaccharide of Salmonella Typhi Suppresses Activation of Rho Family GTPases to Limit Inflammatory Responses From Epithelial Cells
Vi capsular polysaccharide (Vi) is a major virulence factor of human typhoid-causing pathogen Salmonella enterica serovar Typhi (S.Typhi). It distinguishes S.Typhi from closely related non-typhoidal Salmonella serovars such as S.Typhimurium which do not normally cause systemic infection in humans. Vi not only forms a capsule around S.Typhi but it is also readily released from this pathogen. We have previously reported that Vi targets prohibitin to inhibit cellular responses activated through immune receptors. Here, we show that engagement of membrane prohibitin with Vi prevents Salmonella-induced activation of small Rho-fa...
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

Ticks and Tularemia: Do We Know What We Don't Know?
Francisella tularensis, the causative agent of the zoonotic disease tularemia, is characterized by high morbidity and mortality rates in over 190 different mammalian species, including humans. Based on its low infectious dose, multiple routes of infection, and ability to induce rapid and lethal disease, F. tularensis has been recognized as a severe public health threat – being designated as a NIH Category A Priority Pathogen and a CDC Tier 1 Select Agent. Despite concerns over its use as a bioweapon, most U.S. tularemia cases are tick-mediated and ticks are believed to be the major environmental reservoir for F. tula...
Source: Frontiers in cellular and infection microbiology - May 8, 2019 Category: Microbiology Source Type: research

Respiratory Syncytial Virus Exacerbates Kidney Damages in IgA Nephropathy Mice via the C5a-C5aR1 Axis Orchestrating Th17 Cell Responses
Respiratory viral infections can directly lead to kidney damage such as IgA nephropathy (IgAN), partly due to mucosal immune system dysfunction. Although the activated C5a-C5aR1 axis results in increased Th1 and Th17 frequencies but reduced Treg frequencies in Respiratory syncytial virus (RSV) infection, how this axis affects Th cell disorders in RSV-induced IgAN exacerbation remains unknown. Here, we used a mouse model to dissect the activation of C5a-C5aR1 by RSV and the consequences on the regulation of Th1, Th17 and Treg immune responses in IgA nephropathy. RSV fusion protein was clearly deposited not only in the pulmo...
Source: Frontiers in cellular and infection microbiology - May 7, 2019 Category: Microbiology Source Type: research

TLR4 Participates in the Inflammatory Response Induced by the AAF/II Fimbriae From Enteroaggregative Escherichia coli on Intestinal Epithelial Cells
Enteroaggregative Escherichia coli (EAEC) infections are one of the most frequent causes of persistent diarrhea in children, immunocompromised patients and travelers worldwide. The most prominent colonization factors of EAEC are aggregative adherence fimbriae (AAF). EAEC prototypical strain 042 harbors the AAF/II fimbriae variant, which mediates adhesion to intestinal epithelial cells and participates in the induction of an inflammatory response against this pathogen. However, the mechanism and the cell receptors implicated in eliciting this response have not been fully characterized. Since previous reports have shown that...
Source: Frontiers in cellular and infection microbiology - May 6, 2019 Category: Microbiology Source Type: research

Immunomodulation From Moderate Exercise Promotes Control of Experimental Cutaneous Leishmaniasis
ABSTRACT Physical exercise has been described as an important tool in the prevention and treatment of numerous diseases as it promotes a range of responses and adaptations in several biological systems, including the immune system. Studies on the effect of exercise on the immune system could play a critical role in improving public health. Current literature suggests that moderate intensity exercise can modulate the Th1/Th2 dichotomy directing the immune system to a Th1 cellular immune response, which favors the resolution of infections caused by intracellular microorganisms. Leishmaniasis is a group of diseases presenting...
Source: Frontiers in cellular and infection microbiology - May 3, 2019 Category: Microbiology Source Type: research

Modeling Streptococcus pyogenes Pharyngeal Colonization in the Mouse
In conclusion, the mouse pharyngeal colonization model is an affordable and accessible experimental system that allows a broader group of research groups to test the importance of their findings in an in vivo model. There is a great deal of overlap between the bacterial and immune factors found to be important in human and murine pharyngeal colonization. Although MHC-II humanized mice could prove useful in answering certain questions, the use of inbred mouse lines appears to be sufficient for evaluation of most questions, both related to bacterial factors and the host immune response. However, when promising treatments or ...
Source: Frontiers in cellular and infection microbiology - May 2, 2019 Category: Microbiology Source Type: research

Leishmania braziliensis Infection Enhances Toll-Like Receptors 2 and 4 Expression and Triggers TNF- α and IL-10 Production in Human Cutaneous Leishmaniasis
This study was carried out in accordance with the recommendations of Institutional Review Board of the Federal University of Bahia, Brazil, with written informed consent from all subjects. All subjects gave written informed consent in accordance with the Declaration of Helsinki. The protocol was approved by the Institutional Review Board of the Federal University of Bahia, Brazil (approval number 693.111). Human Blood Samples and Preparation of Peripheral Blood Cells Peripheral blood mononuclear cells (PBMC) were separated from heparinized venous blood by Ficoll-Hypaque gradient centrifugation. Cells were then washed in ...
Source: Frontiers in cellular and infection microbiology - May 2, 2019 Category: Microbiology Source Type: research

Interplay Between Toxoplasma gondii, Autophagy, and Autophagy Proteins
This article provides an overview of this interplay with an emphasis on autophagy. Lysosomal degradation is an important mechanism of defense against numerous pathogens. This can be accomplished not only through the endocytic pathway but also through macroautophagy (called herein autophagy) (Levine et al., 2011). Autophagy is a homeostatic mechanism whereby large portions of cytosol or entire organelles are encircled by a double membrane (isolation membrane) leading to the formation of an autophagosome (Klionsky and Emr, 2000; Yoshimori, 2004; Mizushima et al., 2010). This structure fuses with lysosomes resulting in...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Toxoplasma Hypervirulence in the Rat Model Parallels Human Infection and Is Modulated by the Toxo1 Locus
Corinne Loeuillet1, Anais Mondon1, Salima Kamche1, Véronique Curri2, Jean Boutonnat2,3, Pierre Cavaillès1 and Marie-France Cesbron-Delauw1* 1BNI Team, Grenoble Alpes, CNRS, Grenoble INP, TIMC-IMAG, Grenoble, France 2Therex Team, Grenoble Alpes, CNRS, Grenoble INP, TIMC-IMAG, Grenoble, France 3Unit of Anatomopathology, Institute of Biology and Pathology, Grenoble Alpes Hospital, Grenoble, France Toxoplasmosis is considered as an opportunistic parasitic disease. If post-natally acquired in children or adults, it may pass unnoticed, at least with strains of European origin. However, in the wild bioto...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

A Multi-Stage Plasmodium vivax Malaria Vaccine Candidate Able to Induce Long-Lived Antibody Responses Against Blood Stage Parasites and Robust Transmission-Blocking Activity
This study including human samples was carried out in accordance with the recommendations of the ICH/GCP guidelines, Comité de Etica para Investigación con Humanos, Centro Internacional de Vacunas (CECIV, Cali, Colombia), and the protocol approved by the CECIV. All subjects gave written informed consent in accordance with the Declaration of Helsinki. All animal protocols that include experimental animal procedures using mice and NHP were carried out in accordance with the US Animal Welfare Act and approved by the Emory University's Institutional Animal Care and Use Committee and followed accordingly....
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

The Current Evidence on the Association Between the Urinary Microbiome and Urinary Incontinence in Women
This study also found that Proteus DNA, a genus with many uropathogenic species (Drzewiecka, 2016), was more prevalent in women with OAB compared to asymptomatic controls (Curtiss et al., 2017). IC A recent study by Abernethy et al. suggested that the microbiome may play a role in IC (Abernethy et al., 2017). In this study, 16S rRNA analysis determined the microbiome of catheterized urine from women (n = 40) with IC was not dominated by a single genus and was less likely to contain Lactobacillus compared to asymptomatic women. Abernethy et al. also showed that L. acidophilus was associated with less severe scores on the ...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Toxoplasma gondii: CD8 T Cells Cry for CD4 Help
Conclusions Toxoplasma gondii infection induces a strong innate and adaptive immune response. While the innate immunity is important for controlling the early stages of the infection (Yarovinsky, 2014), the adaptive immunity is critical for restricting the parasite replication during the later stages (Gazzinelli et al., 1992). Amongst the adaptive immune subsets, CD8 T cells are the primary effector cells while CD4 T cells play an essential helper role to maintain long-term immunity (Casciotti et al., 2002). Notwithstanding, a robust CD8 T cell immunity induced during acute phase of infection, does not result in the total...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Toxoplasma Effector GRA15-Dependent Suppression of IFN- γ-Induced Antiparasitic Response in Human Neurons
Toxoplasma Effector GRA15-Dependent Suppression of IFN-γ-Induced Antiparasitic Response in Human Neurons Hironori Bando1,2, Youngae Lee1,2, Naoya Sakaguchi1, Ariel Pradipta1, Ryoma Sakamoto1, Shun Tanaka1, Ji Su Ma1,2, Miwa Sasai1,2 and Masahiro Yamamoto1,2* 1Department of Immunoparasitology, Research Institute for Microbial Diseases, Suita, Japan 2Laboratory of Immunoparasitology, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan Toxoplasma gondii is an important human and animal pathogen that causes life-threatening toxoplasmosis. The host immune system produces interferon-γ (I...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Vibrio Flagellar Synthesis
Mylea A. Echazarreta and Karl E. Klose* Department of Biology, South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, United States Vibrio spp. are highly motile Gram-negative bacteria, ubiquitously found in aquatic environments. Some Vibrios are responsible for disease and morbidity of marine invertebrates and humans, while others are studied for their symbiotic interactions. Vibrio spp. are motile due to synthesis of flagella that rotate and propel the bacteria. Many Vibrio spp. synthesize monotrichous polar flagella (e.g., V. cholerae, V. alginolyticus); howev...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Integrative Analyses of Long Non-coding RNA and mRNA Involved in Piglet Ileum Immune Response to Clostridium perfringens Type C Infection
In conclusion, the results improve our understanding on the characteristics of lncRNAs and mRNAs on regulating host immune response against C. perfringens type C infection, which will provide a reference for future research into exploring C. perfringens-related diseases in human. Introduction Clostridium perfringens (C. perfringens) is a Gram-positive anaerobic rod and ranks as the second most common bacteria that causes fulminant, fatal infectious and immune diseases (Scharff, 2012; Grass et al., 2013). These diseases are characterized by fever, pain, gas production, local edema, and severe tissue destruction, the...
Source: Frontiers in cellular and infection microbiology - May 1, 2019 Category: Microbiology Source Type: research

Herpes Simplex Virus Evasion of Early Host Antiviral Responses
Eduardo I. Tognarelli1, Tomás F. Palomino1, Nicolás Corrales1, Susan M. Bueno1, Alexis M. Kalergis1,2 and Pablo A. González1* 1Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile 2Departamento de Endocrinología, Facultad de Medicina, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) have co-evolved with humans for thousands o...
Source: Frontiers in cellular and infection microbiology - April 30, 2019 Category: Microbiology Source Type: research

Application of Antimicrobial Peptides of the Innate Immune System in Combination With Conventional Antibiotics —A Novel Way to Combat Antibiotic Resistance?
Application of Antimicrobial Peptides of the Innate Immune System in Combination With Conventional Antibiotics—A Novel Way to Combat Antibiotic Resistance? Maria S. Zharkova1, Dmitriy S. Orlov1, Olga Yu. Golubeva2, Oleg B. Chakchir3, Igor E. Eliseev3, Tatyana M. Grinchuk4 and Olga V. Shamova1* 1Laboratory of Design and Synthesis of Biologically Active Peptides, Department of General Pathology and Pathophysiology, FSBSI Institute of Experimental Medicine, Saint Petersburg, Russia 2Laboratory of Nanostructures Research, Institute of Silicate Chemistry of the Russian Academy of Sciences, Saint Petersburg, Russia ...
Source: Frontiers in cellular and infection microbiology - April 30, 2019 Category: Microbiology Source Type: research

A Pertussis Outer Membrane Vesicle-Based Vaccine Induces Lung-Resident Memory CD4 T Cells and Protection Against Bordetella pertussis, Including Pertactin Deficient Strains
In this study we have evaluated whether our OMVs vaccine is capable of overcoming the deficiencies of commercial vaccines in both controlling infections caused by PRN(-) isolate/strain and inducing memory immunity. We found that our OMVs-based formulation has a higher protective capacity against the PRN(-) bacteria than that induced with a commercial aP vaccine. We found that CD4 T cells with a tissue-resident memory (TRM) cell phenotype (CD44+CD62LlowCD69+ and/or CD103+) accumulated in the lungs of mice after the second OMVs vaccine immunization. CD4 TRM cells were also detected in mice immunized with wP vaccine, but not ...
Source: Frontiers in cellular and infection microbiology - April 26, 2019 Category: Microbiology Source Type: research

Genomic and Epidemiological Evidence of a Dominant Panton-Valentine Leucocidin-Positive Methicillin Resistant Staphylococcus aureus Lineage in Sri Lanka and Presence Among Isolates From the United Kingdom and Australia
Conclusions: We present the most detailed genomic analysis of MRSA isolated in Sri Lanka to date. The analysis identified a PVL-positive ST5-MRSA-IVc that is prevalent among MRSA causing clinical infections in Sri Lanka. Furthermore, this clone was also found among isolates from the United Kingdom and Australia. Introduction Worldwide, Staphylococcus aureus is the primary causative agent of community-acquired skin and soft tissue infections (SSTI) and is an important cause of hospital-associated invasive infections including bacteremia, pneumonia and endocarditis (Bell et al., 2002; David and Daum, 2010). Panton-Va...
Source: Frontiers in cellular and infection microbiology - April 26, 2019 Category: Microbiology Source Type: research

Gene Disruption of Honey Bee Trypanosomatid Parasite, Lotmaria passim, by CRISPR/Cas9 System
In this study, we first generated L. passim clone expressing fluorescent marker and then attempted to use CRISPR/Cas9 for the genome editing. We will discuss how these approaches can be used to better understand honey bee-trypanosomatid parasite interactions. Materials and Methods Culture of L. passim Lotmaria passim strain SF (PRA-403) was obtained from the American Type Culture Collection (ATCC) and cultured in the modified FP-FB medium (Salathe et al., 2012) at 25°C without CO2. To monitor the growth rate of L. passim, the parasites were first inoculated at 5 × 105/mL and their number during the culture was...
Source: Frontiers in cellular and infection microbiology - April 26, 2019 Category: Microbiology Source Type: research

The Role of the Cell Surface Mucin MUC1 as a Barrier to Infection and Regulator of Inflammation
Poshmaal Dhar1 and Julie McAuley2* 1Faculty of Health, School of Medicine, Deakin University, Geelong, VIC, Australia 2Department of Microbiology and Immunology, Peter Doherty Institute, University of Melbourne, Melbourne, VIC, Australia The family of cell surface (cs-) mucins are constitutively expressed at the cell surface by nearly all epithelial cells, beneath the gel-mucin layer. All cs-mucin family members have structural features that enable them to act as a releasable decoy barrier to mucosal pathogens, by providing ligands for pathogen binding and the ability to shed the bound extracellular domain. Due ...
Source: Frontiers in cellular and infection microbiology - April 24, 2019 Category: Microbiology Source Type: research

Physical Extraction and Fast Protein Liquid Chromatography for Purifying Flagella Filament From Uropathogenic Escherichia coli for Immune Assay
In this study, we sought to establish a new, carefully optimized method to extract and purify non-denatured, native FliC from the reference UPEC strain CFT073 to be suitable for immune assays. To achieve purification of FliC to homogeneity, we used a mutant CFT073 strain containing deletions in four major chaperone-usher fimbriae operons (type 1, F1C and two P fimbrial gene clusters; CFT073Δ4). A sequential flagella extraction method based on mechanical shearing, ultracentrifugation, size exclusion chromatography, protein concentration and endotoxin removal was applied to CFT073Δ4. Protein purity and integrity ...
Source: Frontiers in cellular and infection microbiology - April 24, 2019 Category: Microbiology Source Type: research

Molecular Characterization of Fructose-1,6-bisphosphate Aldolase From Trichinella spiralis and Its Potential in Inducing Immune Protection
Yong Yang1,2†, Xue Bai1†, Chengyao Li1†, Mingwei Tong3, Peihao Zhang2, Wei Cai4, Xiaolei Liu1* and Mingyuan Liu1,5* 1Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Institute of Zoonosis, Jilin University, Changchun, China 2Wu Xi Medical School, Jiangnan University, Wuxi, China 3School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China 4Affiliated Hospital of Jiangnan University, The Fourth People's Hospital of Wuxi City, Wuxi, China 5Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Di...
Source: Frontiers in cellular and infection microbiology - April 24, 2019 Category: Microbiology Source Type: research