Vol 9: Diversifying Selection on the Thrombospondin-Related Adhesive Protein (TRAP) Gene of Plasmodium falciparum in Thailand.. This article is from PLoS ONE, volume 9.AbstractSporozoites of Plasmodium falciparum are transmitted to human hosts by A. Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
Micronemes are cellular organs, or organelles, possessed by Apicomplexa protozoans that are restricted to the apical third of the protozoan body. They are surrounded by a typical unit membrane. On electron microscopy they have an electron-dense matrix due to the high protein content. They are specialized secretory organelles important for gliding motility and host cell invasion. These organelles secrete several proteins such as the Plasmodium falciparum apical membrane antigen-1, or PfAMA1, and Erythrocyte family antigen, or EBA, family proteins. These proteins specialize in binding to erythrocyte surface receptors and facilitating erythrocyte entry. Only by this initial chemical exchange can the parasite enter into the erythrocyte via actin-myosin motor complex. It has been posited that this organelle works cooperatively with its counterpart organelle, the rhoptry, which also is a secretory organelle. It is possible that, while the microneme initiates erythrocyte-binding, the rhoptry secretes ...
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4F1K: Structure of Plasmodium falciparum TRAP (thrombospondin-related anonymous protein) A domain highlights distinct features in apicomplexan von Willebrand factor A homologues.
The gene product of the cytoadherence-linked asexual gene 9 (clag9) (64) was used as a second rhoptry-specific marker. CLAG9 was previously localized exclusively to the bulb of the rhoptry (31). The distribution of CLAG9 predominantly overlaps with that of RALP1 (Fig. 5B). In contrast, the apical distribution of RALP1 was clearly distinct from that of the micronemal marker proteins EBA-175 and EBA-181 (19, 53) (Fig. 5C and D). Together, these findings establish RALP1 as a novel rhoptry-resident protein. ...
The gene product of the cytoadherence-linked asexual gene 9 (clag9) (64) was used as a second rhoptry-specific marker. CLAG9 was previously localized exclusively to the bulb of the rhoptry (31). The distribution of CLAG9 predominantly overlaps with that of RALP1 (Fig. 5B). In contrast, the apical distribution of RALP1 was clearly distinct from that of the micronemal marker proteins EBA-175 and EBA-181 (19, 53) (Fig. 5C and D). Together, these findings establish RALP1 as a novel rhoptry-resident protein. ...
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a family of proteins present on the membrane surface of red blood cells (RBCs or erythrocytes) that are infected by the malarial parasite Plasmodium falciparum. PfEMP1 is synthesized during the parasites blood stage (erythrocytic schizogony) inside the RBC, during which the clinical symptoms of falciparum malaria are manifested. Acting as both an antigen and adhesion protein, it is thought to play a key role in the high level of virulence associated with P. falciparum. It was discovered in 1984 when it was reported that infected RBCs had unusually large-sized cell membrane proteins, and these proteins had antibody-binding (antigenic) properties. An elusive protein, its chemical structure and molecular properties were revealed only after a decade, in 1995. It is now established that there is not one but a large family of PfEMP1 proteins, genetically regulated (encoded) by a group of about 60 genes called var. Each P. falciparum is ...
Link to Pubmed [PMID] - 12802682. Parasitol. Res. 2003 Aug;90(6):467-72. Plasmodium falciparum parasites remodel the surface of human erythrocytes on invasion by the insertion of parasite-derived proteins in knob-like protrusions. P. falciparum erythrocyte membrane protein 1 (PfEMP-1), a variant surface antigen, has been shown to be anchored in these knobs and mediates adhesion to various host endothelial receptors. These proteins also undergo clonal antigenic variation as a means of immune evasion. Duffy binding-like-alpha(DBL-alpha) domain together with the cysteine-rich interdomain region form the head structure of the PfEMP1 molecule. In this report, we used ten different recombinant DBL-alpha fusion proteins expressed in Escherichia coli to generate antibodies in experimental animals. Five out of ten recombinant DBL-alpha fusion proteins were immunogenic and induced antibodies that reacted with conserved peptides derived from PfEMP1. Indirect immunofluorescence assay was used to localise ...
Emerging evidence suggests that antibodies against merozoite proteins involved in Plasmodium falciparum invasion into the red blood cell (RBC) play an important role in clinical immunity to malaria. The protein family of parasite antigens known as P. falciparum reticulocyte binding protein like homolog (PfRh) is required for RBC invasion. PfRh5 is the only member within the PfRh family that cannot be genetically deleted, suggesting it plays an essential role in parasite survival. This antigen forms a complex with the cysteine-rich P. falciparum Rh5 interacting protein (PfRipr), on the merozoite surface during RBC invasion. The PfRh5 ectodomain sequence and a C-terminal fragment of PfRipr were cloned and expressed in Escherichia coli and baculovirus-infected cells, respectively. Immunization of rabbits with these recombinant proteins induced antibodies able to inhibit growth of various P. falciparum strains. Antibody responses to these proteins were investigated in a treatment re-infection study ...
Looking for online definition of apical complex in the Medical Dictionary? apical complex explanation free. What is apical complex? Meaning of apical complex medical term. What does apical complex mean?
Malaria presents a considerable threat to public health. Histidine-rich protein 2 (HRP 2) is the major protein released into human blood upon infection by Plasmodium falciparum. In this study, we aimed to evaluate the immunogenicity of HRP 2 exon II and the efficacy of novel monoclonal antibodies (mAbs) against HRP 2 for Point-of-Care Test (POCT). The recombinant protein was expressed in soluble form in E. coli and used to immunize mice for mAb production. Two IgG1 mAbs (1A5 and 1C10) with high affinity, specificity and sensitivity for both native and recombinant HRP 2 were selected after fusion of mouse spleen with myeloma cells. The affinity constant of 1A5 and 1C10 were 7.15 and 4.91 × 10-7 L/mol, respectively. Subsequently, an immunochromatograhic assay was used for screening of clinical samples in endemic regions of China and Myanmar. The immunochromatographic test retrospectively showed an overall sensitivity of 99.07%, and specificity of 100%. Sensitivity at parasite densities | 200, 200-2000,
A clone of complementary DNA encoding the circumsporozoite (CS) protein of the human malaria parasite Plasmodium falciparum has been isolated by screening an Escherichia coli complementary DNA library with a monoclonal antibody to the CS protein. The DNA sequence of the complementary DNA insert encodes a four-amino acid sequence: proline-asparagine-alanine-asparagine, tandemly repeated 23 times. The CS beta-lactamase fusion protein specifically binds monoclonal antibodies to the CS protein and inhibits the binding of these antibodies to native Plasmodium falciparum CS protein. These findings provide a basis for the development of a vaccine against Plasmodium falciparum malaria. ...
Antibodies are known to play an important role in the control of malaria infection. Since the early studies demonstrating that antibodies transferred from immune individuals diminish P. falciparum parasitaemia [11] a lot of effort has been put forward to identify parasite epitopes and mechanisms of action of antibody-mediated immune response to malaria. Besides their role in infection control, antibodies can modulate parasite development in the sporogonic [3 - 5], exoerythrocytic [6] and erythrocytic [7] cycle. However, there is almost no information on the effect of antibodies on the expression of Plasmodium immunogenic molecules.. There are evidences that antibodies can interfere with parasite multiplication. An increase on sporozoite number recovered from the salivary glands when mosquitoes were fed on anti-Plasmodium antibodies was observed [3, 4] and IgG isolated from Kenyan immune adults enhanced parasite growth in culture while the serum from which they were isolated had an inhibitory ...
The clinical symptoms of malaria are attributed to the blood stage life cycle of parasite in which merozoite invades erythrocyte, undergoes multiplication and exit to re-invade into new erythrocyte to continue its life cycle. The interaction of repertoire of parasite proteins with host cell receptors is essential for invasion process. Identification, characterization and localization of the proteins involved in invasion will enrich our understanding of this complex process. In the present study we have identified a novel Apical Rhoptry Neck Protein in Plasmodium falciparum, which harbours a predicted signal and transmembrane domain and is conserved across the species. The transcription and translation analysis confirmed its expression in schizont stage of asexual cycle of P. falciparum. Immunoflouresence microscopy in schizonts and merozoites revealed its localization in the neck of rhoptries of P. falciparum. Furthermore, PfARNP has been found at the tight junction during invasion of P. ...
Placental malaria is typified by selective clustering of Plasmodium falciparum in the intervillous blood spaces of the placenta. Sequestration of malaria parasite in the human placenta is mediated by interactions between chondroitin sulphate A (CSA) on the syncytiotrophoblasts and proteins expressed on the surface of infected human erythrocytes. Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) encoded by the var2CSA gene is believed to be the main parasite ligand for CSA-mediated placental binding. Extensive sequence and structure comparisons of the various CSA-binding and non-binding DBL domains from the var2CSA gene from A4 and 3D7 strains of P. falciparum were performed. Three-dimensional structural models of various DBL domains were built and analysed with a view to assessing conservation of CSA interaction sites across various DBL domains. Each of the six DBL domains from var2CSA are likely to retain the disulfide linkages evident from previously published DBL domain crystal structures
Placental malaria is typified by selective clustering of Plasmodium falciparum in the intervillous blood spaces of the placenta. Sequestration of malaria parasite in the human placenta is mediated by interactions between chondroitin sulphate A (CSA) on the syncytiotrophoblasts and proteins expressed on the surface of infected human erythrocytes. Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) encoded by the var2CSA gene is believed to be the main parasite ligand for CSA-mediated placental binding. Extensive sequence and structure comparisons of the various CSA-binding and non-binding DBL domains from the var2CSA gene from A4 and 3D7 strains of P. falciparum were performed. Three-dimensional structural models of various DBL domains were built and analysed with a view to assessing conservation of CSA interaction sites across various DBL domains. Each of the six DBL domains from var2CSA are likely to retain the disulfide linkages evident from previously published DBL domain crystal structures
Looking for online definition of circumsporozoite protein in the Medical Dictionary? circumsporozoite protein explanation free. What is circumsporozoite protein? Meaning of circumsporozoite protein medical term. What does circumsporozoite protein mean?
Plasmodium falciparum synthesizes P. falciparum erythrocyte membrane protein-1 (PfEMP-1), a product of the multicopy var gene family, which localizes on the surface of infected erythrocytes. This protein plays an important role in cytoadherence and immune evasion. Comparative analysis of the molecular sequences of the DBLα domain of the var gene from different isolates of the parasite reveals variations in the number of cysteines and presence of small conserved motifs like DGEA, RGD, GAG-binding motifs. Phylogenetic analysis while highlighting the extensive diversity leads to clustered them in separate clades far apart from each other. Discriminant factor analysis of physicochemical properties of amino acid sequences revealed that the aliphatic index, isoelectric point, and instability index have more effect in deciding the variance of different isolates sequences. The origin of diverse repertoire of the DBLα domain in the parasites highlights the complexity of host-parasite relationship in ...
Antibodies can bind proteins via the Fab and Fc regions. The Fc interacts with receptors on the cells of the immune system causing effector responses such as phagocytosis and complement mediating lysis, however, pathogens have also developed a way to interact with human antibodies through regions on the Fc. We are currently trying to understand the mechanism underlying the binding of Plasmodium falciparum infected erythrocytes to IgM. The Cμ4 domain of multimeric IgM has been shown to bind to the C-terminal Duffy Binding Like (DBL) domains of Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) expressed by CSA-binding and rosetting strains of Plasmodium falciparum. CSA-binding has been linked to pregnancy associated malaria and rosetting (the binding of infected to uninfected erythrocytes) has been shown to correlate with many clinical manifestations of severe malaria in children living in sub-Saharan Africa. The binding of IgM has been termed as "non-immune" because its interaction ...
The most severe form of malaria in humans is caused by the intracellular parasite Plasmodium falciparum. The African continent bears the greatest burden of malaria with 90% of all malaria deaths occurring in sub-Saharan Africa where the high risk populations include pregnant woman and children under the age of five. Fatal cases of malaria are often a result of the progression of the disease to a life threatening syndrome where intravenous quinine or artesunate are administered as an emergency treatment, however a 15-20% mortality rate is still observed among treated individuals. Pathogenesis of severe malaria is associated with the mature or late trophozoite stage of the parasite s intra-erythrocyte life cycle. At this stage the intracellular parasite expresses parasite derived proteins on the surface of the red blood cell (RBCs) that bind to host endothelial receptors. This cytoadhesion ultimately allows the parasite to multiply unhindered by the host resulting in high parasitaemia levels which ...
We describe the cloning of a novel antigen of Plasmodium falciparum which contains a hydrophobic domain typical of an integral membrane protein. This antigen is designated apical membrane antigen 1 because it appears to be located in the apical complex. Apical membrane antigen 1 appears to be transported to the merozoite surface near the time of schizont rupture. ...
Adhesin proteins are used by Plasmodium parasites to bind and invade target cells. Hence, characterising molecules that participate in reticulocyte interaction is key to understanding the molecular basis of Plasmodium vivax invasion. This study focused on predicting functionally restricted regions of the P. vivax GPI-anchored micronemal antigen (PvGAMA) and characterising their reticulocyte binding activity. The pvgama gene was initially found in P. vivax VCG-I strain schizonts. According to the genetic diversity analysis, PvGAMA displayed a size polymorphism very common for antigenic P. vivax proteins. Two regions along the antigen sequence were highly conserved among species, having a negative natural selection signal. Interestingly, these regions revealed a functional role regarding preferential target cell adhesion. To our knowledge, this study describes PvGAMA reticulocyte binding properties for the first time. Conserved functional regions were predicted according to natural selection analysis and
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Five new articles published this week in PLOS Medicine ranging from malaria to HIV to cardiovascular health. Arjen Dondorp and colleagues investigate whether the plasma level of Plasmodium falciparum histidine-rich protein 2 can be ...
Many microneme proteins are secreted onto the parasite surface to play a role in host cell entry and then ultimately shed. This study demonstrates that EBA-175, and, by extrapolation, all other DBL-EBPs, are subject to a similar fate. Given their role in invasion and their capacity to bind erythrocyte surface receptors with high affinity, these ligands presumably function in membrane bound form at the merozoite surface. Our results show that the truncated form of EBA-175 released into supernatants is a result of a physiologically important, precise cleavage event that takes place at the merozoite surface and is mediated via intramembrane cleavage by a rhomboid-like malarial protease.. IFA of newly invaded rings showed that, irrespective of whether EBA-175 was used as the dominant invasion ligand, invasion is associated with shedding of EBA-175. Western blot showed that the shed protein retains much or all of region VI, and mass spectrometric analysis allowed us to map its C terminus to an Ala ...
The invasive stages (zoites) of most apicomplexan parasites are polarised cells that use their actinomyosin-powered gliding motility or
3. The differences between CDKs in mammals and those in human parasites. Both humans and protozoan parasites are eukaryotes, however they diverged long ago and belong to different phylogenetic kingdoms. The reproduction of a single-celled malarial parasite and that of a human or a human cell are very different processes, however they both use similar CDK machinery. The genome sequence of the malarial parasite Plasmodia falciparum has recently been finished and with it came the discovery of several homologs of the cyclin-dependent kinases and cyclins. I am working with several other groups to elucidate the differences between the mammalian CDKs and those of the parasite. There are two reasons for this study. First, we are currently trying to study these enzymes with an eye toward finding inhibitors which will stop the cell cycle of the parasite without stopping the cell cycle of the human host. This will hopefully lead to the development of malarial treatments. Second, evolutionarily, protists ...
3HGF: Structural determination of functional units of the nucleotide binding domain (NBD94) of the reticulocyte binding protein Py235 of Plasmodium yoelii
Identification of nuclear proteins that interact differentially with Plasmodium falciparum var gene promoters.: The Plasmodium falciparum virulence factor PfEMP
To investigate the role of the coreceptor CD8 and lipid rafts in cytotoxic T lymphocyte (CTL) activation, we used soluble mono-and multimeric H-2K,sup,d,/sup,-peptide complexes and cloned S14 CTL specific for a photoreactive derivative of the Plasmodium berghei circumsporozoite (PbCS) peptide 252-260 [PbCS(ABA)]. We report that activation of CTL in suspension requires multimeric K,sup,d,/sup,-PbCS(ABA) complexes co-engaging TCR and CD8. Using TCR ligand photo-cross-linking, we find that monomeric K,sup,d,/sup,-PbCS(ABA) complexes promote association of TCR/CD3 with CD8/p56,sup,lck,/sup,. Dimerization of these adducts results in activation of p56lck in lipid rafts, where phosphatases are excluded. Additional cross-linking further increases p56,sup,lck,/sup, kinase activity, induces translocation of TCR/CD3 and other signaling molecules to lipid rafts and intracellular calcium mobilization. These events are prevented by blocking Src kinases or CD8 binding to TCR-associated K,sup,d,/sup, molecules, ...
Stratmann, Thomas, Schmida, Stefanie R., Harperb, Jeffrey F. and Kang, Angray S. (1997) Bacterial expression and purification of recombinant Plasmodium yoelii circumsporozoite protein. Protein Expression and Purification, 11 (1). pp. 72-78. ISSN 1046-5928 ...
This gene encodes a glutamate-rich protein that contains five WD-repeat motifs. The encoded protein may play a critical role in ribosome biogenesis and may also play a role in histone methylation through interactions with CUL4-DDB1 ubiquitin E3 ligase. [provided by RefSeq, Feb 2012 ...
One of the key processes in the pathobiology of the malaria parasite is the invasion and subsequent modification of the human erythrocyte. In this complex process, an unknown number of parasite proteins are involved, some of which are leading vaccine candidates. The majority of the proteins that play pivotal roles in invasion are either stored in the apical secretory organelles or located on the s ...
Every month through fall, the government-funded COVID-19 Prevention Network will roll out a new study of a leading vaccine candidate - each with 30,000 new volunteers.
Every month through fall, the government-funded COVID-19 Prevention Network will roll out a new study of a leading vaccine candidate - each with 30,000 new volunteers.
Genes are transcribed in polysictronic messages (pre-mRNA) that are destined for either maturation into mRNAs, or degradation. Since transcription regulation is non-existent with few exceptions, the rate of pre-mRNA processing, together with mRNA decay and translation rates, are believed to control gene expression. In this assay, 2T1 blood form trypanosomes are subject to treatment by ActinomycinD for 5 minutes, inhibiting transcription. The cells are harvested, depleted for ribosomal RNA, and ...
If you havent heard ...according to vaccinews.net, but contrary to conventional medical literature, the CDC, and leading vaccine experts - the anti-vaccine
Here we review both the structural details and functional significance of interactions at the hydrophobic cleft of AMA1, and argue that this feature of the protein represents an excellent target for the development of drugs that would block host cell invasion by malarial parasites.. ...
Patel, A, Perrin, AJ, Flynn, HR, Bisson, C, Withers-Martinez, C, Treeck, M, Flueck, C, Nicastro, G, Martin, SR, Ramos, A, Gilberger, TW, Snijders, AP, Blackman, MJ and Baker, D (2019). Cyclic AMP signalling controls key components of malaria parasite host cell invasion machinery. [Data Collection]. PLoS Biology. https://doi.org/10.1371/journal.pbio.3000264 ...
In order to understand the mechanism of molecular interactions at the active site of Tryparedoxin Peroxidase (Try P), homology modeling and docking studies were performed. We generated a Three-Dimensional (3D) model of target protein based on the Crystal structure of Leishmania Major Try PI (PDB ID: 3TUE) using modeler software. Docking analysis was carried out to study the effects of methotrexate on Tryparedoxin Peroxidase (Try P). Inhibition of the Tryparedoxin peroxidase interaction has become a new therapeutic strategy in treating leishmaniasis. Docking analysis was carried out to study the effects of methotrexate on Tryparedoxin Peroxidase (TryP). Tryparedoxin peroxidase of Trypanosomatidae family functions as antioxidant through their peroxidase and peroxynitrite reductase activities. The theoretical docking study, conducted on a sample previously reported for anti-cancer properties of Methotrexate at the binding site of 3D models of Tryparedoxin Peroxidase of Leishmania braziliensis (L. ...
The flagellum is attached along the length of the cell body in the protozoan parasite Trypanosoma brucei and is a defining morphological feature of this parasite. The flagellum attachment zone (FAZ) is a complex structure and has been characterised morphologically as comprising a FAZ filament struct …
Sitta, T., Henson, S., Morrison, W.I. and Toye, P. 2019. Similar levels of diversity in the gene encoding the p67 sporozoite surface protein of Theileria parva are observed in blood samples from buffalo and cattle naturally infected from buffalo. Veterinary Parasitology 269:21-27 ...
Abs that inhibit Plasmodium falciparum invasion of erythrocytes form an important component of human immunity against malaria, but key target Ags are largely unknown. Phenotypic variation by P. falciparum mediates the evasion of inhibitory Abs, contributing to the capacity of P. falciparum to cause repeat and chronic infections. However, Ags involved in mediating immune evasion have not been defined, and studies of the function of human Abs are limited. In this study, we used novel approaches to determine the importance of P. falciparum erythrocyte-binding Ags (EBAs), which are important invasion ligands, as targets of human invasion-inhibitory Abs and define their role in contributing to immune evasion through variation in function. We evaluated the invasion-inhibitory activity of acquired Abs from malaria-exposed children and adults from Kenya, using P. falciparum with disruption of genes encoding EBA140, EBA175, and EBA181, either individually or combined as EBA140/EBA175 or EBA175/EBA181 double
Link to Pubmed [PMID] - 25522250. PLoS Pathog. 2014 Dec;10(12):e1004520. All pathogenesis and death associated with Plasmodium falciparum malaria is due to parasite-infected erythrocytes. Invasion of erythrocytes by P. falciparum merozoites requires specific interactions between host receptors and parasite ligands that are localized in apical organelles called micronemes. Here, we identify cAMP as a key regulator that triggers the timely secretion of microneme proteins enabling receptor-engagement and invasion. We demonstrate that exposure of merozoites to a low K+ environment, typical of blood plasma, activates a bicarbonate-sensitive cytoplasmic adenylyl cyclase to raise cytosolic cAMP levels and activate protein kinase A, which regulates microneme secretion. We also show that cAMP regulates merozoite cytosolic Ca2+ levels via induction of an Epac pathway and demonstrate that increases in both cAMP and Ca2+ are essential to trigger microneme secretion. Our identification of the different ...
A procyclic acidic repetitive protein (PARP) fraction was purified from long-term cultures of Trypanosoma brucei procyclic forms by a solvent-extraction and reverse phase chromatography procedure. The PARP fraction yielded small quantities of a single N-linked oligosaccharide with the structure Man alpha1-6(Man alpha1-3)Man alpha1-6(Man alpha1-3)Manbeta1-4GlcNAcbeta1-4GlcNAc (Man5GlcNAc2). Fractionation of PARP on Con A-Sepharose revealed that the majority (80 to 90%) of the PARP fraction did not bind to Con A and was composed of the parpA alpha gene product that contains repeats of -Glu-Pro-Pro-Thr- (GPEET-PARP) and that lacks an N-glycosylation site. This form of PARP has not been previously identified at the protein-level. The minor Con-A-binding fraction was shown to be rich in the previously described form of PARP, encoded by the parpAbeta and/or parpB alpha genes, that contains a -Glu-Pro- repeat domain (EP-PARP) and an N-glycosylation site. Analysis of longer and shorter-term cultures suggested
Abstract An ELISA employing a novel synthetic peptide consisting of 40 (Asn-Ala-Asn-Pro) repeats of Plasmodium falciparum circumsporozoite protein, (NANP)40, was used to detect antibodies against P. falciparum circumsporozoite protein in 132 children, 1 month to 15 years old, from a rural community (Kikwawila village) of Tanzania, a region where malaria is hyperendemic. The children were surveyed comprehensively over 3 consecutive years for clinical, parasitological, and serological parameters. Entomological data were also gathered for selected households in this village. The following results were obtained: anti-(NANP)40 antibodies increased as a function of age; the majority of children over 10 years showed a stable positivity for such antibodies during the longitudinal study; a negative correlation was observed between the levels of anti-sporozoite antibodies and both spleen enlargement and the presence of parasites in thick smears; no relationship was found between anti-(NANP)40 antibodies and
Toxoplasma gondii and Plasmodium species are obligate intracellular pathogens that utilize host sugars for energy homeostasis and macro molecular synthesis. Here, we report that the T. gondii glucose transporter, TgGT1, and of its homologs of P. falciparum and P. berghei (PfHT1 and PbHT1) transport glucose, mannose, galactose and fructose. Besides TgGT1, Toxoplasma harbours one additional surface localized putative sugar transporter (TgST2). Surprisingly both Proteins are nonessential and only the deletion of TgGT1 inflicts a mild defect in the parasite replication. The ?tggt1 mutant is unable to import glucose and consequently displays an attenuated glucose-dependent motility, which is completely rescued by glutamine. ?tggt1 performs increased glutamine metabolism that is sufficient to sustain motility and replication. The ?tggt1 strain provides a model for further investigating its adaptation to disparate host cells. In contrast to T. gondii, erythrocytic stages of Plasmodium species ...
No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC(50) values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte
Toxoplasma gondii possesses a highly polarized secretory system, which efficiently assembles de novo micronemes and rhoptries during parasite replication. These apical secretory organelles release their contents into host cells promoting parasite invasion and survival. Using a CreLox-based inducible knock-out strategy and the ddFKBP over-expression system, we unraveled novel functions of the clathrin adaptor complex TgAP1. First, our data indicate that AP1 in T. gondii likely functions as a conserved heterotetrameric complex composed of the four subunits γ, β, μ1, σ1 and interacts with known regulators of clathrin-mediated vesicular budding such as the unique ENTH-domain containing protein, which we named Epsin-like protein (TgEpsL). Disruption of the μ1 subunit resulted in the mis-sorting of microneme proteins at the level of the Trans-Golgi-Network (TGN). Furthermore, we demonstrated that TgAP1 regulates rhoptry biogenesis by activating rhoptry protein exit from the TGN, but also ...
TY - JOUR. T1 - Pleiotropic effect due to targeted depletion of secretory rhoptry protein ROP2 in Toxoplasma gondii. AU - Nakaar, Valerian. AU - Ngô, Huân M.. AU - Aaronson, Emily P.. AU - Coppens, Isabelle. AU - Stedman, Timothy T.. AU - Joiner, Keith A. PY - 2003/6/1. Y1 - 2003/6/1. N2 - Long after their discovery, the function and biogenesis of rhoptries remain enigmatic. In Apicomplexan parasites, these organelles discharge and their contents are exocytosed at the time of host cell invasion, and are thus proposed to play an essential role in establishing the parasitophorous vacuole. In Toxoplasma gondii, ROP2 is suspected to serve as the molecular link between host cell mitochondria and parasitophorous vacuole membrane. In this study we addressed the function of ROP2. Targeted depletion of ROP2 using a ribozyme-modified antisense RNA strategy resulted in multiple effects on parasite morphology because of a disruption in the formation of mature rhoptries, and an arrest in cytokinesis. The ...
Human malaria is a devastating disease and a major cause of poverty in resource-limited countries. To develop and adapt within hosts Plasmodium falciparum undergoes drastic switches in gene expression. To identify regulatory regions in the parasite genome, we performed genome-wide profiling of chromatin accessibility in two culture-adapted isogenic subclones at four developmental stages during the intraerythrocytic cycle by using the Assay for Transposase-Accessible Chromatin by sequencing (ATAC-seq). Tn5 transposase hypersensitivity sites (THSSs) localize preferentially at transcriptional start sites (TSSs). Chromatin accessibility by ATAC-seq is predictive of active transcription and of the levels of histone marks H3K9ac and H3K4me3. Our assay allows the identification of novel regulatory regions including TSS and enhancer-like elements. We show that the dynamics in the accessible chromatin profile matches temporal transcription during development. Motif analysis of stage-specific ATAC-seq ...
A 195,000 mol wt Plasmodium falciparum protein and processing fragments derived from it have been purified by monoclonal antibody affinity chromatography. A polyvalent antiserum has been raised against the purified protein and used to identify the terminal processing products associated with the merozoite. Three unique fragments of 83,000, 42,000, and 19,000 mol wt are present and they represent the major surface antigens of P. falciparum merozoites. ...
Immunoepidemiological studies typically reveal slow, age-dependent acquisition of immune responses against Plasmodium falciparum sporozoites. Naturally acquired immunity against preerythrocytic stages is considered inadequate to confer protection against clinical malaria. To explore previously unrecognized antisporozoite responses, we measured serum levels of naturally acquired antibodies to whole Plasmodium falciparum sporozoites (Pfspz) and the immunodominant (NANP)5 repeats of the major sporozoite surface protein, circumsporozoite protein, in a well-characterized Kenyan cohort. Sera were sampled at the start of the malaria transmission season, and all subjects were prospectively monitored for uncomplicated clinical malaria in the ensuing 6 months. We used Kaplan-Meier analysis and multivariable regression to investigate the association of antisporozoite immunity with incidence of clinical malaria. Although naturally acquired humoral responses against Pfspz and (NANP)5 were strongly correlated (p | 0
Toxoplasma gondii is a protozoan pathogen that produces severe disease in humans and animals. This obligate intracellular parasite provides an excellent model for the study of how such pathogens are able to invade, survive, and replicate intracellularly. DNA encoding chloramphenicol acetyltransferase was introduced into T. gondii and transiently expressed with the use of three vectors based on different Toxoplasma genes. The ability to introduce genes and have them efficiently and faithfully expressed is an essential tool for understanding the structure-function relation of genes and their products. ...
Toxoplasma gondii microneme proteins (TgMICs), secreted by micronemes upon contact with host cells, are reported to play important roles in multiple stages of the T. gondii life cycle, including parasite motility, invasion, intracellular survival, and egress from host cells. Meanwhile, during these processes, TgMICs participate in many protein-protein and protein-carbohydrate interactions, such as undergoing proteolytic maturation, binding to aldolase, engaging the host cell receptors and forming the moving junction (MJ), relying on different types of ectodomains, transmembrane (TM) domains and cytoplasmic domains (CDs). In this review, we summarize the research advances in protein-protein and protein-carbohydrate interactions related to TgMICs, and their intimate associations with corresponding biological processes during T. gondii infection, which will contribute to an improved understanding of the molecular pathogenesis of T. gondii infection, and provide a basis for developing effective ...
Toxoplasma rhoptries, an unusual set of apical organelles that are associated with Toxoplasma infection may cause subversion of the host cell functions. Parasite rhoptry protein 16 (ROP16) is a ...
In Plasmodium falciparum infections the parasite transmission stages, the gametocytes, mature in 10 days sequestered in internal organs. Recent studies suggest that cell mechanical properties rather than adhesive interactions play a role in sequestration during gametocyte maturation. It remains instead obscure how sequestration is established, and how the earliest sexual stages, morphologically similar to asexual trophozoites, modify the infected erythrocytes and their cytoadhesive properties at the onset of gametocytogenesis. Here, purified P. falciparum early gametocytes were used to ultrastructurally and biochemically analyse parasite-induced modifications on the red blood cell surface and to measure their functional consequences on adhesion to human endothelial cells. This work revealed that stage I gametocytes are able to deform the infected erythrocytes like asexual parasites, but do not modify its surface with adhesive knob structures and associated proteins. Reduced levels of the P. ...
Despite considerable efforts toward vaccine development over decades, there is no available effective vaccine against Plasmodium vivax. Thrombospondin-related adhesive protein of P. vivax (PvTRAP) is essential for sporozoite motility and invasions into mosquitos salivary gland and vertebrates hepa …
In this study we show that the rhoptry-derived protein ROP2, the founding member of a family of rhoptry proteins exposed to the host cell cytosol (Beckers et al., 1994), mediates PVM-organelle association. This is achieved by the host cytoplasm-exposed domain, ROP2hc, inserting into organelle membranes and establishing a stable association. Despite possessing an NH2-terminal signal (Fig. 3 A; Beckers et al., 1994) with features on a matrix targeting signal (Neupert, 1997), ROP2hc insertion and translocation into the MOM (Fig. 3) does not occur by the conventional import pathway (Fig. 4). By what alternative mechanism is ROP2hc translocated across the MOM? ROP2hc import, presumably exposing its NH2 terminus to the intermembrane space (IMS), has features reminiscent of apocytochrome c import (Stuart and Neupert, 1990; Jordi et al., 1992; Dumont, 1996). ROP2hc shares some potentially important physical features with the IMS-localized cytochrome c and its receptor cytochrome c heme lyase (CCHL) ...
Copyright 2013 by the Massachusetts General Hospital. Some sections copyright 2008-2009 by The President and Fellows of Harvard College.. ...
We report the expression and purification of recombinant rodent malarialPlasmodium yoeliicircumsporozoite surface protein (PyCSP) inEscherichia coli.To facilitate purification of the recombinant protein, the PyCSP was expressed as an amino-terminal fusion protein to glutathioneS-transferase and as a carboxy-terminal fusion protein to a hexahistidyl tag. The expression of the fusion protein was controlled by the inducibletacpromoter. Under optimal conditions the immunoreactive PyCSP represented approximately 0.04% of the total cell lysate. Western blot analysis probing with an anti-PyCSP antibody revealed a wide array of immunoreactive bands. Material isolated by affinity purification on glutathione-Sepharose 4B resin also contained multiple bands indicative of premature termination or carboxyl-terminal degradation. Analysis of protein retained on a nickel nitrilotriacetic acid resin revealed evidence of amino-terminal deleted material. Combining the two mild affinity purifications resulted in ...
Author Summary Malaria is a devastating parasitic disease caused by the protozoan protist Plasmodium falciparum. The complex life cycle of P. falciparum comprises various morphological and functionally distinct forms and is completed in two different hosts. Various regulatory mechanisms are employed by these parasites to complete their life cycle and survive in human hosts. Epigenetic mechanisms, though not fully explored, have been implicated as one of the key players in gene regulation, morphological differentiation and antigenic variation. Here, we present a comprehensive epigenetic map of 12 histone post-translational modifications during the intraerythrocytic life cycle of P. falciparum. We have been able to identify at least eight histone modifications whose dynamic patterns correlate with the transcriptional regulation across the life cycle. In particular, we have shown that a set of euchromatic histone marks work in synergy, creating a dynamic unique histone code that is linked with gene
Molecular genetic studies of the human malaria parasite Plasmodium falciparum have been hampered in part due to difficulties in stably cloning and propagating parasite genomic DNA in bacteria. This is thought to be a result of the unusual A+T bias (|80%) in the parasites DNA. Pulsed-field gel electrophoretic separation of P. falciparum chromosomes has shown that large chromosomal polymorphisms, resulting from the deletion of DNA from chromosome ends, frequently occur. Understanding the biological implications of this chromosomal polymorphism will require the analysis of large regions of genomic, and in particular telomeric, DNA. To overcome the limitations of cloning parasite DNA in bacteria, we have cloned genomic DNA from the P. falciparum strain FCR3 in yeast as artificial chromosomes. A pYAC4 library with an average insert size of approximately 100 kb was established and found to have a three to fourfold redundancy for single-copy genes. Unlike bacterial hosts, yeast stably maintain and propagate
BACKGROUND: Malaria in pregnancy has major impacts on mother and child health. To complement existing interventions, such as intermittent preventive treatment and use of impregnated bed nets, we developed a malaria vaccine candidate with the aim of reducing sequestration of asexual "blood-stage" parasites in the placenta, the major virulence mechanism.. METHODS: The vaccine candidate PAMVAC is based on a recombinant fragment of VAR2CSA, the Plasmodium falciparum protein responsible for binding to the placenta via chondroitin sulfate A (CSA). Healthy, adult malaria-naive volunteers were immunized with 3 intramuscular injections of 20 μg (n = 9) or 50 μg (n = 27) PAMVAC, adjuvanted with Alhydrogel or glucopyranosyl lipid adjuvant in stable emulsion (GLA-SE) or in a liposomal formulation with QS21 (GLA-LSQ). Allocation was random and double blind. The vaccine was given every 4 weeks. Volunteers were observed for 6 months following last immunization.. RESULTS: All PAMVAC formulations were safe and ...
TY - JOUR. T1 - Distinct physiological states of Plasmodium falciparum in malaria-infected patients. AU - Daily, Johanna P.. AU - Scanfeld, D.. AU - Pochet, N.. AU - Le Roch, K.. AU - Plouffe, D.. AU - Kamal, M.. AU - Sarr, O.. AU - Mboup, S.. AU - Ndir, O.. AU - Wypij, D.. AU - Levasseur, K.. AU - Thomas, E.. AU - Tamayo, P.. AU - Dong, C.. AU - Zhou, Y.. AU - Lander, E. S.. AU - Ndiaye, D.. AU - Wirth, D.. AU - Winzeler, E. A.. AU - Mesirov, J. P.. AU - Regev, A.. PY - 2007/12/13. Y1 - 2007/12/13. N2 - Infection with the malaria parasite Plasmodium falciparum leads to widely different clinical conditions in children, ranging from mild flu-like symptoms to coma and death. Despite the immense medical implications, the genetic and molecular basis of this diversity remains largely unknown. Studies of in vitro gene expression have found few transcriptional differences between different parasite strains. Here we present a large study of in vivo expression profiles of parasites derived directly from ...
The social amoeba Dictyostelium discoideum is a well-established model organism to study the interaction between bacteria and phagocytes. In contrast, research using D. discoideum as a host model for fungi is rare. We describe a comprehensive study, which uses D. discoideum as a host model system to investigate the interaction with apathogenic (Saccharomyces cerevisiae) and pathogenic (Candida sp.) yeast. We show that Dictyostelium can be co-cultivated with yeasts on solid media, offering a convenient test to study the interaction between fungi and phagocytes. We demonstrate that a number of D. discoideum mutants increase (atg1-, kil1-, kil2-) or decrease (atg6-) the ability of the amoebae to predate yeast cells. On the yeast side, growth characteristics, reduced phagocytosis rate, as well as known virulence factors of C. albicans (EFG1, CPH1, HGC1, ICL1) contribute to the resistance of yeast cells against predation by the amoebae. Investigating haploid C. albicans strains, we suggest using the amoebae
Monoclonal antibody against Cortexillin I expressed by ctxA for use in Function Blocking, Immunohistochemistry, Western Blot against Dictyostelium
3.A.26 The Plasmodium Translocon of Exported Proteins (PTEX) Family Protein export is central for the survival and virulence of intracellular Plasmodium falciparum blood stage parasites. To reach the host cell, exported proteins cross the parasite plasma membrane (PPM) and the parasite-enclosing parasitophorous vacuole membrane (PVM), a process that requires unfolding, suggestive of protein translocation. Components of a proposed translocon at the PVM termed PTEX are essential in this phase of export, but questions have been raised about its proposed membrane pore component EXP2 for which little functional data are available in P. falciparum. It is also unclear how PTEX mediates trafficking of both soluble and transmembrane proteins. Taking advantage of conditionally foldable domains, Mesén-Ramírez et al. 2016 dissected the translocation events in the parasite periphery, showing that two successive translocation steps are needed for the export of transmembrane proteins, one at the PPM and one ...
The results described in this paper indicate that HIV unspliced RNA export and Gag trafficking to the plasma membrane are linked. By simply changing the RNA export element from the RRE to 4 × CTE, we can restore Gag assembly and budding in murine cells (Figures 3 and 5). To explain how a pretranslational event, RNA export, could modulate a post‐translational event, membrane trafficking, we hypothesize that HIV RNA is marked at (or by) nuclear export such that the cytosolic fate of the encoded Gag is predetermined. Based on our findings, both the RRE/Rev/Crm1 and 4 × CTE/NXF1 nuclear export pathways successfully mark unspliced gag‐pol mRNA in human cells and promote proper assembly. However, in murine cells, marking through the action of RRE/Rev/Crm1 is defective and HIV assembly is inhibited. Possibilities for the mark include the structure of the mRNA itself or proteins that comprise the mRNP; these could be added or removed as the export complex is formed, as it transits the NPC, ...
Normal numbers of salivary gland sporozoites are produced. Sporozoites showed reduced gliding motility and cell traversal capacity in vitro. Invasion of HepG2 cells in vitro was comparable to that of wild type parasites. Infectivity of sporozoites to mice was strongly reduced (as tested by intravenous injection of purified sporozoites or after infection of mice by mosquito bite). Salivary gland sporozoites show premature development into early liver stage forms (see further Additional remarks phenotype ...
HOPKINTON, Mass., Jan. 8, 2013 /PRNewswire/ -- EMC Helps Leading Vaccine Manufacturer Boost IT Efficiency; Reduces TCO 20% with Life Sciences Solution....
PPLP2 localization in asexual blood stage parasites. PPLP2-positive vesicular structures are present in the cytoplasm of trophozoites (TZ) and schizonts (SZ). PPLP2 was immunolabelled with mouse anti-PPLP2RP1 antisera (green), the asexual blood stages were visualized by rabbit anti-MSP1 antisera (red). Nuclei were highlighted by Hoechst stain (blue). PPLP2 first appeared in the trophozoites stage and here localized in vesicular structures. Multiple PPLP2-positive vesicular structures were detected also in mature schizonts. The blood stage parasites were highlighted by labelling of MSP1.Wirth CC, Glushakova S, Scheuermayer M, Repnik U, Garg S, Schaack D, Kachman MM, Weißbach T, Zimmerberg J, Dandekar T, Griffiths G, Chitnis CE, Singh S, Fischer R, Pradel G. Perforin-like protein PPLP2 permeabilizes the red blood cell membrane during egress of Plasmodium falciparum gametocytes. Cell Microbiol. 2014 Mar 7.. See original on MMP ...
Author Summary The phylum Apicomplexa includes a number of medically and agriculturally relevant parasites. These include the Plasmodium species, agents of malaria and estimated to cause over 1 million deaths per year, and Toxoplasma gondii, which infects 30-80% of any human population. These parasites rely on a unique form of actomyosin-powered motility to perpetuate infection, but the molecular mechanisms regulating this vital process are virtually unknown. Here, we describe a plant-like Ca2+-dependent kinase of T. gondii, TgCDPK3, which is involved in the rapid activation of egress from host cells during Ca2+ signaling. T. gondiis requirement for TgCDPK3 seems to rely specifically on the local ionic environment, being dispensable in conditions typical of the extracellular environment. Activity is also dependent on localization to the parasite plasma membrane, which appears to be conferred by a consensus motif at the kinase N-terminus that is typically acylated. This work provides some of the first
Among 1521 microscopically positive P. falciparum samples screened, 50 were negative by HRP2 based RDT test. Molecular testing was carried out using these 50 RDT negative samples by assuming that 1471 RDT positive samples carried pfhrp2 gene. It was found that 2.4% (36/1521) and 1.8% (27/1521) of samples were negative for pfhrp2 and pfhrp3 genes, respectively. However, the frequency of pfhrp2 deletions varied between the sites ranging from 0-25% (2.4, 95% CI; 1.6-3.3). The frequency of both pfhrp2 and pfhrp3 gene deletion varied from 0-8% (1.6, 95% CI; 1.0-2.4 ...
Abstract. The magnitude of antibody responses varies across the individual proteins that constitute any given microorganism, both in the context of natural infection and vaccination with attenuated or inactivated pathogens. The protein-specific factors underlying this variability are poorly understood. In 267 individuals exposed to intense seasonal malaria, we examined the relationship between immunoglobulin G (IgG) responses to 861 Plasmodium falciparum proteins and specific features of these proteins, including their subcellular location, relative abundance, degree of polymorphism, and whether they are predicted to have human orthologs. We found that IgG reactivity was significantly higher to extracellular and plasma membrane proteins and also correlated positively with both protein abundance and degree of protein polymorphism. Conversely, IgG reactivity was significantly lower to proteins predicted to have human orthologs. These findings provide insight into protein-specific factors that are
Plasmodium falciparum võib osadel inimestel osade emaste hallasääskede vereimemise (toidukorra) ajal süljepiiskadega ühelt inimeselt teisele kanduda ja Plasmodium falciparum-malaariat põhjustada. Enne ülekannet asub Plasmodium falciparum nakatunud emaste sääskede süljenäärmetes - sporozoiidi staadiumis. Sääse vereimemise (vereeine) ajal püüab ta pistekohta pisut sülge pritsida, sülg sisaldab verejooksu tõkestavaid ja põletikuvastaseid ensüüme, mis takistavad vere hüübimist ja püüavad valu vaigistada. Pikka aega arvati ,et sääsepiste võib sisaldada 5-200 sporozoiiti, mis pääsevad inimese vereringesse - ringlevad mõne minuti ja jõuavad hepatotsüütidesse. Hiljutised uuringud aga näitavad, et moskiito saadab plasmoodumi sporozoiidid naha sisse, kus need võivad olla ligi 6 tundi ja ligi 1/3 neist kes lahkuvad pistekohast sisenevadlümfiringesse ja pääsevad kohalikesse lümfisõlmedesse, teised aga liigutavad end ussitaoliselt vereringesse ja liiguvad ka ...
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Growth of the intraerythrocytic malaria parasite is accompanied by an intense period of membrane biogenesis including production of a vacuolar system that surrounds and supports the parasites expansion in the host cell (Vial et al., 1990). The processes of membrane engineering that underlie this biogenesis begin with parasite invasion of the erythrocyte and continue with development of the surrounding PVM, TVN extensions into the host cell cytoplasm, MC and small vesicles that may move between some of these structures and the host membrane (Aikawa, 1988; Taraschi et al., 2003; Bhattacharjee et al., 2008; Hanssen et al., 2008; Kilian et al., 2013).. The human erythrocyte, although a naturally non-endocytic cell, is induced by the malaria merozoite to invaginate for incorporation of the young parasite into the sealed PVM (Miller et al., 1979). A number of studies have found that the newly formed PVM includes host membrane lipids that flow past the erythrocyte-merozoite moving junction and leave ...
They will also explain our admissions process and discuss financial aid options. Do you have no idea what to do with them? Other literature review of plasmodium falciparum , Projects , Activities. The student support team offers counselling, disability services, learning support and Indigenous student support. Yvonne Blomer, Shannon Webb-Campbell, and the other authors of the twenty-three essays in this collection, have layered and woven the personal with the public, and candid honesty with literature review of plasmodium falciparum pertinent details so we get a real sense of who the writer is in that particular place. Define the problem Analyze the problem Define the problem in the scenario that you have chosen Answered by JesseCraig. We publish articles highlighting science news on campus as well as groundbreaking research across the world. Im 16, and mature for my age. In my classroom, students are expected to get their notebooks from their bin, sit down at their desk, and begin work on ...
In this study we performed light, immunofluorescent and transmission electron microscopy of Colpodella trophozoites to characterize trophozoite morphology and protein distribution. The use of Giemsa staining and antibodies to distinguish Colpodella life cycle stages has not been performed previously. Rhoptry and β-tubulin antibodies were used in immunofluorescent assays (IFA) to identify protein localization and distribution in the trophozoite stage of Colpodella (ATCC 50594). We report novel data identifying "doughnut-shaped" vesicles in the cytoplasm and apical end of Colpodella trophozoites reactive with antibodies specific to Plasmodium merozoite rhoptry proteins. Giemsa staining and immunofluorescent microscopy identified different developmental stages of Colpodella trophozoites, with the presence or absence of vesicles corresponding to maturity of the trophozoite. These data demonstrate for the first time evidence of rhoptry protein conservation between Plasmodium and Colpodella and ...
The duration of Plasmodium falciparum infections. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
A model is developed and used to study within-human malaria parasite dynamics. The model integrates actors involved in the development-progression of parasitemia, gametocytogenesis and mechanisms for...
Dean S, Moreira-Leite F, Gull K (2019). Basalin is an evolutionarily unconstrained protein revealed via a conserved role in flagellum basal plate function. eLife 8: e42282. 10.7554/eLife.42282. Sunter JD, Yanase R, Wang Z, Catta-Preta CMC, Moreira-Leite F, Myskova J, Pruzinova K, Volf P, Mottram JC, Gull K (2019). Leishmania flagellum attachment zone is critical for flagellar pocket shape, development in the sand fly, and pathogenicity in the host. PNAS 116:6351-6360. 10.1073/pnas.1812462116.. Sunter JD, Moreira-Leite F, Gull K. (2018). Dependency relationships between IFT-dependent flagellum elongation and cell morphogenesis in Leishmania. Open Biol 8:180124. 10.1098/rsob.180124.. Edwards BFL, Wheeler RJ, Barker AR, Moreira-Leite FF, Gull K, Sunter JD (2018). Direction of flagellum beat propagation is controlled by proximal/distal outer dynein arm asymmetry. PNAS 115:E7341-E7350. 10.1073/pnas.1805827115. Varga V, Moreira-Leite F, Portman N, Gull K (2017). Protein diversity in discrete ...
A monoclonal antibody-based immunoassay to measure the antibody response against the repeat region of the circumsporozoite protein of Plasmodium falciparum ...
We investigated if any var types were shared between the three patients. This was not expected as previous studies have shown minimal overlap in the expressed var repertoire between patients (Kaestli et al., 2004; Bull et al., 2005; Kyriacou et al., 2006). There was only one var type shared between PM55 and PM32, detected at two copies in the heart of PM55 and in all four organs of PM32. There were no var types shared between PM30 and PM55. Surprisingly, there was substantial overlap in the var types detected in PM30 and PM32, with 20 DBLα/var types detected in both cases (Fig. 1). These sequences were identical between the two patients. It is important to note that shared DBLα sequence does not necessarily imply that that entire var genes represented by each tag are identical. However, we will continue to refer to these as var types for continuity.. The shared var types accounted for 20% of PM30 var types and 26% of PM32 var types, compromising 61% and 32% of all clones detected in each ...
HRP偶联Plasmodium falciparum抗体[MPFG-55P](ab30384)经WB, ELISA, sELISA实验严格验证,被1篇文献引用,实验条件参看说明书。中国75%以上现货。
Diversity in the MSP-1 gene of Plasmodium falciparum. In A, conserved, semiconserved and variable blocks of the MSP-1 gene are represented as open, hatched and
(2010) Cristodero et al. Molecular Microbiology. The parasitic protozoa Trypanosoma brucei has a complex life cycle. Oxidative phosphorylation is highly active in the procyclic form but absent from bloodstream cells. The mitochondrial genome enco...
Plasmodium falciparum GR2 protein: maintains high levels of reduced reductase in the cytosol; amino acid sequence in first source; GenBank X93462
BioAssay record AID 743346 submitted by NCGC: qHTS profiling of the MIPE4 collection as inhibitors of Plasmodium falciparum (DD2) proliferation (Rep 2).
BioAssay record AID 743345 submitted by NCGC: qHTS profiling of the MIPE4 collection as inhibitors of Plasmodium falciparum (DD2) proliferation.
Sharma, SK (2004) Characterization and inhibition of Plasmodium falciparum beta-hydroxyacyl-ACP dehydratase (PfFabZ): A potential antimalarial target. In: 18th Symposium of the Protein-Society, AUG 14-18, 2004, San Diego, CA. Full text not available from this repository ...
Created after (Sernee et al., Cell Host & Microbe, 2019), in press [PMID=31513773]. The dual activity mannosyltransferases/phosphorylases of six Leishmania proteins allows the management of mannogen (storage polysacharride). Family evolutionary related the bacterial GH130 phosphorylases ...
From a minimal and simplified viewpoint, life is a succession of events leading to transmission of genes from parents to offspring. For certain organisms, like protozoan parasites, these events must include a meeting with someone else: another eukaryote to act as an invertebrate or vertebrate host and occasionally a human host. To get a successful gene transmission, parasites must have a positive outcome of the infection event (or series of events, as the infection for some parasites means a complex cycle between two or more hosts). But infection does not represent a one way event: it is a disruptive phenomenon, by which the metabolic balance of one organism is perturbed in favour of the survival and gene dissemination of another one, the intruder. It is thus a two sided event that implies several biochemical and immunological defense mechanisms being mounted by the host, and molecular barriers which need to be past by the parasite. If left without human intervention, this interaction would ...
Gene-by-gene comparison of expression levels for mixed asexual versus sporozoite stages and mixed asexual parasites versus heat shock treated mixed asexual para
Protective Efficacy)P. falciparum blood stage infection defined asdetection of at least 2 P. falciparum parasites by microscopic examination of 0.5 L starting immediately following PfSPZ CHMI (Arms 1c, 1d) [PILOT STUDY ...
Websters defines parasites as the scariest things on earth, that threaten our very way of life. Or at least thats how they should define them. Parasites are utterly frightening and the effect they have on their hosts does not tend to be pleasant. Some of them out there are truly ...
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