Babesiosis, caused by protozoan parasites of the genus , is an emerging tick-borne disease of significance for both human and animal health. parasites infect erythrocytes of vertebrate hosts where they develop and multiply rapidly to cause the pathological symptoms associated with the disease. The identification of new species underscores the ongoing risk of zoonotic pathogens capable of infecting humans, a concern amplified by anthropogenic activities and environmental changes.
View Article and Find Full Text PDFPolyamines are polycationic molecules that are crucial in a wide array of cellular functions. Their biosynthesis is mediated by aminopropyl transferases (APTs), promising targets in antimicrobial, antineoplastic and antineurodegenerative therapies. A major limitation, however, is the lack of high-throughput assays to measure their activity.
View Article and Find Full Text PDFHuman babesiosis is a potentially fatal tick-borne disease caused by intraerythrocytic Babesia parasites. The emergence of resistance to recommended therapies highlights the need for new and more effective treatments. Here we demonstrate that the 8-aminoquinoline antimalarial drug tafenoquine inhibits the growth of different Babesia species in vitro, is highly effective against Babesia microti and Babesia duncani in mice and protects animals from lethal infection caused by atovaquone-sensitive and -resistant B.
View Article and Find Full Text PDFBabesiosis is a malaria-like disease in humans and animals that is caused by Babesia species, which are tick-transmitted apicomplexan pathogens. Babesia duncani causes severe to lethal infection in humans, but despite the risk that this parasite poses as an emerging pathogen, little is known about its biology, metabolic requirements or pathogenesis. Unlike other apicomplexan parasites that infect red blood cells, B.
View Article and Find Full Text PDFBabesiosis is a tick-borne disease caused by pathogens belonging to the genus Babesia. In humans, the disease presents as a malaria-like illness and can be fatal in immunocompromised and elderly people. In the past few years, human babesiosis has been a rising concern worldwide.
View Article and Find Full Text PDFFront Cell Infect Microbiol
December 2022
The significant rise in the number of tick-borne diseases represents a major threat to public health worldwide. One such emerging disease is human babesiosis, which is caused by several protozoan parasites of the genus of which is responsible for most clinical cases reported to date. Recent studies have shown that during its intraerythrocytic life cycle, exports several antigens into the mammalian host using a novel vesicular-mediated secretion mechanism.
View Article and Find Full Text PDFContinuous propagation of in vitro in human erythrocytes and the availability of a mouse model of lethal infection make this parasite an ideal model to study biology and pathogenesis. Two culture media, HL-1 and Claycomb, with proprietary formulations are the only culture media known to support the parasite growth in human erythrocytes; however, the HL-1 medium has been discontinued and the Claycomb medium is often unavailable leading to major interruptions in the study of this pathogen. To identify alternative media conditions, we evaluated the growth of in various culture media with well-defined compositions.
View Article and Find Full Text PDFBackground: SARS-CoV-2 infection has, as of April 2021, affected >133 million people worldwide, causing >2.5 million deaths. Because the large majority of individuals infected with SARS-CoV-2 are asymptomatic, major concerns have been raised about possible long-term consequences of the infection.
View Article and Find Full Text PDFAn effective strategy to control blood-borne diseases and prevent outbreak recrudescence involves targeting conserved metabolic processes that are essential for pathogen viability. One such target for and , the infectious agents of malaria and babesiosis, respectively, is the mitochondrial cytochrome protein complex, which can be inhibited by endochin-like quinolones (ELQ) and atovaquone. We used the tick-transmitted and culturable blood-borne pathogen to evaluate the structure-activity relationship, safety, efficacy, and mode of action of ELQs.
View Article and Find Full Text PDFExtracellular vesicles are thought to facilitate pathogen transmission from arthropods to humans and other animals. Here, we reveal that pathogen spreading from arthropods to the mammalian host is multifaceted. Extracellular vesicles from Ixodes scapularis enable tick feeding and promote infection of the mildly virulent rickettsial agent Anaplasma phagocytophilum through the SNARE proteins Vamp33 and Synaptobrevin 2 and dendritic epidermal T cells.
View Article and Find Full Text PDFThe examination of the complex cell biology of the human malaria parasite Plasmodium falciparum usually relies on the time-consuming generation of transgenic parasites. Here, metabolic labeling and click chemistry are employed as a fast transfection-independent method for the microscopic examination of protein S-palmitoylation, an important post-translational modification during the asexual intraerythrocytic replication of P. falciparum.
View Article and Find Full Text PDFThe tick- and transfusion-transmitted human pathogen infects host erythrocytes to cause the pathologic symptoms associated with human babesiosis, an emerging disease with worldwide distribution and potentially fatal clinical outcome. Drugs currently recommended for the treatment of babesiosis are associated with a high failure rate and significant adverse events, highlighting the urgent need for more-effective and safer babesiosis therapies. Unlike other apicomplexan parasites, lacks a canonical lactate dehydrogenase (LDH) but instead expresses a unique enzyme, LDH (BmLDH), acquired through evolution by horizontal transfer from a mammalian host.
View Article and Find Full Text PDFRabbit coccidiosis is a common parasitic disease and responsible for enormous economic losses in the rabbit industry. Eimeria intestinalis, one of the highly pathogenic and common Eimeria species infecting rabbits, is considered as an indispensable species for the development of live oocyst vaccines against rabbit coccidiosis. In this study, we report the successful selection of a precocious line (EIP8) from a wild-type strain of E.
View Article and Find Full Text PDFEimeria spp., the causative agents of coccidiosis, are the most common protozoan pathogens of chickens. Infection with these parasites can result in poor development or death of animals leading to a devastating economic impact on poultry production.
View Article and Find Full Text PDFBabesia microti and Babesia duncani are the main causative agents of human babesiosis in the United States. While significant knowledge about B. microti has been gained over the past few years, nothing is known about B.
View Article and Find Full Text PDFPiroplasmid parasites comprising of , , and are transmitted by ticks to farm and pet animals and have a significant impact on livestock industries and animal health in tropical and subtropical regions worldwide. In addition, diverse spp. infect humans as opportunistic hosts.
View Article and Find Full Text PDFBackground: Plasmodium falciparum malaria is one of the most widespread parasitic infections in humans and remains a leading global health concern. Malaria elimination efforts are threatened by the emergence and spread of resistance to artemisinin-based combination therapy, the first-line treatment of malaria. Promising molecular markers and pathways associated with artemisinin drug resistance have been identified, but the underlying molecular mechanisms of resistance remains unknown.
View Article and Find Full Text PDFThe biosynthesis of the major acyl carrier Coenzyme A from pantothenic acid (PA) is critical for survival of Plasmodium falciparum within human erythrocytes. Accordingly, a PA analog α-PanAm showed potent activity against blood stage parasites in vitro; however, its efficacy in vivo and its mode of action remain unknown. We developed a new synthesis route for α-PanAm and showed that the compound is highly effective against blood stages of drug-sensitive and -resistant P.
View Article and Find Full Text PDFBackground: Babesia microti is an emerging tick-borne apicomplexan parasite with increasing geographic range and incidence in the United States. The rapid expansion of B. microti into its current distribution in the northeastern USA has been due to the range expansion of the tick vector, Ixodes scapularis, upon which the causative agent is dependent for transmission to humans.
View Article and Find Full Text PDFBabesia microti is the primary causative agent of human babesiosis, an emerging pathogen that causes a malaria-like illness with possible fatal outcome in immunocompromised patients. The genome sequence of the B. microti R1 strain was reported in 2012 and revealed a distinct evolutionary path for this pathogen relative to that of other apicomplexa.
View Article and Find Full Text PDFPhosphoethanolamine methyltransferases (PMTs also known as PEAMTs) catalyze the three-step s-adenosyl-methionione-dependent methylation of phosphoethanolamine to form phosphocholine. These enzymes play an important function in the synthesis of phosphatidylcholine, the major phospholipid in the membranes of lower and higher eukaryotes, as well as in the production of the compatible solute and osmoprotectant glycine betaine in plants. Genetic studies in plants, Caenhorhabditis elegans and Plasmodium falciparum have demonstrated that disruption of PMT activity results in severe defects in important cellular processes such as development, replication, survival and sexual maturation and differentiation.
View Article and Find Full Text PDFThe 23-megabase genome of Plasmodium falciparum, the causative agent of severe human malaria, contains ∼5300 genes, most of unknown function or lacking homologs in other organisms. Identification of these gene functions will help in the discovery of novel targets for the development of antimalarial drugs and vaccines. The P.
View Article and Find Full Text PDFCyclin-dependent kinases (CDKs) have an established role in metazoans and yeast in DNA replication, transcription and cell cycle regulation. Several CDKs and their effectors have been identified in the malaria parasite Plasmodium falciparum and their biological functions are beginning to be investigated. Here we report results from the functional characterization of Pfmrk and its effector PfMAT1.
View Article and Find Full Text PDFRepeated immunizations with whole Plasmodium blood stage parasites and concomitant drug cure of infection confer protective immunity against parasite challenge in mice, monkeys and humans. Moreover, it was recently shown that infections with genetically modified rodent malaria blood stage parasites conferred sterile protection against lethal blood stage challenge. However, in these models vaccination resulted in high parasitemias and, in consequence, carries risk of vaccine-induced pathology and death.
View Article and Find Full Text PDFBackground: The phosphoethanolamine methyltransferase, PfPMT, of the human malaria parasite Plasmodium falciparum, a member of a newly identified family of phosphoethanolamine methyltransferases (PMT) found solely in some protozoa, nematodes, frogs, and plants, is involved in the synthesis of the major membrane phospholipid, phosphatidylcholine. PMT enzymes catalyze a three-step S-adenosylmethionine-dependent methylation of the nitrogen atom of phosphoethanolamine to form phosphocholine. In P.
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