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1.
BMC Genomics ; 25(1): 196, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373902

RESUMO

Lumpy skin disease virus (LSDV) belongs to the genus Capripoxvirus and family Poxviridae. LSDV was endemic in most of Africa, the Middle East and Turkey, but since 2015, several outbreaks have been reported in other countries. In this study, we used whole genome sequencing approach to investigate the origin of the outbreak and understand the genomic landscape of the virus. Our study showed that the LSDV strain of 2022 outbreak exhibited many genetic variations compared to the Reference Neethling strain sequence and the previous field strains. A total of 1819 variations were found in 22 genome sequences, which includes 399 extragenic mutations, 153 insertion frameshift mutations, 234 deletion frameshift mutations, 271 Single nucleotide polymorphisms (SNPs) and 762 silent SNPs. Thirty-eight genes have more than 2 variations per gene, and these genes belong to viral-core proteins, viral binding proteins, replication, and RNA polymerase proteins. We highlight the importance of several SNPs in various genes, which may play an essential role in the pathogenesis of LSDV. Phylogenetic analysis performed on all whole genome sequences of LSDV showed two types of variants in India. One group of the variant with fewer mutations was found to lie closer to the LSDV 2019 strain from Ranchi while the other group clustered with previous Russian outbreaks from 2015. Our study highlights the importance of genomic characterization of viral outbreaks to not only monitor the frequency of mutations but also address its role in pathogenesis of LSDV as the outbreak continues.


Assuntos
Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Animais , Bovinos , Vírus da Doença Nodular Cutânea/genética , Doença Nodular Cutânea/epidemiologia , Doença Nodular Cutânea/genética , Filogenia , Genômica , Surtos de Doenças
2.
Proteomics ; 21(20): e2100004, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34558204

RESUMO

All eukaryotic flagella are made of microtubules and driven by dynein motor proteins. However, every organism is unique in terms of its flagellar waveform, beat frequency, and its general motility pattern. With recent research, it is becoming clear that despite overall conservation in flagellar structure, the pattern of tubulin post-translational modifications within the flagella are diverse and may contribute to variations in their patterns of motility. In this study, we have analyzed the tubulin post-translational modification in the protozoan parasites Giardia lamblia and Trichomonas vaginalis using global, untargeted mass spectrometry. We show that tubulin monoglycylation is a modification localized to the flagella present in G. lamblia but absent in T. vaginalis. We also show the presence of glutamylated tubulin in both G. lamblia and T. vaginalis. Using MS/MS, we were also able to identify the previously unknown sites of monoglycylation in ß-tubulin at E438 and E439 in G. lamblia. Using isolated flagella, we also characterized the flagellar proteome in G. lamblia and T. vaginalis and identified 475 proteins in G. lamblia and 386 proteins in T. vaginalis flagella. Altogether, the flagellar proteomes as well as the sites of tubulin PTMs in these organisms, reveal potential mechanisms in regulating flagellar motilities in these neglected protozoan parasites.


Assuntos
Giardia lamblia , Trichomonas vaginalis , Flagelos/metabolismo , Giardia lamblia/metabolismo , Processamento de Proteína Pós-Traducional , Proteômica , Espectrometria de Massas em Tandem , Trichomonas vaginalis/metabolismo , Tubulina (Proteína)
3.
J Proteome Res ; 20(3): 1591-1601, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33555895

RESUMO

A novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19) and continues to be a global health challenge. To understand viral disease biology, we have carried out proteo-genomic analysis using next-generation sequencing (NGS) and mass spectrometry on nasopharyngeal swabs of COVID-19 patients to examine the clinical genome and proteome. Our study confirms the mutability of SARS-CoV-2 showing multiple single-nucleotide polymorphisms. NGS analysis detected 27 mutations, of which 14 are synonymous, 11 are missense, and 2 are extragenic in nature. Phylogenetic analysis of SARS-CoV-2 isolates indicated their close relation to a Bangladesh isolate and multiple origins of isolates within the country. Our proteomic analysis, for the first time, identified 13 different SARS-CoV-2 proteins from the clinical swabs. Of the total 41 peptides captured by high-resolution mass spectrometry, 8 matched to nucleocapsid protein, 2 to ORF9b, and 1 to spike glycoprotein and ORF3a, with remaining peptides mapping to ORF1ab polyprotein. Additionally, host proteome analysis revealed several key host proteins to be uniquely expressed in COVID-19 patients. Pathway analysis of these proteins points toward modulation in immune response, especially involving neutrophil and IL-12-mediated signaling. Besides revealing the aspects of host-virus pathogenesis, our study opens new avenues to develop better diagnostic markers and therapeutic approaches.


Assuntos
COVID-19/virologia , Polimorfismo de Nucleotídeo Único , SARS-CoV-2/genética , Proteínas do Nucleocapsídeo de Coronavírus/genética , Genoma Viral , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Mutação , Pandemias , Fosfoproteínas/genética , Filogenia , Poliproteínas/genética , Proteoma , Proteômica , SARS-CoV-2/patogenicidade , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/genética , Proteínas Virais/genética , Proteínas Viroporinas/genética
4.
Cell Microbiol ; 19(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27649068

RESUMO

HSP90 chaperones are essential regulators of cellular function, as they ensure the appropriate conformation of multiple key client proteins. Four HSP90 isoforms were identified in the protozoan parasite Theileria annulata. Partial characterization was undertaken for three and localization confirmed for cytoplasmic (TA12105), endoplasmic reticulum (TA06470), and apicoplast (TA10720) forms. ATPase activity and binding to the HSP90 inhibitor geldanamycin were demonstrated for recombinant TA12105, and all three native forms could be isolated to varying extents by binding to geldanamycin beads. Because it is essential, HSP90 is considered a potential therapeutic drug target. Resistance to the only specific Theileriacidal drug is increasing, and one challenge for design of drugs that target the parasite is to limit the effect on the host. An in vitro cell culture system that allows comparison between uninfected bovine cells and the T. annulata-infected counterpart was utilized to test the effects of geldanamycin and the derivative 17-AAG. T. annulata-infected cells had greater tolerance to geldanamycin than uninfected cells yet exhibited significantly more sensitivity to 17-AAG. These findings suggest that parasite HSP90 isoform(s) can alter the drug sensitivity of infected host cells and that members of the Theileria HSP90 family are potential targets worthy of further investigation.


Assuntos
Proteínas de Choque Térmico HSP90/análise , Leucócitos/parasitologia , Organelas/enzimologia , Isoformas de Proteínas/análise , Theileria annulata/enzimologia , Animais , Bovinos , Células Cultivadas
5.
Parasitology ; 145(13): 1772-1782, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30008275

RESUMO

Malaria is the major cause of mortality and morbidity in tropical countries. The causative agent, Plasmodium sp., has a complex life cycle and is armed with various mechanisms which ensure its continuous transmission. Gametocytes represent the sexual stage of the parasite and are indispensable for the transmission of the parasite from the human host to the mosquito. Despite its vital role in the parasite's success, it is the least understood stage in the parasite's life cycle. The presence of gametocytes in asymptomatic populations and induction of gametocytogenesis by most antimalarial drugs warrants further investigation into its biology. With a renewed focus on malaria elimination and advent of modern technology available to biologists today, the field of gametocyte biology has developed swiftly, providing crucial insights into the molecular mechanisms driving sexual commitment. This review will summarise key current findings in the field of gametocyte biology and address the associated challenges faced in malaria detection, control and elimination.


Assuntos
Culicidae/parasitologia , Estágios do Ciclo de Vida , Malária/transmissão , Plasmodium/fisiologia , Animais , Antimaláricos/farmacologia , Infecções Assintomáticas , Humanos , Malária/parasitologia , Plasmodium/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/fisiologia
6.
J Biol Chem ; 289(24): 16662-74, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24755215

RESUMO

The malaria parasite experiences a significant amount of redox stress during its growth in human erythrocytes and heavily relies on secretory functions for pathogenesis. Most certainly, the parasite is equipped with machinery to tackle perturbations in the secretory pathway, like the unfolded protein response pathway in higher eukaryotes. Our bioinformatics analysis revealed the complete absence of genes involved in the canonical unfolded protein response pathway in Plasmodium falciparum. Accordingly, the parasite was unable to up-regulate endoplasmic reticulum (ER) chaperones or ER-associated degradation in response to DTT-mediated ER stress. Global profiling of gene expression upon DTT treatment revealed a network of AP2 transcription factors and their targets being activated. The overall outcome was up-regulation of genes involved in protein export and the sexual stage of the parasite life cycle culminating in gametocytogenesis. Our results suggest that the malaria parasite uses ER stress as a cue to switch to the transmissible sexual stages.


Assuntos
Estresse do Retículo Endoplasmático , Gametogênese/genética , Plasmodium falciparum/genética , Resposta a Proteínas não Dobradas/genética , Perfilação da Expressão Gênica , Genes de Protozoários , Células HeLa , Humanos , Células Jurkat , Estágios do Ciclo de Vida , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Fator de Transcrição AP-2/genética , Fator de Transcrição AP-2/metabolismo , Regulação para Cima
7.
BMC Genomics ; 16: 686, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26346253

RESUMO

BACKGROUND: Candida auris is a multidrug resistant, emerging agent of fungemia in humans. Its actual global distribution remains obscure as the current commercial methods of clinical diagnosis misidentify it as C. haemulonii. Here we report the first draft genome of C. auris to explore the genomic basis of virulence and unique differences that could be employed for differential diagnosis. RESULTS: More than 99.5 % of the C. auris genomic reads did not align to the current whole (or draft) genome sequences of Candida albicans, Candida lusitaniae, Candida glabrata and Saccharomyces cerevisiae; thereby indicating its divergence from the active Candida clade. The genome spans around 12.49 Mb with 8527 predicted genes. Functional annotation revealed that among the sequenced Candida species, it is closest to the hemiascomycete species Clavispora lusitaniae. Comparison with the well-studied species Candida albicans showed that it shares significant virulence attributes with other pathogenic Candida species such as oligopeptide transporters, mannosyl transfersases, secreted proteases and genes involved in biofilm formation. We also identified a plethora of transporters belonging to the ABC and major facilitator superfamily along with known MDR transcription factors which explained its high tolerance to antifungal drugs. CONCLUSIONS: Our study emphasizes an urgent need for accurate fungal screening methods such as PCR and electrophoretic karyotyping to ensure proper management of fungemia. Our work highlights the potential genetic mechanisms involved in virulence and pathogenicity of an important emerging human pathogen namely C. auris. Owing to its diversity at the genomic scale; we expect the genome sequence to be a useful resource to map species specific differences that will help develop accurate diagnostic markers and better drug targets.


Assuntos
Candida/efeitos dos fármacos , Candida/genética , Farmacorresistência Fúngica , Resistência a Múltiplos Medicamentos , Genoma Fúngico , Sequência de Aminoácidos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida/classificação , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Códon , Biologia Computacional/métodos , DNA Intergênico , Evolução Molecular , Loci Gênicos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fator de Acasalamento , Testes de Sensibilidade Microbiana , Anotação de Sequência Molecular , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Filogenia , Virulência/genética
8.
Antimicrob Agents Chemother ; 60(3): 1464-75, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26711771

RESUMO

Imidazopyridazine compounds are potent, ATP-competitive inhibitors of calcium-dependent protein kinase 1 (CDPK1) and of Plasmodium falciparum parasite growth in vitro. Here, we show that these compounds can be divided into two classes depending on the nature of the aromatic linker between the core and the R2 substituent group. Class 1 compounds have a pyrimidine linker and inhibit parasite growth at late schizogony, whereas class 2 compounds have a nonpyrimidine linker and inhibit growth in the trophozoite stage, indicating different modes of action for the two classes. The compounds also inhibited cyclic GMP (cGMP)-dependent protein kinase (PKG), and their potency against this enzyme was greatly reduced by substitution of the enzyme's gatekeeper residue at the ATP binding site. The effectiveness of the class 1 compounds against a parasite line expressing the modified PKG was also substantially reduced, suggesting that these compounds kill the parasite primarily through inhibition of PKG rather than CDPK1. HSP90 was identified as a binding partner of class 2 compounds, and a representative compound bound to the ATP binding site in the N-terminal domain of HSP90. Reducing the size of the gatekeeper residue of CDPK1 enabled inhibition of the enzyme by bumped kinase inhibitors; however, a parasite line expressing the modified enzyme showed no change in sensitivity to these compounds. Taken together, these findings suggest that CDPK1 may not be a suitable target for further inhibitor development and that the primary mechanism through which the imidazopyridazines kill parasites is by inhibition of PKG or HSP90.


Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Antimaláricos/química , Linhagem Celular , Proteínas Quinases Dependentes de GMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Imidazóis/química , Imidazóis/farmacologia , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular/métodos , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Piridazinas/química , Piridazinas/farmacologia
9.
Malar J ; 13: 118, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24674379

RESUMO

BACKGROUND: Heat shock factor binding protein (HSBP) was originally discovered in a yeast two-hybrid screen as an interacting partner of heat shock factor (HSF). It appears to be conserved in all eukaryotes studied so far, with yeast being the only exception. Cell biological analysis of HSBP in mammals suggests its role as a negative regulator of heat shock response as it appears to interact with HSF only during the recovery phase following exposure to heat stress. While the identification of HSF in the malaria parasite is still eluding biologists, this study for the first time, reports the presence of a homologue of HSBP in Plasmodium falciparum. METHODS: PfHSBP was cloned and purified as his-tag fusion protein. CD (Circular dichroism) spectroscopy was performed to predict the secondary structure. Immunoblots and immunofluorescence approaches were used to study expression and localization of HSBP in P. falciparum. Cellular fractionation was performed to examine subcellular distribution of PfHSBP. Immunoprecipitation was carried out to identify HSBP interacting partner in P. falciparum. RESULTS: PfHSBP is a conserved protein with a high helical content and has a propensity to form homo-oligomers. PfHSBP was cloned, expressed and purified. The in vivo protein expression profile shows maximal expression in trophozoites. The protein was found to exist in oligomeric form as trimer and hexamer. PfHSBP is predominantly localized in the parasite cytosol, however, upon heat shock, it translocates to the nucleus. This study also reports the interaction of PfHSBP with PfHSP70-1 in the cytoplasm of the parasite. CONCLUSIONS: This study emphasizes the structural and biochemical conservation of PfHSBP with its mammalian counterpart and highlights its potential role in regulation of heat shock response in the malaria parasite. Analysis of HSBP may be an important step towards identification of the transcription factor regulating the heat shock response in P. falciparum.


Assuntos
Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico , Plasmodium falciparum/fisiologia , Sequência de Aminoácidos , Núcleo Celular/metabolismo , Citosol/metabolismo , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Dados de Sequência Molecular , Plasmodium falciparum/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Alinhamento de Sequência
10.
Parasitology ; 141(9): 1148-55, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24912527

RESUMO

Trypanosomiasis is caused by Trypanosoma species which affect both human and animal populations and pose a major threat to developing countries. The incidence of animal trypanosomiasis is on the rise. Surra is a type of animal trypanosomiasis, caused by Trypanosoma evansi, and has been included in priority list B of significant diseases by the World Organization of Animal Health (OIE). Control of surra has been a challenge due to the lack of effective drugs and vaccines and emergence of resistance towards existing drugs. Our laboratory has previously implicated Heat shock protein 90 (Hsp90) from protozoan parasites as a potential drug target and successfully demonstrated efficacy of an Hsp90 inhibitor in cell culture as well as a pre-clinical mouse model of trypanosomiasis. This article explores the role of Hsp90 in the Trypanosoma life cycle and its potential as a drug target. It appears plausible that the repertoire of Hsp90 inhibitors available in academia and industry may have value for treatment of surra and other animal trypanosomiasis.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Tripanossomíase/tratamento farmacológico , Animais , Humanos , Camundongos , Estrutura Molecular , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Tripanossomicidas/química , Trypanosoma/metabolismo
11.
J Mol Biol ; 436(4): 168440, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38218367

RESUMO

Giardia lambliacauses giardiasis, one of the most common human infectious diseases globally. Previous studies from our lab have shown that hsp90 gene ofGiardia is split into two halves, namely hspN and hspC. The independent pre-mRNAs of these split genes join by trans-splicing, producing a full-length Hsp90 (FlHsp90) mRNA. Genetic manipulation of the participating genes is necessary to understand the mechanism and significance of such trans-splicing based expression of Hsp90. In this study, we have performed transfection based exogenous expression of hspN and/or hspC in G. lamblia. We electroporated a plasmid containing the Avi-tagged hspN component of Hsp90 and examined its fate in G. lamblia. We show that the exogenously expressed hspN RNA gets trans-spliced to endogenously expressed hspC RNA, giving rise to a hybrid-FlHsp90. We highlight the importance of cis-elements in this trans-splicing reaction through mutational analysis. The episomal plasmid carrying deletions in the intronic region of hspN, showed inhibition of the trans-splicing reaction.Additionally, exogenous hspC RNA also followed the same fate as of exogenous hspN, while upon co-transfection with episomal hspN, they underwent trans-splicing with each other. Using eGFP as a test protein, we have shown that intronic sequences of hsp90 gene can guide trans-splicing mediated repair of any associated exonic sequences. Our study provides in vivo validation of Hsp90 trans-splicing, showing crucial role of cis-elements and importantly highlights the potential of hsp90 intronic sequences to function as a minimal splicing tool.


Assuntos
Giardia lamblia , Proteínas de Choque Térmico HSP90 , Proteínas de Protozoários , Trans-Splicing , Giardia lamblia/genética , Íntrons/genética , Precursores de RNA/genética , Trans-Splicing/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Protozoários/genética
12.
Microbiol Res ; 281: 127605, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38232495

RESUMO

Spermidine is a poly-cationic molecule belonging to the family of polyamines and is ubiquitously present in all organisms. Salmonella synthesizes, and harbours specialized transporters to import spermidine. A group of polyamines have been shown to assist in Salmonella Typhimurium's virulence and regulation of Salmonella pathogenicity Inslad 1 (SPI-1) genes and stress resistance; however, the mechanism remains elusive. The virulence trait of Salmonella depends on its ability to employ multiple surface structures to attach and adhere to the surface of the target cells before invasion and colonization of the host niche. Our study discovers the mechanism by which spermidine assists in the early stages of Salmonella pathogenesis. For the first time, we report that Salmonella Typhimurium regulates spermidine transport and biosynthesis processes in a mutually inclusive manner. Using a mouse model, we show that spermidine is critical for invasion into the murine Peyer's patches, which further validated our in vitro cell line observation. We show that spermidine controls the mRNA expression of fimbrial (fimA) and non-fimbrial adhesins (siiE, pagN) in Salmonella and thereby assists in attachment to host cell surfaces. Spermidine also regulated the motility through the expression of flagellin genes by enhancing the translation of sigma-28, which features an unusual start codon and a poor Shine-Dalgarno sequence. Besides regulating the formation of the adhesive structures, spermidine tunes the expression of the two-component system BarA/SirA to regulate SPI-1 encoded genes. Thus, our study unravels a novel regulatory mechanism by which spermidine exerts critical functions during Salmonella Typhimurium pathogenesis.


Assuntos
Salmonella typhimurium , Espermidina , Animais , Camundongos , Salmonella typhimurium/metabolismo , Espermidina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Flagelina/genética , Poliaminas/metabolismo , Regulação Bacteriana da Expressão Gênica
13.
Biochim Biophys Acta ; 1823(3): 707-11, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22198098

RESUMO

Significant advances have been made in our understanding of heat shock protein 90 (Hsp90) in terms of its structure, biochemical characteristics, post-translational modifications, interactomes, regulation and functions. In addition to yeast as a model several new systems have now been examined including flies, worms, plants as well as mammalian cells. This review discusses themes emerging out of studies reported on Hsp90 from infectious disease causing protozoa. A common theme of sensing and responding to host cell microenvironment emerges out of analysis of Hsp90 in Malaria, Trypanosmiasis as well as Leishmaniasis. In addition to their functional roles, the potential of Hsp90 from these infectious disease causing organisms to serve as drug targets and the current status of this drug development endeavor are discussed. Finally, a unique and the only known example of a split Hsp90 gene from another disease causing protozoan Giardia lamblia and its evolutionary significance are discussed. Clearly studies on Hsp90 from protozoan parasites promise to reveal important new paradigms in Hsp90 biology while exploring its potential as an anti-infective drug target. This article is part of a Special Issue entitled: Heat Shock Protein 90 (HSP90).


Assuntos
Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Parasitos/genética , Parasitos/metabolismo , Animais , Microambiente Celular , Humanos , Infecções por Protozoários/parasitologia
14.
Biol Cell ; 104(1): 34-47, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22188458

RESUMO

BACKGROUND INFORMATION: The pathology causing stages of the human malaria parasite Plasmodium falciparum reside within red blood cells that are devoid of any regulated transport system. The parasite, therefore, is entirely responsible for mediating vesicular transport within itself and in the infected erythrocyte cytoplasm, and it does so in part via its family of 11 Rab GTPases. Putative functions have been ascribed to Plasmodium Rabs due to their homology with Rabs of yeast, particularly with Saccharomyces that has an equivalent number of rab/ypt genes and where analyses of Ypt function is well characterized. RESULTS: Rabs are important regulators of vesicular traffic due to their capacity to recruit specific effectors. In order to identify P. falciparum Rab (PfRab) effectors, we first built a Ypt-interactome by exploiting genetic and physical binding data available at the Saccharomyces genome database (SGD). We then constructed a PfRab-interactome using putative parasite Rab-effectors identified by homology to Ypt-effectors. We demonstrate its potential by wet-bench testing three predictions; that casein kinase-1 (PfCK1) is a specific Rab5B interacting protein and that the catalytic subunit of cAMP-dependent protein kinase A (PfPKA-C) is a PfRab5A and PfRab7 effector. CONCLUSIONS: The establishment of a shared set of physical Ypt/PfRab-effector proteins sheds light on a core set Plasmodium Rab-interactants shared with yeast. The PfRab-interactome should benefit vesicular trafficking studies in malaria parasites. The recruitment of PfCK1 to PfRab5B+ and PfPKA-C to PfRab5A+ and PfRab7+ vesicles, respectively, suggests that PfRab-recruited kinases potentially play a role in early and late endosome function in malaria parasites.


Assuntos
Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Animais , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Família Multigênica , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
15.
Microbiol Res ; 273: 127411, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37285689

RESUMO

Salmonella is a genus of widely spread Gram negative, facultative anaerobic bacteria, which is known to cause »th of diarrheal morbidity and mortality globally. It causes typhoid fever and gastroenteritis by gaining access to the host gut through contaminated food and water. Salmonella utilizes its biofilm lifestyle to strongly resist antibiotics and persist in the host. Although biofilm removal or dispersal has been studied widely, the inhibition of the initiation of Salmonella Typhimurium (STM WT) biofilm remains elusive. This study demonstrates the anti-biofilm property of the cell-free supernatant obtained from a carbon-starvation induced proline peptide transporter mutant (STM ΔyjiY) strain. The STM ΔyjiY culture supernatant primarily inhibits biofilm initiation by regulating biofilm-associated transcriptional network that is reversed upon complementation (STM ΔyjiY:yjiY). We demonstrate that abundance of FlgM correlates with the absence of flagella in the STM ΔyjiY supernatant treated WT cells. NusG works synergistically with the global transcriptional regulator H-NS. Relatively low abundances of flavoredoxin, glutaredoxin, and thiol peroxidase might lead to accumulation of ROS within the biofilm, and subsequent toxicity in STM ΔyjiY supernatant. This work further suggests that targeting these oxidative stress relieving proteins might be a good choice to reduce Salmonella biofilm.


Assuntos
Salmonella typhimurium , Febre Tifoide , Humanos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Biofilmes , Prolina/metabolismo
16.
J Dev Orig Health Dis ; 14(3): 437-448, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36632790

RESUMO

In The Pune Maternal Nutrition Study, vitamin B12 deficiency was seen in 65% of pregnant women, folate deficiency was rare. Maternal total homocysteine concentrations were inversely associated with offspring birthweight, and low vitamin B12 and high folate concentrations predicted higher offspring adiposity and insulin resistance. These findings guided a nested pre-conceptional randomised controlled trial 'Pune Rural Intervention in Young Adolescents'. The interventions included: (1) vitamin B12+multi-micronutrients as per the United Nations International Multiple Micronutrient Antenatal Preparation, and proteins (B12+MMN), (2) vitamin B12 (B12 alone), and (3) placebo. Intervention improved maternal pre-conceptional and in-pregnancy micronutrient nutrition. Gene expression analysis in cord blood mononuclear cells in 88 pregnancies revealed 75 differentially expressed genes between the B12+MMN and placebo groups. The enriched biological processes included G2/M phase transition, chromosome segregation, and nuclear division. Enriched pathways included, mitotic spindle checkpoint and DNA damage response while enriched human phenotypes were sloping forehead and decreased head circumference. Fructose-bisphosphatase 2 (FBP2) and Cell Division Cycle Associated 2 (CDCA2) genes were under-expressed in the B12 alone group. The latter, involved in chromosome segregation was under-expressed in both intervention groups. Based on the role of B-complex vitamins in the synthesis of nucleotides and S-adenosyl methionine, and the roles of vitamins A and D on gene expression, we propose that the multi-micronutrient intervention epigenetically affected cell cycle dynamics. Neonates in the B12+MMN group had the highest ponderal index. Follow-up studies will reveal if the intervention and the altered biological processes influence offspring diabesity.


Assuntos
Sangue Fetal , Micronutrientes , Recém-Nascido , Feminino , Adolescente , Gravidez , Humanos , Índia , Vitaminas , Vitamina B 12 , Ácido Fólico
17.
J Biol Chem ; 286(9): 7116-22, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21209094

RESUMO

Heat shock protein 90 participates in diverse biological processes ranging from protein folding, cell cycle, signal transduction and development to evolution in all eukaryotes. It is also critically involved in regulating growth of protozoa such as Dictyostelium discoideum, Leishmania donovani, Plasmodium falciparum, Trypanosoma cruzi, and Trypanosoma evansi. Selective inhibition of Hsp90 has also been explored as an intervention strategy against important human diseases such as cancer, malaria, or trypanosomiasis. Giardia lamblia, a simple protozoan parasite of humans and animals, is an important cause of diarrheal disease with significant morbidity and some mortality in tropical countries. Here we show that the G. lamblia cytosolic hsp90 (glhsp90) is split in two similar sized fragments located 777 kb apart on the same scaffold. Intrigued by this unique arrangement, which appears to be specific for the Giardiinae, we have investigated the biosynthesis of GlHsp90. We used genome sequencing to confirm the split nature of the giardial hsp90. However, a specific antibody raised against the peptide detected a product with a mass of about 80 kDa, suggesting a post-transcriptional rescue of the genomic defect. We show evidence for the joining of the two independent Hsp90 transcripts in-trans to one long mature mRNA presumably by RNA splicing. The splicing junction carries hallmarks of classical cis-spliced introns, suggesting that the regular cis-splicing machinery may be sufficient for repair of the open reading frame. A complementary 26-nt sequence in the "intron" regions adjacent to the splice sites may assist in positioning the two pre-mRNAs for processing. This is the first example of post-transcriptional rescue of a split gene by trans-splicing.


Assuntos
Giardia lamblia/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Protozoários/genética , Processamento Pós-Transcricional do RNA/fisiologia , Splicing de RNA/fisiologia , Anticorpos/farmacologia , Especificidade de Anticorpos , Genoma , Proteínas de Choque Térmico HSP90/imunologia , Proteínas de Protozoários/imunologia , Precursores de RNA/genética , RNA de Protozoário/genética
18.
Viruses ; 15(1)2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36680170

RESUMO

Monkeypox is an infectious zoonotic disease caused by an Orthopoxvirus and results in symptoms similar to smallpox. In a recent outbreak, monkeypox virus (MPXV) cases have been reported globally since May 2022, and the numbers are increasing. Monkeypox was first diagnosed in humans in the Democratic Republic of Congo and has now spread to throughout Europe, the USA, and Africa. In this study, we analyzed the whole genome sequences of MPXV sequences from recent outbreaks in various countries and performed phylogenomic analysis. Our analysis of the available human MPXV strains showed the highest mutations per sample in 2022 with the average number of mutations per sample being the highest in South America and the European continents in 2022. We analyzed specific mutations in 11 Indian MPXV strains occurring in the variable end regions of the MPXV genome, where the mutation number was as high as 10 mutations per gene. Among these, envelope glycoproteins, the B2R protein, the Ankyrin repeat protein, DNA polymerase, and the INF alpha receptor-like secreted glycoprotein were seen to have a relatively high number of mutations. We discussed the stabilizing effects of the mutations in some of the highly mutating proteins. Our results showed that the proteins involved in binding to the host receptors were mutating at a faster rate, which empowered the virus for active selection towards increased disease transmissibility and severity.


Assuntos
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Mpox/diagnóstico , Filogenia , DNA Polimerase Dirigida por DNA/genética , Mutação
19.
Microbiol Resour Announc ; 11(5): e0124621, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35471061

RESUMO

We report five canine rabies virus genome sequences from India that were obtained from brain samples using Oxford Nanopore Technologies sequencing. The sequences will facilitate understanding of the evolution and transmission of rabies.

20.
ACS Chem Neurosci ; 13(7): 1030-1045, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35200010

RESUMO

Parkinson's disease (PD) with cognitive impairment (PDCI) is essentially diagnosed through clinical and neuropsychological examinations. There is a need to identify biomarkers to foresee cognitive decline in them. We performed label-free unbiased nontargeted proteomics (Q-TOF LC/MS-MS) on the CSF of non-neurological control; PDCI; PD; and normal pressure hydrocephalus (NPH) patients, followed by targeted ELISA for validation. Of the 281 proteins identified, 42 were differentially altered in PD, PDCI, and NPH. With a certain overlap, 28 proteins were altered in PDCI and 25 proteins were altered in NPH. Five significantly upregulated proteins in PDCI were fibrinogen, gelsolin, complement factor-H, and apolipoproteins A-I and A-IV, whereas carnosine dipeptidase-1, carboxypeptidase-E, dickkopf-3, and secretogranin-3 precursor proteins were downregulated. Those uniquely altered in NPH were the insulin-like growth factor-binding protein, ceruloplasmin, α-1 antitrypsin, VGF nerve growth factor, and neural cell adhesion molecule L1-like protein. The ELISA-derived protein concentrations correlated with neuropsychological scores of certain cognitive domains. In PDCI, the Wisconsin card sorting percentile correlated negatively with fibrinogen. Intraperitoneal injection of native fibrinogen caused motor deficits in C57BL/6J mice as assessed by the pole test. Thus, a battery of proteins such as fibrinogen-α-chain, CFAH, and APOA-I/APOA-IV alongside neuropsychological assessment could be reliable biomarkers to distinguish PDCI and NPH.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Animais , Biomarcadores/metabolismo , Cognição , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Fator H do Complemento , Ensaio de Imunoadsorção Enzimática , Fibrinogênio , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Testes Neuropsicológicos , Doença de Parkinson/diagnóstico , Proteômica
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