scholarly journals Molecular Viral Diagnosis and Sanitation of Yam Genetic Resources: Implications for Safe Yam Germplasm Exchange

Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1101
Author(s):  
Marie Umber ◽  
Denis Filloux ◽  
Suzia Gélabale ◽  
Rose-Marie Gomez ◽  
Armelle Marais ◽  
...  

Yam (Dioscorea spp.) is an important crop in tropical and subtropical regions. Many viruses have been recently identified in yam, hampering genetic conservation and safe international exchanges of yam germplasm. We report on the implementation of reliable and cost-effective PCR-based detection tools targeting eight different yam-infecting viruses. Viral indexing of the in vitro yam collection maintained by the Biological Resources Center for Tropical Plants (BRC-TP) in Guadeloupe (French West Indies) unveiled a high prevalence of potyviruses, badnaviruses, Dioscorea mosaic associated virus (DMaV) and yam asymptomatic virus 1 (YaV1) and a high level of coinfections. Infected yam accessions were subjected to a combination of thermotherapy and meristem culture. Sanitation levels were monitored using PCR-based and high-throughput sequencing-based diagnosis, confirming the efficacy and reliability of PCR-based detection tools. Sanitation rates were highly variable depending on viruses. Sixteen accessions were successfully sanitized, paving the way to safe yam germplasm exchanges and the implementation of clean seed production programs worldwide.

2021 ◽  
Vol 12 ◽  
Author(s):  
Céline Nourrisson ◽  
Julien Scanzi ◽  
Julie Brunet ◽  
Frédéric Delbac ◽  
Michel Dapoigny ◽  
...  

Blastocystis is the most frequently isolated protozoan from human stool. Its role in human health is still debated, and a high prevalence was reported in irritable bowel syndrome (IBS) subjects, suggesting a potential link with microbiota. In the present study, we aimed to investigate prokaryotic and eukaryotic microbiota in both IBS-C (constipated) and healthy individuals. We recruited 35 IBS-C patients and 23 healthy subjects, from which 12 and 11 carried Blastocystis, respectively. We performed 16S and 18S rRNA high-throughput sequencing on feces. Whereas we did not observe differences between infected and non-infected controls, several phyla were significantly modified in IBS-C patients according to the presence of Blastocystis. Tenericutes phylum and Ruminococcaceae family were especially increased in Blastocystis carriers. Furthermore, colonization with Blastocystis was associated with discrete changes in the microbial eukaryome, particularly among the Fungi taxa. Depending on the group of patients considered, the mycobiota changes do not go in the same direction and seem more deleterious in the IBS-C group. These results encourage further in vivo and in vitro investigations concerning the role of Blastocystis in the gut environment.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Simin Salehzadeh ◽  
Mohammad Tabatabaei ◽  
Abdollah Derakhshandeh ◽  
Hamidreza Karbalaei-Heidari ◽  
Nasrin Kazemipour

Abstract Background The current study was aimed at evaluating the role of the N-SH2 domain of SHP-2 as a partner protein in the expression of a toxic peptide, laterosporulin (LTS). We also investigated its effects on the formation of the disulfide bond and functional folding of the peptide in vitro. The N-SH2-LTS protein was expressed as a His-tagged fusion protein, capable of undergoing enzymatic cleavage. Results Based on the data presented herein, the total yield of the folded fusion protein from inclusion bodies was found to be about 105 mg/l, demonstrating a high-level of heterologous expression. After enzymatic cleavage, 1.5 mg of the folded recombinant laterosporulin was obtained from each 10 mg of the fusion protein. The purity of the recombinant laterosporulin was analyzed by RP-HPLC, to yield peptides with suitable purity (85%). Conclusions Our findings indicated the advantages of using the N-SH2 domain of SHP-2 as a rapid and easy approach not only in producing easy target proteins but also in its function as a chaperone. N-SH2 domain of SHP-2 can influence on the purification of laterosporulin at reasonable yield and in a cost-effective fashion. The N-SH2 domain of SHP-2 as a protein chaperone may be potentially favorable to produce other proteins with disulfide bonds.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Laetitia Aznar-Cormano ◽  
Julie Bonnald ◽  
Sabrina Krief ◽  
Nelson Guma ◽  
Régis Debruyne

AbstractIt is important to determine the sex of elephants from their samples—faeces from the field or seized ivory—for forensic reasons or to understand population demography and genetic structure. Molecular sexing methods developed in the last two decades have often shown limited efficiency, particularly in terms of sensitivity and specificity, due to the degradation of DNA in these samples. These limitations have also prevented their use with ancient DNA samples of elephants or mammoths. Here we propose a novel TaqMan-MGB qPCR assay to address these difficulties. We designed it specifically to allow the characterization of the genetic sex for highly degraded samples of all elephantine taxa (elephants and mammoths). In vitro experiments demonstrated a high level of sensitivity and low contamination risks. We applied this assay in two actual case studies where it consistently recovered the right genotype for specimens of known sex a priori. In the context of a modern conservation survey of African elephants, it allowed determining the sex for over 99% of fecal samples. In a paleogenetic analysis of woolly mammoths, it produced a robust hypothesis of the sex for over 65% of the specimens out of three PCR replicates. This simple, rapid, and cost-effective procedure makes it readily applicable to large sample sizes.


eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Bo Lu ◽  
Liting Dong ◽  
Danyang Yi ◽  
Meiling Zhang ◽  
Chenxu Zhu ◽  
...  

Tn5-mediated transposition of double-strand DNA has been widely utilized in various high-throughput sequencing applications. Here, we report that the Tn5 transposase is also capable of direct tagmentation of RNA/DNA hybrids in vitro. As a proof-of-concept application, we utilized this activity to replace the traditional library construction procedure of RNA sequencing, which contains many laborious and time-consuming processes. Results of Transposase-assisted RNA/DNA hybrids Co-tagmEntation (termed ‘TRACE-seq’) are compared to traditional RNA-seq methods in terms of detected gene number, gene body coverage, gene expression measurement, library complexity, and differential expression analysis. At the meantime, TRACE-seq enables a cost-effective one-tube library construction protocol and hence is more rapid (within 6 hr) and convenient. We expect this tagmentation activity on RNA/DNA hybrids to have broad potentials on RNA biology and chromatin research.


Author(s):  
Bugero N.V. ◽  
Ilyina N.A. ◽  
Aleksandrova S.M.

In addition to the classical pathogens, which are well understood and well identified, new pathogens with the potential to spread epidemiologically are being identified. Some of these little-known organisms are the simplest Blastocystis spp. blastocystostosis. The clinical significance of Blastocystis spp. and its pathogenicity are still under discussion. This parasite belongs to a group of single-celled eukaryotic organisms living in the colon of the human intestine. Blastocystis spp. is known to be found both in people with reduced immune status and in individuals without any clinical manifestation. It has been established that a sufficiently high degree of invasiveness is observed in persons with gastrointestinal tract diseases, dermatosis, allergic reactions, in patients with carriers of the human immunodeficiency virus, etc. Possessing persistence factors, protozoa blastocysts contribute to the inactivation of host defensive mechanisms, providing a stable anthogonistic effect. In recent years, many works have been devoted to the characteristics of the persistent properties of Blastocystis spr., however, individual properties of blastocysts, in particular, anticytokine activity (ACA), have not yet been studied. In this regard, the work studied the anticytokine activity of microorganisms isolated from healthy subjects and patients with gastrointestinal tract diseases. A high prevalence of the studied characteristic in the subjects was shown. The expression of anticytokine activity in the obtained isolates of blastocysts was the highest in the group of persons with gastric ulcer disease, which decreased in the order of duodenal ulcer, chronic cholecystitis, chronic gastritis, etc. The data obtained in this work on the high level of ACA expression in blastocyst isolates obtained from individuals with gastrointestinal diseases as compared with the control group enables to conclude that their exometabolites may influence the local cytokine balance [1], which supports the inflammatory process.


2018 ◽  
Vol 18 (5) ◽  
pp. 321-368 ◽  
Author(s):  
Juan A. Bisceglia ◽  
Maria C. Mollo ◽  
Nadia Gruber ◽  
Liliana R. Orelli

Neglected diseases due to the parasitic protozoa Leishmania and Trypanosoma (kinetoplastids) affect millions of people worldwide, and the lack of suitable treatments has promoted an ongoing drug discovery effort to identify novel nontoxic and cost-effective chemotherapies. Polyamines are ubiquitous small organic molecules that play key roles in kinetoplastid parasites metabolism, redox homeostasis and in the normal progression of cell cycles, which differ from those found in the mammalian host. These features make polyamines attractive in terms of antiparasitic drug development. The present work provides a comprehensive insight on the use of polyamine derivatives and related nitrogen compounds in the chemotherapy of kinetoplastid diseases. The amount of literature on this subject is considerable, and a classification considering drug targets and chemical structures were made. Polyamines, aminoalcohols and basic heterocycles designed to target the relevant parasitic enzyme trypanothione reductase are discussed in the first section, followed by compounds directed to less common targets, like parasite SOD and the aminopurine P2 transporter. Finally, the third section comprises nitrogen compounds structurally derived from antimalaric agents. References on the chemical synthesis of the selected compounds are reported together with their in vivo and/or in vitro IC50 values, and structureactivity relationships within each group are analyzed. Some favourable structural features were identified from the SAR analyses comprising protonable sites, hydrophobic groups and optimum distances between them. The importance of certain pharmacophoric groups or amino acid residues in the bioactivity of polyamine derived compounds is also discussed.


Author(s):  
Anchal Trivedi ◽  
Aparna Misra ◽  
Esha Sarkar ◽  
Anil K. Balapure

Background: In recent years, great progress has been made in reducing the high level of malaria suffering worldwide. There is a great need to evaluate drug resistance reversers and consider new medicines against malaria. There are many approaches to the development of antimalarial drugs. Specific concerns must be taken in to account in these approaches, in particular there requirement for very in expensive and simple use of new therapies and the need to limit drug discovery expenses. Important ongoing efforts are the optimisation of treatment with available medications, including the use of combination therapy. The production of analogs of known agents and the identification of natural products, the use of compounds originally developed against other diseases, the assessment of overcoming drug resistance and the consideration of new therapeutic targets. Liver and spleen are the important organs which are directly associated with malarial complications. Aim: An analysis the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Objective: To determine in-Vitro Effect of Chlorquine and Picroliv on Plasmodium Berghei Induced Alterations in the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Material and method: 1-Histological preparation of spleen explants for paraplast embedding 2-Biochemicalstudies (Enzymes (Atpase, ALP&GST) and the level of protein, Malondialdehyde (MDA). Result: Splenomegalyis one of the three main diagnostic parameters of malaria infection besides fever and anaemia. Many enzymes present in the liver and spleen may also be altered or liberated under different pathological conditions. Enzymes (ATPase, ALP&GST) and the level of protein, Malondialdehyde (MDA) content was found to increase in the liver and spleen explants during malarial infection. In the liver and spleen derived from parasitized CQ treated animals, the activity of all the above enzymes (ATPase, ALP&GST) and the level of protein & MDA of liver/spleen reversed towards the normal for all the 4or3 days of incubations. Picroliv efficacy decreased with the increment of parasitaemia and at 60%parasitaemia. Conclusion: Alkalinephosphatase (ALP) was found to increase with increasing parasitaemia. After the addition of Picroliv to the medium, a decrement in the activity was observed up to day 4 of culture.A similar positive effect of Picroliv was observed on the ATPase and ALP activity of spleen explants.DNA and protein contents also increased in the parasitized liver cultured in the presence of picroliv.On the contrary, in the spleen explants DNA, protein and MDA content were found to decrease after Picroliv supplementation to the culture medium.


2020 ◽  
Vol 65 (1) ◽  
pp. e01948-20
Author(s):  
Dalin Rifat ◽  
Si-Yang Li ◽  
Thomas Ioerger ◽  
Keshav Shah ◽  
Jean-Philippe Lanoix ◽  
...  

ABSTRACTThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant M. tuberculosis mutants in two mouse models of TB using a range of pretomanid doses. The frequency of spontaneous resistance was approximately 10−5 CFU. Whole-genome sequencing of 161 resistant isolates from 47 mice revealed 99 unique mutations, of which 91% occurred in 1 of 5 genes previously associated with nitroimidazole activation and resistance, namely, fbiC (56%), fbiA (15%), ddn (12%), fgd (4%), and fbiB (4%). Nearly all mutations were unique to a single mouse and not previously identified. The remaining 9% of resistant mutants harbored mutations in Rv2983 (fbiD), a gene not previously associated with nitroimidazole resistance but recently shown to be a guanylyltransferase necessary for cofactor F420 synthesis. Most mutants exhibited high-level resistance to pretomanid and delamanid, although Rv2983 and fbiB mutants exhibited high-level pretomanid resistance but relatively small changes in delamanid susceptibility. Complementing an Rv2983 mutant with wild-type Rv2983 restored susceptibility to pretomanid and delamanid. By quantifying intracellular F420 and its precursor Fo in overexpressing and loss-of-function mutants, we provide further evidence that Rv2983 is necessary for F420 biosynthesis. Finally, Rv2983 mutants and other F420H2-deficient mutants displayed hypersusceptibility to some antibiotics and to concentrations of malachite green found in solid media used to isolate and propagate mycobacteria from clinical samples.


2009 ◽  
Vol 54 (1) ◽  
pp. 103-108 ◽  
Author(s):  
Hassan Safi ◽  
Robert D. Fleischmann ◽  
Scott N. Peterson ◽  
Marcus B. Jones ◽  
Behnam Jarrahi ◽  
...  

ABSTRACT Mutations within codon 306 of the Mycobacterium tuberculosis embB gene modestly increase ethambutol (EMB) MICs. To identify other causes of EMB resistance and to identify causes of high-level resistance, we generated EMB-resistant M. tuberculosis isolates in vitro and performed allelic exchange studies of embB codon 406 (embB406) and embB497 mutations. In vitro selection produced mutations already identified clinically in embB306, embB397, embB497, embB1024, and embC13, which result in EMB MICs of 8 or 14 μg/ml, 5 μg/ml, 12 μg/ml, 3 μg/ml, and 4 μg/ml, respectively, and mutations at embB320, embB324, and embB445, which have not been identified in clinical M. tuberculosis isolates and which result in EMB MICs of 8 μg/ml, 8 μg/ml, and 2 to 8 μg/ml, respectively. To definitively identify the effect of the common clinical embB497 and embB406 mutations on EMB susceptibility, we created a series of isogenic mutants, exchanging the wild-type embB497 CAG codon in EMB-susceptible M. tuberculosis strain 210 for the embB497 CGG codon and the wild-type embB406 GGC codon for either the embB406 GCC, embB406 TGC, embB406 TCC, or embB406 GAC codon. These new mutants showed 6-fold and 3- to 3.5-fold increases in the EMB MICs, respectively. In contrast to the embB306 mutants, the isogenic embB497 and embB406 mutants did not have preferential growth in the presence of isoniazid or rifampin (rifampicin) at their MICs. These results demonstrate that individual embCAB mutations confer low to moderate increases in EMB MICs. Discrepancies between the EMB MICs of laboratory mutants and clinical M. tuberculosis strains with identical mutations suggest that clinical EMB resistance is multigenic and that high-level EMB resistance requires mutations in currently unknown loci.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jun Liu ◽  
Jipeng Li ◽  
Ke Wang ◽  
Haiming Liu ◽  
Jianyong Sun ◽  
...  

AbstractFork-head box protein M1 (FoxM1) is a transcriptional factor which plays critical roles in cancer development and progression. However, the general regulatory mechanism of FoxM1 is still limited. STMN1 is a microtubule-binding protein which can inhibit the assembly of microtubule dimer or promote depolymerization of microtubules. It was reported as a major responsive factor of paclitaxel resistance for clinical chemotherapy of tumor patients. But the function of abnormally high level of STMN1 and its regulation mechanism in cancer cells remain unclear. In this study, we used public database and tissue microarrays to analyze the expression pattern of FoxM1 and STMN1 and found a strong positive correlation between FoxM1 and STMN1 in multiple types of cancer. Lentivirus-mediated FoxM1/STMN1-knockdown cell lines were established to study the function of FoxM1/STMN1 by performing cell viability assay, plate clone formation assay, soft agar assay in vitro and xenograft mouse model in vivo. Our results showed that FoxM1 promotes cell proliferation by upregulating STMN1. Further ChIP assay showed that FoxM1 upregulates STMN1 in a transcriptional level. Prognostic analysis showed that a high level of FoxM1 and STMN1 is related to poor prognosis in solid tumors. Moreover, a high co-expression of FoxM1 and STMN1 has a more significant correlation with poor prognosis. Our findings suggest that a general FoxM1-STMN1 axis contributes to cell proliferation and tumorigenesis in hepatocellular carcinoma, gastric cancer and colorectal cancer. The combination of FoxM1 and STMN1 can be a more precise biomarker for prognostic prediction.


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