scholarly journals Antiviral Activity of CD437 Against Mumps Virus

2021 ◽  
Vol 12 ◽  
Author(s):  
Fumihiro Kato ◽  
Yuichiro Nakatsu ◽  
Keiko Murano ◽  
Aika Wakata ◽  
Toru Kubota ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Fluorescent Protein ◽  
Screening Method ◽  
Antiviral Drug ◽  
Mumps Virus ◽  
Screening Methods ◽  
Drug Candidates ◽  
Late Step ◽  
Key Factor ◽  
Green Fluorescent

Many efforts have been dedicated to the discovery of antiviral drug candidates against the mumps virus (MuV); however, no specific drug has yet been approved. The development of efficient screening methods is a key factor for the discovery of antiviral candidates. In this study, we evaluated a screening method using an Aequorea coerulescens green fluorescent protein-expressing MuV infectious molecular clone. The application of this system to screen for active compounds against MuV replication revealed that CD437, a retinoid acid receptor agonist, has anti-MuV activity. The point of antiviral action was a late step(s) in the MuV life cycle. The replication of other paramyxoviruses was also inhibited by CD437. The induction of retinoic acid-inducible gene (RIG)-I expression is a reported mechanism for the antiviral activity of retinoids, but our results indicated that CD437 did not stimulate RIG-I expression. Indeed, we observed antiviral activity despite the absence of RIG-I, suggesting that CD437 antiviral activity does not require RIG-I induction.

scholarly journals Rapid Screening Method for Compounds That Affect the Growth and Germination of Candida albicans, Using a Real-Time PCR Thermocycler

2011 ◽  
Vol 77 (22) ◽  
pp. 8193-8196 ◽  
Author(s):  
Lucja M. Jarosz ◽  
Bastiaan P. Krom
Keyword(s):  
Candida Albicans ◽  
Real Time ◽  
Real Time Pcr ◽  
Fluorescent Protein ◽  
Screening Method ◽  
Rapid Screening ◽  
Content Type ◽  
Wide Range ◽  
Hyphal Formation ◽  
Green Fluorescent

ABSTRACTWe propose a screening method for compounds affecting growth and germination inCandida albicansusing a real-time PCR thermocycler to quantify green fluorescent protein (GFP) fluorescence. Using PACT1-GFPand PHWP1-GFPreporter strains, the effects of a wide range of compounds on growth and hyphal formation were quantitatively assessed within 3 h after inoculation.

scholarly journals Establishment of a Stable Cell Line Coexpressing Dengue Virus-2 and Green Fluorescent Protein for Screening of Antiviral Compounds

2011 ◽  
Vol 17 (3) ◽  
pp. 283-292 ◽  
Author(s):  
V. Leardkamolkarn ◽  
W. Sirigulpanit
Keyword(s):  
Green Fluorescent Protein ◽  
Dengue Virus ◽  
Cell Line ◽  
Fluorescent Protein ◽  
Antiviral Drug ◽  
Stable Cell Line ◽  
Entry Site ◽  
Mouth Disease Virus ◽  
A Cell ◽  
Green Fluorescent

This study aimed to generate a stable cell line harboring subgenomic dengue virus replicon and a green fluorescent gene (DENV/GFP) for a cell-based model to screen anti-DENV compounds. The gene-encoding envelope protein of DENV-2 was deleted and then replaced with fragments of the GFP gene and a foot-and-mouth-disease virus 2A–derived cleavage site. The human cytomegalovirus immediate early and antisense hepatitis delta virus ribozyme sequences were added at the 5′- and 3′-ends. An internal ribosome entry site and neomycin resistance genes were placed upstream and next to the NS1 gene. The recombinant plasmids were propagated in a mammalian cell line. A stable cell line with the brightest green fluorescent protein and the highest viral protein and RNA expression was selected from six clones. The clone was then examined for effectiveness in an antiviral drug screening assay with compounds isolated from the local plants using two known antiviral agents as controls. Two novel flavones, PMF and TMF, were discovered having DENV-inhibitory properties. The data were validated by a conventional plaque titration assay. The results indicate that this newly developed cell line is efficient for use as a cell-based model for primary screening of anti-DENV compounds.

scholarly journals Elucidation on the Physicochemical Properties of Potential and Clinically Approved Antiviral Drugs: A Search for Effective Therapies against SARS-CoV-2 Infection

2020 ◽  
Vol 14 (suppl 1) ◽  
pp. 1025-1034
Author(s):  
Derick Erl P. Sumalapao
Keyword(s):  
Antiviral Activity ◽  
Physicochemical Properties ◽  
Vaccine Development ◽  
Heavy Atom ◽  
Antiviral Drug ◽  
Principal Component ◽  
Antiviral Drugs ◽  
Medical Emergency ◽  
Drug Candidates ◽  
Additional Information

COVID-19 has been confirmed in millions of individuals worldwide, rendering it a global medical emergency. In the absence of vaccines and the unavailability of effective drugs for the SARS-CoV-2 infection, vaccine development is being continuously explored and several antiviral compounds and immunotherapies are currently being investigated. Given the high similarity in genetic identity between SARS-CoV and SARS-CoV-2, the present investigation identified the interaction between the physicochemical properties and the antiviral activity of different potential and clinically approved antiviral drugs against SARS-CoV using hierarchically weighted principal component analysis. Representative drugs from the classes of neuraminidase inhibitors, reverse transcriptase inhibitors, protease inhibitors, nucleoside analogues, and other compounds with potential antiviral activity were examined. The pharmacologic classification and the biological activity of the different antiviral drugs were described using indices, namely, rotatable bond count, molecular weight, heavy atom count, and molecular complexity (92.32% contribution rate). The physicochemical properties and inhibitory action against SARS-CoV-2 of lopinavir, chloroquine, ivermectin, and ciclesonide validated the adequacy of the current computational approach. The findings of the present study provide additional information, although further investigation is warranted to identify potential targets and establish exact mechanisms, in the emergent search and design of antiviral drug candidates and their subsequent synthesis as effective therapies for COVID-19.

scholarly journals Boceprevir, calpain inhibitors II and XII, and GC-376 have broad-spectrum antiviral activity against coronaviruses in cell culture

2020 ◽  
Author(s):  
Yanmei Hu ◽  
Chunlong Ma ◽  
Tommy Szeto ◽  
Brett Hurst ◽  
Bart Tarbet ◽  
...  
Keyword(s):  
Cell Culture ◽  
Antiviral Activity ◽  
Cathepsin L ◽  
Antiviral Drug ◽  
Antiviral Effect ◽  
Neutralization Assay ◽  
Drug Candidates ◽  
Main Protease ◽  
Human Coronaviruses ◽  
Calpain Inhibitors

AbstractAs the COVID-19 pandemic continues to fold out, the morbidity and mortality are increasing daily. Effective treatment for SARS-CoV-2 is urgently needed. We recently discovered four SARS-CoV-2 main protease (Mpro) inhibitors including boceprevir, calpain inhibitors II and XII and GC-376 with potent antiviral activity against infectious SARS-CoV-2 in cell culture. Despite the weaker enzymatic inhibition of calpain inhibitors II and XII against Mpro compared to GC-376, calpain inhibitors II and XII had more potent cellular antiviral activity. This observation promoted us to hypothesize that the cellular antiviral activity of calpain inhibitors II and XII might also involve the inhibition of cathepsin L in addition to Mpro. To test this hypothesis, we tested calpain inhibitors II and XII in the SARS-CoV-2 pseudovirus neutralization assay in Vero E6 cells and found that both compounds significantly decreased pseudoviral particle entry into cells, indicating their role in inhibiting cathepsin L. The involvement of cathepsin L was further confirmed in the drug time-of-addition experiment. In addition, we found that these four compounds not only inhibit SARS-CoV-2, but also SARS-CoV, MERS-CoV, as well as human coronaviruses (CoVs) 229E, OC43, and NL63. The mechanism of action is through targeting the viral Mpro, which was supported by the thermal shift binding assay and enzymatic FRET assay. We further showed that these four compounds have additive antiviral effect when combined with remdesivir. Altogether, these results suggest that boceprevir, calpain inhibitors II and XII, and GC-376 are not only promising antiviral drug candidates against existing human coronaviruses, but also might work against future emerging CoVs.

Differential CTX-M Expression from a Conserved Promoter: Role of Promoter-Associated Spacer Sequences Downstream of the blaCTX-M Regulon

2016 ◽  
Vol 26 (4) ◽  
pp. 284-290 ◽  
Author(s):  
Lin Liu ◽  
Xiangyan Zhang ◽  
Siyuan Yang ◽  
Yao Zhai ◽  
Weijia Liu ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Green Fluorescent Protein ◽  
Promoter Activity ◽  
Expression Vector ◽  
Fluorescent Protein ◽  
Gfp Expression ◽  
Qrt Pcr ◽  
Key Factor ◽  
Green Fluorescent

<b><i>Aims:</i></b> The aim of this project was to explore the different CTX-M expression levels occurring from a single conserved promoter with different spacer sequences, the variation of which is hypothesized to be a key factor in fluctuating levels of CTX-M. <b><i>Methods:</i></b> The <i>bla</i><sub>CTX-M</sub> promoter fragments with five different spacer sequences were amplified, sequenced and cloned into the pUA66 expression vector carrying the green fluorescent protein (GFP) gene. The expression of <i>bla</i><sub>CTX-M</sub> in the transconjugants was analyzed using fluorescence microscopy, flow cytometry and qRT-PCR. <b><i>Results:</i></b> The promoters of all the <i>bla</i><sub>CTX-M</sub> genes were provided by IS<i>Ecp1 </i>and were extremely conserved. The promoter-associated spacer sequences varied from 42 to 127 bp and variations in GFP expression in the five transconjugants were observed. A nucleic acid deletion and point mutation were detected in the spacer sequences by variations in which the expression of <i>bla</i><sub>CTX-M</sub> was influenced. <b><i>Conclusion:</i></b> The different spacer sequences have a significant impact on the activity of the conserved promoter. The shorter spacer sequence between the conserved promoter and the <i>bla</i><sub>CTX-M</sub> gene does not specifically enhance the expression of<i> bla</i><sub>CTX-M</sub>, contrary to previous reports. The expression of <i>bla</i><sub>CTX-M</sub> may be regulated by changes in promoter activity caused by diverse spacer sequences.

scholarly journals Bud23 Methylates G1575 of 18S rRNA and Is Required for Efficient Nuclear Export of Pre-40S Subunits

2008 ◽  
Vol 28 (10) ◽  
pp. 3151-3161 ◽  
Author(s):  
Joshua White ◽  
Zhihua Li ◽  
Richa Sardana ◽  
Janusz M. Bujnicki ◽  
Edward M. Marcotte ◽  
...  
Keyword(s):  
Nuclear Export ◽  
Ribosome Biogenesis ◽  
18S Rrna ◽  
Fluorescent Protein ◽  
Ribosomal Subunit ◽  
Small Subunit ◽  
Nuclear Accumulation ◽  
Methyltransferase Activity ◽  
Late Step ◽  
Green Fluorescent

ABSTRACT BUD23 was identified from a bioinformatics analysis of Saccharomyces cerevisiae genes involved in ribosome biogenesis. Deletion of BUD23 leads to severely impaired growth, reduced levels of the small (40S) ribosomal subunit, and a block in processing 20S rRNA to 18S rRNA, a late step in 40S maturation. Bud23 belongs to the S-adenosylmethionine-dependent Rossmann-fold methyltransferase superfamily and is related to small-molecule methyltransferases. Nevertheless, we considered that Bud23 methylates rRNA. Methylation of G1575 is the only mapped modification for which the methylase has not been assigned. Here, we show that this modification is lost in bud23 mutants. The nuclear accumulation of the small-subunit reporters Rps2-green fluorescent protein (GFP) and Rps3-GFP, as well as the rRNA processing intermediate, the 5′ internal transcribed spacer 1, indicate that bud23 mutants are defective for small-subunit export. Mutations in Bud23 that inactivated its methyltransferase activity complemented a bud23Δ mutant. In addition, mutant ribosomes in which G1575 was changed to adenosine supported growth comparable to that of cells with wild-type ribosomes. Thus, Bud23 protein, but not its methyltransferase activity, is important for biogenesis and export of the 40S subunit in yeast.

scholarly journals New Chalcone Derivatives as Effective Anti-SARS-CoV-2 Agents

2021 ◽  
Author(s):  
Nizami Duran ◽  
M. Fatih Polat ◽  
Derya Anil Aktas ◽  
M. Abdullah Alagoz ◽  
Emrah Ay ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Antiviral Drug ◽  
Rt Pcr ◽  
Chalcone Derivatives ◽  
Drug Candidates ◽  
Angelica Keiskei ◽  
Antiviral Activities ◽  
Computational Analyses ◽  
Dose Dependent ◽  
Related Compounds

Abstract Flavonoids and related compounds, such as quercetin-based antiviral drug Gene-Eden-VIR/Novirin, inhibit the protease of severe acute respiratory syndrome coronavirus (SARS-CoV-2). The alkylated chalcones isolated from Angelica keiskei inhibit SARS-CoV proteases. Hydroxychloroquine and Favipiravir have been used in many countries since the beginning of the pandemic with the thought that they may have antiviral activity against SARS CoV-2. In this study, we aimed to compare the anti-SARS CoV-2 activities of both newly synthesized chalcone derivatives and these two drugs.The current study aimed to determine the potent antiviral activity of newly synthesized chalcone derivatives against SARS-CoV-2 by calculating the RT-PCR cycling threshold (Ct) values. Antiviral activities of the compounds varied due to being dose dependent. Compound 6, 7, 9 and 16 were highly effective against SARS-CoV-2 at concentrations of 1.60 µg/mL. Structure-based virtual screening was carried out against the most important druggable SARS-CoV-2 targets, viral RNA-dependent RNA polymerase (RdRp), to identify putative inhibitors that could facilitate the development of potential anti-COVID-19 drug candidates. Computational analyses identified eight compounds inhibiting each target, with binding affinity scores ranging from − 4,370 to -2,748 kcal/mol along with their toxicological, ADME, and drug-like properties.

scholarly journals Product-Induced Gene Expression, a Product-Responsive Reporter Assay Used To Screen Metagenomic Libraries for Enzyme-Encoding Genes

2010 ◽  
Vol 76 (21) ◽  
pp. 7029-7035 ◽  
Author(s):  
Taku Uchiyama ◽  
Kentaro Miyazaki
Keyword(s):  
Gene Expression ◽  
Fluorescent Protein ◽  
Screening Method ◽  
Metagenomic Library ◽  
Gene Cassette ◽  
Reporter Assay ◽  
Gene Encoding ◽  
E Coli ◽  
Green Fluorescent ◽  
Encoding Genes

ABSTRACT A reporter assay-based screening method for enzymes, which we named product-induced gene expression (PIGEX), was developed and used to screen a metagenomic library for amidases. A benzoate-responsive transcriptional activator, BenR, was placed upstream of the gene encoding green fluorescent protein and used as a sensor. Escherichia coli sensor cells carrying the benR-gfp gene cassette fluoresced in response to benzoate concentrations as low as 10 μM but were completely unresponsive to the substrate benzamide. An E. coli metagenomic library consisting of 96,000 clones was grown in 96-well format in LB medium containing benzamide. The library cells were then cocultivated with sensor cells. Eleven amidase genes were recovered from 143 fluorescent wells; eight of these genes were homologous to known bacterial amidase genes while three were novel genes. In addition to their activity toward benzamide, the enzymes were active toward various substrates, including d- and l-amino acid amides, and displayed enantioselectivity. Thus, we demonstrated that PIGEX is an effective approach for screening novel enzymes based on product detection.

Casein kinase I controls a late step in the endocytic trafficking of yeast uracil permease

2002 ◽  
Vol 115 (1) ◽  
pp. 217-226 ◽  
Author(s):  
Christelle Marchal ◽  
Sophie Dupré ◽  
Daniele Urban-Grimal
Keyword(s):  
Plasma Membrane ◽  
Green Fluorescent Protein ◽  
Fluorescent Protein ◽  
Casein Kinase ◽  
Casein Kinase I ◽  
Direct Role ◽  
Casein Kinase 1 ◽  
Late Step ◽  
Prevacuolar Compartment ◽  
Green Fluorescent

The modification of yeast uracil permease by phosphorylation at the plasma membrane is a key mechanism for regulating transporter endocytosis. Uracil permease is phosphorylated at several serine residues within a well characterized PEST sequence. The phosphorylation of these residues facilitates the ubiquitination and internalization of the permease. Following endocytosis, the permease is targeted to the lysosome/vacuole for proteolysis. We have shown that in casein kinase 1 (CK1)-deficient cells, the permease is poorly phosphorylated, poorly ubiquitinated and that Yck activity may play a direct role in phosphorylating the permease. We show here that CK1-deficient cells accumulated permease that was subjected to endocytosis in an internal compartment on its way to the vacuole. Uracil permease, produced as a fusion protein with green fluorescent protein in CK1-deficient cells, was detected in dots adjacent to the vacuole. These dots probably correspond to the late endosome/prevacuolar compartment because they were partially colocalized with the Pep12p marker. This accumulation was abolished by mutations affecting the adaptor-related complex, AP-3. The CPY and ALP pathways to the vacuole were both unaffected in CK1-deficient cells. Our analysis provides the first evidence that CK1 is important for the delivery of proteins to the vacuole after endocytosis.

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