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1.
Commun Biol ; 5(1): 212, 2022 03 08.
Article in English | MEDLINE | ID: covidwho-1735294

ABSTRACT

Internalization of membrane proteins plays a key role in many physiological functions; however, highly sensitive and versatile technologies are lacking to study such processes in real-time living systems. Here we describe an assay based on bioluminescence able to quantify membrane receptor trafficking for a wide variety of internalization mechanisms such as GPCR internalization/recycling, antibody-mediated internalization, and SARS-CoV2 viral infection. This study represents an alternative drug discovery tool to accelerate the drug development for a wide range of physiological processes, such as cancer, neurological, cardiopulmonary, metabolic, and infectious diseases including COVID-19.


Subject(s)
Drug Discovery/methods , Membrane Proteins , Protein Transport/physiology , Spectrometry, Fluorescence/methods , COVID-19 , Drug Development/methods , HEK293 Cells , Humans , Luciferases/genetics , Luciferases/metabolism , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Microscopy, Fluorescence , Nanotechnology , Receptors, G-Protein-Coupled , SARS-CoV-2/chemistry , SARS-CoV-2/metabolism , Virus Internalization
2.
Biomed Pharmacother ; 146: 112513, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1575252

ABSTRACT

The interactions of four sulfonylated Phe(3-Am)-derived inhibitors (MI-432, MI-463, MI-482 and MI-1900) of type II transmembrane serine proteases (TTSP) such as transmembrane protease serine 2 (TMPRSS2) were examined with serum albumin and cytochrome P450 (CYP) isoenzymes. Complex formation with albumin was investigated using fluorescence spectroscopy. Furthermore, microsomal hepatic CYP1A2, 2C9, 2C19 and 3A4 activities in presence of these inhibitors were determined using fluorometric assays. The inhibitory effects of these compounds on human recombinant CYP3A4 enzyme were also examined. In addition, microsomal stability assays (60-min long) were performed using an UPLC-MS/MS method to determine depletion percentage values of each compound. The inhibitors showed no or only weak interactions with albumin, and did not inhibit CYP1A2, 2C9 and 2C19. However, the compounds tested proved to be potent inhibitors of CYP3A4 in both assays performed. Within one hour, 20%, 12%, 14% and 25% of inhibitors MI-432, MI-463, MI-482 and MI-1900, respectively, were degraded. As essential host cell factor for the replication of the pandemic SARS-CoV-2, the TTSP TMPRSS2 emerged as an important target in drug design. Our study provides further preclinical data on the characterization of this type of inhibitors for numerous trypsin-like serine proteases.


Subject(s)
Antiviral Agents/metabolism , Cytochrome P-450 Enzyme System/metabolism , Protease Inhibitors/metabolism , Serine Endopeptidases/metabolism , Serum Albumin, Human/metabolism , Antiviral Agents/analysis , Antiviral Agents/pharmacology , Dose-Response Relationship, Drug , Humans , Isoenzymes/metabolism , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Protease Inhibitors/analysis , Protease Inhibitors/pharmacology , Protein Binding/physiology , Serine Endopeptidases/analysis , Spectrometry, Fluorescence/methods , Tandem Mass Spectrometry/methods
3.
PLoS One ; 16(9): e0256621, 2021.
Article in English | MEDLINE | ID: covidwho-1394545

ABSTRACT

This paper describes a detailed study of spectral and time-resolved photoprocesses in human platelets and their complexes with platinum (Pt) nanoparticles (NPs). Fluorescence, quantum yield, and platelet amino acid lifetime changes in the presence and without femtosecond ablated platinum NPs have been studied. Fluorescence spectroscopy analysis of main fluorescent amino acids and their residues (tyrosine (Tyr), tryptophan (Trp), and phenylalanine (Phe)) belonging to the platelet membrane have been performed. The possibility of energy transfer between Pt NPs and the platelet membrane has been revealed. Förster Resonance Energy Transfer (FRET) model was used to perform the quantitative evaluation of energy transfer parameters. The prospects of Pt NPs usage deals with quenching-based sensing for pathology's based on platelet conformations as cardiovascular diseases have been demonstrated.


Subject(s)
Blood Platelets/chemistry , Fluorescence Resonance Energy Transfer/methods , Metal Nanoparticles/chemistry , Platinum/chemistry , Adult , Energy Transfer , Healthy Volunteers , Humans , Spectrometry, Fluorescence/methods
4.
FEBS Lett ; 595(18): 2341-2349, 2021 09.
Article in English | MEDLINE | ID: covidwho-1347384

ABSTRACT

Heparan sulfate (HS), a sulfated glycosaminoglycan (GAG), was reported to be a necessary host attachment factor that promotes SARS-CoV-2 infection. In this study, we developed GAG microarrays based on fluorescence detection for high-sensitivity screening of the GAG-binding specificity of proteins and applied it for the analysis of SARS-CoV-2 spike (S) protein. Among the 20 distinct GAGs, the S protein bound not only to heparin (HEP)/HS but also to chondroitin sulfate E (CSE) in a concentration-dependent manner. We then analyzed the specificity of each subunit of the S protein. While the S1 subunit showed exclusive binding to HEP, the S2 subunit also bound to CSE and HEP/HS. CSE might act as an alternative attachment factor for HS in SARS-CoV-2 infection.


Subject(s)
Chondroitin Sulfates/metabolism , Glycosaminoglycans/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Humans , Microarray Analysis , Protein Binding , Spectrometry, Fluorescence/methods
5.
J Am Chem Soc ; 143(30): 11544-11553, 2021 08 04.
Article in English | MEDLINE | ID: covidwho-1319014

ABSTRACT

Exponential molecular amplification such as the polymerase chain reaction is a powerful tool that allows ultrasensitive biodetection. Here, we report a new exponential amplification strategy based on photoredox autocatalysis, where eosin Y, a photocatalyst, amplifies itself by activating a nonfluorescent eosin Y derivative (EYH3-) under green light. The deactivated photocatalyst is stable and rapidly activated under low-intensity light, making the eosin Y amplification suitable for resource-limited settings. Through steady-state kinetic studies and reaction modeling, we found that EYH3- is either oxidized to eosin Y via one-electron oxidation by triplet eosin Y and subsequent 1e-/H+ transfer, or activated by singlet oxygen with the risk of degradation. By reducing the rate of the EYH3- degradation, we successfully improved EYH3--to-eosin Y recovery, achieving efficient autocatalytic eosin Y amplification. Additionally, to demonstrate its flexibility in output signals, we coupled the eosin Y amplification with photoinduced chromogenic polymerization, enabling sensitive visual detection of analytes. Finally, we applied the exponential amplification methods in developing bioassays for detection of biomarkers including SARS-CoV-2 nucleocapsid protein, an antigen used in the diagnosis of COVID-19.


Subject(s)
Coronavirus Nucleocapsid Proteins/analysis , Eosine Yellowish-(YS)/analogs & derivatives , Spectrometry, Fluorescence/methods , 3,3'-Diaminobenzidine/chemistry , Biomarkers/chemistry , Catalysis/radiation effects , Eosine Yellowish-(YS)/chemical synthesis , Eosine Yellowish-(YS)/radiation effects , Fluorescence , Light , Limit of Detection , Oxidation-Reduction/radiation effects , Phosphoproteins/analysis , Polyethylene Glycols/chemistry , Polymerization , Proof of Concept Study , SARS-CoV-2/chemistry
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 249: 119241, 2021 Mar 15.
Article in English | MEDLINE | ID: covidwho-1065570

ABSTRACT

The present work describes development of rapid, robust, sensitive and green spectrofluorimetric method for determination of favipiravir (FAV). Different factors affecting fluorescence were carefully studied and Box Behnken Design was applied to optimize experimental parameters. The proposed method is based on measuring native fluorescence of FAV in 0.2 M borate buffer (pH 8.0) at 432 nm after excitation at 361 nm. There was a linear relationship between FAV concentration and relative fluorescence intensity over the range 40-280 ng/mL with limit of detection of 9.44 ng/mL and quantitation limit of 28.60 ng/mL. The method was successfully implemented for determination of FAV in its pharmaceutical formulation with mean % recovery of 99.26 ± 0.87. Moreover, the high sensitivity of the method allowed determination of FAV in spiked human plasma over a range of 48-192 ng/mL. The proposed spectrofluorimetric method was proved to be eco-friendly according to analytical eco-scale.


Subject(s)
Amides/blood , Antiviral Agents/blood , COVID-19/blood , COVID-19/drug therapy , Pyrazines/blood , Spectrometry, Fluorescence/methods , Amides/analysis , Amides/therapeutic use , Antiviral Agents/analysis , Antiviral Agents/therapeutic use , Blood Chemical Analysis/methods , Blood Chemical Analysis/statistics & numerical data , Humans , Limit of Detection , Pyrazines/analysis , Pyrazines/therapeutic use , SARS-CoV-2 , Sensitivity and Specificity , Spectrometry, Fluorescence/statistics & numerical data
7.
Commun Biol ; 4(1): 70, 2021 01 15.
Article in English | MEDLINE | ID: covidwho-1033621

ABSTRACT

The proliferation and transmission of viruses has become a threat to worldwide biosecurity, as exemplified by the current COVID-19 pandemic. Early diagnosis of viral infection and disease control have always been critical. Virus detection can be achieved based on various plasmonic phenomena, including propagating surface plasmon resonance (SPR), localized SPR, surface-enhanced Raman scattering, surface-enhanced fluorescence and surface-enhanced infrared absorption spectroscopy. The present review covers all available information on plasmonic-based virus detection, and collected data on these sensors based on several parameters. These data will assist the audience in advancing research and development of a new generation of versatile virus biosensors.


Subject(s)
COVID-19/diagnosis , COVID-19/epidemiology , Pandemics , SARS-CoV-2/chemistry , Spectrum Analysis, Raman/methods , Surface Plasmon Resonance/methods , COVID-19/virology , Humans , Nanostructures/chemistry , Spectrometry, Fluorescence/methods , Spectrophotometry, Infrared/methods
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