A green synthetic protocol to add a chemical function to a fully deprotected peptide to obtain a bioactive and/or fluorescent-labeled conjugate is reported. A range of S-conjugation reactions promoted by the commercially available LTA zeolite to introduce different substituents on peptide cysteine residues has been shown to take place in the solid state or in the presence of minimal amounts of organic solvent, with yields that are comparable to those of standard solution methods. The additional advantage of the procedure consists of easing the work up, for which green solvents, such as aqueous systems, can be employed. The protocol is implemented with microwave irradiation to shorten the reaction time as dielectric heating increases the diffusion rates of the mechanically milled reactants.
A microwave-assisted esterification reaction to prepare hyaluronan–curcumin derivatives by employing a solvent-free process was developed. In particular, a solid-state strategy to react two molecules characterized by totally different solubility profiles was developed. Hyaluronic acid, a highly hydrosoluble polysaccharide, was reacted with hydrophobic and even water-unstable curcumin. Microwave (MW) irradiation was employed to activate the reaction between the two solid compounds through the direct interaction with them and to preserve the integrity of the sensitive curcumin species. This new protocol can be considered efficient, fast, and also eco-friendly, avoiding the employment of toxic organic bases and solvents. A cytotoxicity test suggested that the developed hyaluronan–curcumin conjugate (HA-CUR) could be considered a candidate for its implementation as a new material. In addition, preliminary studies revealed promising anti-inflammatory activity and open future perspectives of further investigation.
Verdoliva V, Muzio G, Autelli R, Saviano M, Bedini E, De Luca S
The current coronavirus disease-2019 (COVID-19) pandemic is due to the novel coronavirus SARS-CoV-2. The scientific community has mounted a strong response by accelerating research and innovation, and has quickly set the foundation for understanding the molecular determinants of the disease for the development of targeted therapeutic interventions. The replication of the viral genome within the infected cells is a key stage of the SARS-CoV-2 life cycle. It is a complex process involving the action of several viral and host proteins in order to perform RNA polymerization, proofreading and final capping. This review provides an update of the structural and functional data on the key actors of the replicatory machinery of SARS-CoV-2, to fill the gaps in the currently available structural data, which is mainly obtained through homology modeling. Moreover, learning from similar viruses, we collect data from the literature to reconstruct the pattern of interactions among the protein actors of the SARS-CoV-2 RNA polymerase machinery. Here, an important role is played by co-factors such as Nsp8 and Nsp10, not only as allosteric activators but also as molecular connectors that hold the entire machinery together to enhance the efficiency of RNA replication.
Here we report on the most recent updates on experimental drugs successfully employed
in the treatment of the disease caused by SARS-CoV-2 coronavirus, also referred to as
COVID-19 (COronaVIrus Disease 19). In particular, several cases of recovered patients have
been reported after being treated with lopinavir/ritonavir (which is widely used to treat human
immunodeficiency virus (HIV) infection) in combination with the anti-flu drug oseltamivir. In
addition, remdesivir, which has been previously administered to Ebola virus patients, has also
proven effective in the U.S. against coronavirus, while antimalarial chloroquine and hydroxychloroquine,
favipiravir and co-administered darunavir and umifenovir (in patient therapies)
were also recently recorded as having anti-SARS-CoV-2 effects. Since the recoveries/deaths
ratio in the last weeks significantly increased, especially in China, it is clear that the experimental
antiviral therapy, together with the availability of intensive care unit beds in hospitals
and rigorous government control measures, all play an important role in dealing with this virus.
This also stresses the urgent need for the scientific community to devote its efforts to the
development of other more specific antiviral strategies.
The first outbreak of COVID-19 in Italy occurred during the second half of February 2020 in some areas in the North of the country. Due to the high contagiousness of the infection, further spread by asymptomatic people,
Italy has become in a few weeks the country with the greatest number of infected people in the world. The large number of severe cases among infected people in Italy led to the hospitalization of thousands of patients, with a heavy burden on the National Health Service.
Methods
We analyzed data provided daily by Italian Authorities for the period from 24 February 2020 to 30 March 2020. Considering such information, we developed a forecast model in real-time, based on the cumulative log-logistic distribution.
Results
A total of 101,739 infected individuals were confirmed until 30 March 2020, of which 14,620 recovered or discharged, and 11,591 deaths. Until the same date patients quarantined at home were 43,752, whereas hospitalized patients were 31,776, of which 3981 in intensive care. The active cases (i.e. the number of patients not yet recovered until that date) were 75,528. The forecast model estimated a number of infected persons for Italy of 234,000 about, and a duration of the epidemic of approximately 4 months.
Conclusions
One month after the first outbreaks there seemed to be the first signs of a decrease in the number of infections, showing that we could be now facing the descending phase of the epidemic. The forecast obtained thanks to our model could be used by decision-makers to implement coordinative and collaborative efforts in order to control the epidemic.
The pandemic due to novel Coronavirus must be a warning for all countries worldwide, regarding a rapid and complete dissemination of information, surveillance, health organization, and cooperation among the states.
Prep1 is a homeodomain transcription factor belonging to the TALE protein family. Its overexpression affects glucose metabolism in several tissues. In particular, in skeletal muscle tissue the interaction of Prep1 with its cofactor p160 impairs GLUT4 expression and glucose uptake. In this study, we show that ceramides (C2cer), a class of lipids antagonizing insulin signalling, increase the levels of Prep1 and p160 in a dose and time-dependent fashion in L6 cells and induce their association by 80%. We find that C2cer exposure inhibits insulin receptor, IRS1 and Akt phosphorylation and reduces insulin-stimulated glycogen content and glucose uptake by 1.3- and 2.1-fold, respectively. The synthetic Prep1(54-72) peptide, mimicking the Prep1 region involved in the interaction with p160, reduces in vitro Prep1-p160 binding in a dose-dependent way (IC(50) = 0.20μM). In C2cer-treated L6 cells, 10μM Prep1(54-72) restores insulin signalling impaired by ceramide treatment. Prep1 overexpressing L6 cells display similar metabolic alterations observed in ceramide-treated L6 cells and the presence of Prep1(54-72) mitigates these events. All these findings suggest that disruption of the Prep1/p160 molecular interaction enhances insulin sensitivity impaired by ceramides in skeletal muscle cells and indicate this complex as an important target for type 2 diabetes.
Cimmino I, Lorenzo V, Fiory F, Doti N, Ricci S, Cabaro S, Liotti A, Vitagliano L, Longo M, Miele C, Formisano P, Beguinot F, Ruvo M, Oriente F
Haemophilus influenzae type b (Hib) is one of the leading causes of invasive bacterial infection in young children, characterized by inflammation mainly mediated by cytokines and chemokines. One of the most abundant components of the Hib outer membrane is the P2 porin, which has been shown to induce the release of several inflammatory cytokines. Synthetic peptides corresponding to loops L5, L6, and L7 activate JNK and p38 mitogen-activated protein kinase (MAPK) pathways, L7 being the most active peptide. Therefore, sequence-activity relationships and key residues were identified by elongating sequence to different extents, designing cyclic peptides, and performing an alanine scan of L7. The ability of mutant peptides to induce activation of signal transduction pathways and release of TNF-alpha and IL-6 has been determined, and, in conjunction with CD spectra, bioinformatics analysis, and molecular dynamics data, showed that 6 out of 8 amino acids contribute significantly to the overall activity. Molecular dynamics showed that L7 modifications increased loop rigidity and helicity after Gly6 mutation, thus, providing a possible structural explanation for observed loss of bioactivity. This work provides insights into essential molecular details of P2 that may impact on the pathogenesis of Hib infections where interruption of the signaling cascade could represent an attractive therapeutic strategy.
Galdiero S, Vitiello M, Amodeo P, D'Isanto M, Cantisani M, Pedone C, Galdiero M
The rise of antibiotic-resistant Klebsiella pneumoniae, a leading nosocomial pathogen, prompts the need for alternative therapies. We have identified and characterized a novel depolymerase enzyme encoded by Klebsiella phage KP36 (depoKP36), from the Siphoviridae family. To gain insights into the catalytic and structural features of depoKP36, we have recombinantly produced this protein of 93.4 kDa and showed that it is able to hydrolyze a crude exopolysaccharide of a K. pneumoniae host. Using in vitro and in vivo assays, we found that depoKP36 was also effective against a native capsule of clinical K. pneumoniae strains, representing the K63 type, and significantly inhibited Klebsiella-induced mortality of Galleria mellonella larvae in a time-dependent manner. DepoKP36 did not affect the antibiotic susceptibility of Klebsiella strains. The activity of this enzyme was retained in a broad range of pH values (4.0-7.0) and temperatures (up to 45 degrees C). Consistently, the circular dichroism (CD) spectroscopy revealed a highly stability with melting transition temperature (Tm) = 65 degrees C. In contrast to other phage tailspike proteins, this enzyme was susceptible to sodium dodecyl sulfate (SDS) denaturation and proteolytic cleavage. The structural studies in solution showed a trimeric arrangement with a high beta-sheet content. Our findings identify depoKP36 as a suitable candidate for the development of new treatments for K. pneumoniae infections.
Majkowska-skrobek G, Latka A, Berisio R, Maciejewska B, Squeglia F, RomanoM, Lavigne R, Struve C, Drulis-kawa Z
Viruses (ISSN: 1999-4915, 1999-4915linking, 1999-4915electronic), 2016 Dec 1; 8(12): N/D-N/D
The Institute of Biostructures and Bioimaging (IBB) of the National Research Council (CNR) has 100 staff units distributed in Naples and Turin (70 researchers / technologists) and carries out translational research for the development of new tools for prevention, diagnosis and targeted therapies.
To accomplish these objectives, researchers studying biomolecules from a structural and functional point of view collaborate with experts in preclinical imaging that study cellular and animal models of human diseases and clinical researchers carrying out experiments in humans.
Research activities include basic research, a laboratory for the preclinical imaging of small animals and clinical research areas carried out in collaboration with universities and other research institutions. The combination of design and testing expertise, both in vitro and in vivo, of new diagnostic and therapeutic agents with expertise in multiple imaging modalities (including MRI, optical imaging, PET / SPECT, ultrasound, CT) provide the interdisciplinary bases to carry out a truly innovative research in the field of molecular imaging and personalized therapy. The IBB has a consolidated experience in the research of biomarkers of various pathologies, design and synthesis of molecules able to interact with certain biomarkers and preclinical validation of the molecules developed.
Another research area developed by IBB is e-Health. The activity aims to create open-source software systems, consisting of models, services and tools to support diagnosis, therapy and follow-up, as well as for the innovative management of health processes.
The Institute is part of the Italian node of the European Research Infrastructure for Imaging Technologies in Biological and Biomedical Sciences (Euro-BioImaging, EuBI).
The fundamental activity of the Institute of Biostructures and Bioimaging consists of the following research areas:
• Design, synthesis, expression and structural characterization of molecules of biological interest, and their interactions with metal ions. Applications in the diagnostic and therapeutic field.
• Biochemical technologies and biostructures;
• Biochemical technologies aimed at diagnostic imaging;
• Image diagnostics and radiotherapy;
• Preclinical and clinical molecular imaging. New diagnostic / teragnostics agents for Molecular Imaging;
• Development of innovative technological e-health solutions, with particular attention to the issues of telemedicine and assisted diagnosis.