The main viral protease (3CL pro ) is indispensable for SARS-CoV-2 replication. We delineate the human protein substrate landscape of 3CL pro by TAILS substrate-targeted N-terminomics. We identify >100 substrates in human lung and kidney cells supported by analyses of SARS-CoV-2-infected cells. Enzyme kinetics and molecular docking simulations of 3CL pro engaging substrates reveal how noncanonical cleavage sites, which diverge from SARS-CoV, guide substrate specificity. Cleaving the interactors of essential effector proteins, effectively stranding them from their binding partners, amplifies the consequences of proteolysis. We show that 3CL pro targets the Hippo pathway, including inactivation of MAP4K5, and key effectors of transcription, mRNA processing, and translation. We demonstrate that Spike glycoprotein directly binds galectin-8, with galectin-8 cleavage disengaging CALCOCO2/NDP52 to decouple antiviral-autophagy. Indeed, in post-mortem COVID-19 lung samples, NDP52 rarely colocalizes with galectin-8, unlike healthy lung cells. The 3CL pro substrate degradome establishes a foundational substrate atlas to accelerate exploration of SARS-CoV-2 pathology and drug design.

The EO of Lippia gracilis leaves shows antinociceptive and anti-inflammatory activities.

The essential oils from the leaves of Annona salzmannii and A. pickelii (Annonaceae) growing in Sergipe, northeastern region of Brazil, were obtained by hydrodistillation using a Clevenger-type apparatus, and analyzed by GC/MS and GC/FID. Thirty-four compounds were identified in the essential oil of A. salzmannii and twenty-seven in that of A. pickelii; sesquiterpenes predominated in both essential oils. Bicyclogermacrene (20.3%), (E)-caryophyllene (19.9%), -cadinene (15.3%), -copaene (10.0%), and allo-aromadendrene (5.7%) were the main components of A. salzmannii, and bicyclogermacrene (45.4%), (E)-caryophyllene (14.6%), and -copaene (10.6%) of A. pickelii. The essential oils showed significant antioxidant capacity in the ORAC FL and DPPH assays. The antimicrobial activity of these essential oils was also evaluated against bacteria and fungi, as well as the larvicidal activity against Aedes aegypti larvae.

No abstract

Lippia gracilis, popularly known in Brazil as 'alecrim-de-tabuleiro', is used for many purposes, especially antimicrobial and antiseptic activities. The leaves of three L. gracilis genotypes, including LGRA-106, LGRA-109 and LGRA-110 were collected from the Active Germplasm Bank located in the "Campus Rural da UFS" research farm at the São Cristóvão country, Sergipe State, Brazil. The essential oils were obtained from leaves of L. gracilis plants by hydrodistillation. Chemical analysis of the essential oils was performed by gas chromatography-mass spectrometry (GC-MS). The susceptibility of Trichophyton rubrum strains, MYA3108 and TruMDR2, to the two L. gracilis genotypes (LGRA-106 and LGRA-109) essential oils was determined by the serial microdilution method. Leishmanicidal activity of essential oil from LGRA-106 and LGRA-110 was assayed by tetrazolium-dye (MTT) colorimetric method. The oxygenated monoterpene thymol was the main component of the essential oil from genotype LGRA-106, while Carvacrol was more abundant in LGRA-109 and LGRA-110. The concentrations of LGRA-106 and LGRA-109 essential oils that completely eliminate the fungi were determined and these concentrations were similar to those observed for fluconazole, a common antifungal drug. Among the genotype tested, LGRA-106 essential oil exhibited the best fungicidal activity at 46.87μgmL(-1). Regarding to leishmanicidal activity, the IC50, for LGRA-106 and LGRA-110, was 86.32 and 77.26μgmL(-1), respectively. The results showed that L. gracilis essential oil, rich in thymol and thymol itself presented best antidermatophytic activity, while the best leishmanicidal activity was obtained with essential oil from genotype rich in Carvacrol and Carvacrol itself.

Production, content and chemical composition of essential oil of mint cultivated under color shading netsThis research was carried out to evaluate the intensive effect and spectral light quality transmitted by the shading nets related to Mentha arvensis plants growth, content and chemical composition. Two evaluations were performed, one 85 days after planting and the other one 80 days after plants reshoot. The experimental design was randomized complete blocks with 4 treatments and 5 replications, each plot with 3 pots (one plant per pot) in each cutting. The treatments consisted of mint cultured under full sun light and under shading net with 50% of black, red or blue screen. We evaluated the yield of dry leaves biomass, stalks, shoots, roots and stolons and total biomass, root/shoot ratio, total foliar area, foliar area ratio, foliar weight ratio, specific foliar area, shoots number after reshoots, content, yield and chemical composition of essential oil. The plants growth, essential oil content and yield were more affected by light intensity than spectral light quality transmitted by the shading nets. The shading of 50% by nets is excessive, independently on color. The chemical composition of essential oil was not affected considerably by color shading nets.

Cross-linking/Mass spectrometry (XLMS) is a consolidated technique for structural characterization of proteins and protein complexes. Despite its success, the cross-linking chemistry currently used is mostly based on N-hydroxysuccinimide (NHS) esters, which react primarily with lysine residues. One way to expand the current applicability of XLMS into several new areas is to increase the number of cross-links obtainable for a target protein. We introduce a multiplex chemistry (denoted XPlex) that targets Asp, Glu, Lys, and Ser residues. XPlex can generate significantly more cross-links with reactions occurring at lower temperatures and enables targeting proteins that are not possible with NHS ester-based cross-linkers. We demonstrate the effectiveness of our approach in model proteins as well as a target Lys-poor protein, SalBIII. Identification of XPlex spectra requires a search engine capable of simultaneously considering multiple cross-linkers on the same run; to achieve this, we updated the SIM-XL search algorithm with a search mode tailored toward XPlex. In summary, we present a complete chemistry/computational solution for significantly increasing the number of possible distance constraints by mass spectrometry experiments, and thus, we are convinced that XPlex poses as a real complementary approach for structural proteomics studies.

The composition of three samples of essential oil (EO) extracted from the leaves and flowers of Hyptis fruticosa (Lamiaceae) were investigated by GC/MS and GC-FID. The variability of the constituents and biological activity were evaluated in the oil samples. Acetic acid-induced abdominal constrictions and formalin-induced pain tests in mice were used for screening the antinociceptive activity. The possible antagonism of the essential oils or morphine (MOR) antinociceptive effects by pretreatment with naloxone, showed no influence on the antinociceptive action of the oils in the acetic acid-induced writhing test. All examined oil samples presented antinociceptive activity. The oil sample obtained from the leaves collected during the vegetative growth stage, near São Cristóvão at Sítio Tujubeba exhibited the highest effect. The same oil sample had a main percentage of 1,8-cineole (18.70%). Nevertheless, the oil obtained from flowers collected at the same location, showed a significant difference (p < 0.05) in the response intensity in the first phase of paw licking (100 mg/kg) possibly due to the higher contents of α-pinene (20.51%) and β-pinene (13.64%). The results provide evidence for the use of H. fruticosa by traditional medicine practitioners in the management of pain.