Advances in the phytochemical screening and biological potential of propolis.

Propolis is a natural resinous product collected from different parts of plants by bees and mixed with their salivary secretions. The occurrence of more than 180 different chemotypes has flavonoids, phenolic acids, esters, and phenolic aldehydes, as well as balsamic resins, beeswax, pollen, and essential and aromatic oils, among others. Its biological potential documented throughout the world justifies the need, from time to time, to organize reviews on the subject, with the intention of gathering and informing about the update on propolis. In this review (CRD42020212971), phytochemical advances, in vitro, in vivo, and clinical biological assays of pharmacological interest are showcased. The focus of this work is to present propolis clinical safety assays, antitumor, analgesic, antioxidant, anti-inflammatory, and antimicrobial activities. This literature review highlights propolis' promising biological activity, as it also suggests that studies associating propolis with nanotechnology should be further explored for enhanced bioprocessing applications.

Identification of potential Staphylococcus aureus dihydrofolate reductase inhibitors using QSAR, molecular docking, dynamics simulations and free energy calculation.

Herein we describe the use of molecular docking simulations, quantitative structure-activity relationships studies and ADMETox predictions to analyse the molecular recognition of a series of 7-aryl-2,4-diaminoquinazoline derivatives on the inhibition of Staphylococcus aureus dihydrofolate reductase and conducted a virtual screening to discover new potential inhibitors. A quantitative structure-activity relationship model was developed using 40 compounds and two selected descriptors. These descriptors indicated the importance of pKa and molar refractivity for the inhibitory activity against SaDHFR. The values of R2train, CVLOO and R2test generated by the model were 0.808, 0.766, and 0.785, respectively. The integration between QSAR, molecular docking, ADMETox analysis and molecular dynamics simulations with binding free energies calculation, yielded the compounds PC-124127620, PC-124127795 and PC-124127805 as promising candidates to SaDHFR inhibitors. These compounds presented high potency, good pharmacokinetics and toxicological profile. Thus, these molecules are good potential antimicrobial agent to treatment of infect disease caused by S. aureus.Communicated by Ramaswamy H. Sarma.

Association strength of E6 to E6AP/p53 complex correlates with HPV-mediated oncogenesis risk.

Human papillomavirus (HPV) is recognized as the causative agent of cervical cancer in women, and it is associated with other anogenital and head/neck cancers. More than 120 types of HPV have been identified and many classified as high- or low-risk according to their oncogenic potential. One of its proteins, E6, has evolved to overcome the oncosuppressor functions of p53 by targeting this protein for degradation via interaction with the human ubiquitin-ligase E6AP. This study evaluates the correlation between the association strength of 40 HPV E6 types to the E6AP/p53 complex and the HPV oncogenesis risk using molecular simulations and machine and deep learning (ML/DL). In addition, a ML/DL-driven prediction is proposed for the HPV unclassified oncogenic risk type. The results indicate that thermodynamics play a pivotal role in the establishment of HPV-associated cancer and highlight the need to include some viral types in the HPV-related cancer surveillance and prevention strategies.