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Plasmodium falciparum exclusively harbours a non-photosynthetic plastid-like organelle called 'apicoplast,' crucial for survival. The apicoplast genome resembles chloroplasts, albeit much reduced at 35 kb. The housekeeping functions of the apicoplast are similar to prokaryotes, and several antibiotics have been reported to kill the malaria parasite by targeting its housekeeping functions. However, a significant structural difference between bacterial and apicoplast housekeeping proteins promotes the discovery of antibiotic analogs specifically targeting apicoplast proteins. In this study, we used a high-throughput virtual screening approach to analyze 80% of structurally similar antibiotic analog libraries against five protein targets, including histone-like protein (PfHU), gyrase A subunit (PfGyrA), RNA polymerase β subunit (PfRpoβ), elongation factor G (PfEF-G), and elongation factor Tu (PfEF-Tu) involved in different housekeeping functions of the apicoplast. This computational screening identified molecules with better binding affinities than those antibiotics shown to have antimalarial activities, suggesting they may be more potent antimalarial compounds. The molecular dynamics simulations study revealed stable conformational changes with strong hydrogen bonds between the protein–ligand complexes. The top-hit antibiotic analogs exhibit favourable drug-like characteristics, making them promising candidates for future clinical studies. We propose further biochemical and phenotypic testing of these antibiotic analogs to develop more effective apicoplast-targeting antimalarials. [ABSTRACT FROM AUTHOR]

Monkeypox is a zoonotic disease caused by the Poxviridiea family virus Monkeypox. According to the Centers for Disease Control and Prevention, 70,420 monkeypox virus infections had been reported in 107 countries as of October 6, 2022. New studies have concluded that the monkeypox outbreak is caused by a strain with a unique mutation, increasing the possibility that the virus may develop resistance to current medicines by accumulating mutations in therapeutic targets. As peptide‐based therapeutics impede the drug target through multiple interactions, it may offer a better therapeutic solution to the possible drug resistance issue related to monkeypox treatment. Therefore, in this work, we screened an antiviral peptide library, the CPP site 2.0 database, against the p37 target protein using molecular docking approaches. The p37 is required for the viral pathogen's successful egression and spread. The allergenicity and physicochemical properties of the peptides were thoroughly analyzed before the molecular docking studies for selecting druggable candidates. The interactions of the peptides bearing the highest docking score were validated further by using molecular dynamics (MD) simulation studies. Our investigation revealed that two cell‐penetrating peptides of the CPP site 2.0 database might effectively prevent the egression and spread of the MPXV by inhibiting p37. Following more testing, these peptides can be explored in developing peptide‐based therapies against the MPX therapy. [ABSTRACT FROM AUTHOR]

Dinoflagellates, apicomplexans and ciliates are members of the monophyletic supergroup of Alveolata. The protists of this phylogenetic cluster have adapted to various ecological niches and lifestyles. Dinoflagellates and cilates can be found in any aquatic environment, whereas the phylum Apicomplexa solely comprises intracellular parasites. Despite their diversity all alveolates are united by the presence of membranous vesicles, so called alveoli, located beneath the plasma membrane. In addition to strengthening the cytoskeleton, these vesicles appear to possess taxon-specific functionality. In dinoflagellates and ciliates the alveoli predominantly play a structural role and can function as calcium stores. However, for the Apicomplexa, the alveolar vesicles -here jointly called the inner membrane complex (IMC)- are additionally involved in invasion of the host cell and are important scaffold elements during cytokinesis. Recent studies shed light on the architecture of the apicomplexan IMC and the number and diversity of its constituent proteins. This plethora of proteins and their varying evolutionary origin underlines the versatility of the IMC as a result of the adaption to a parasitic lifestyle.