Remarkable micro-endemism and high congeneric richness: eight new cave-restricted species of Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from the Brazilian semi-arid

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  Remarkable micro-endemism and high congeneric richness: eight new cave-restricted species of Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from the Brazilian semi-arid Abstract Eight new species of pseudoscorpions belonging to the genus Pseudochthonius Balzan, 1892 are described from the semi-arid region of Brazil. Comprehensive morphological descriptions, diagnostic characters, detailed illustrations, and ecological remarks of the habitats are provided for Pseudochthonius celestialis sp. nov., P. caritas sp. nov., P. patientia sp. nov., P. temperantia sp. nov., P. diligentia sp. nov., P. castitas sp. nov., P. humilitas sp. nov., and P. benignitas sp. nov. In addition, we present a brief discussion of the potential factors underlying the remarkable congeneric species richness observed in this geographically restricted region, as well as the principal threats faced by these species. These findings underscore the importance of conserving caves in order to pr...

Inhibition of Chikungunya virus nsP2 protease in vitro by scorpion venom peptide pantinin-1

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Inhibition of Chikungunya virus nsP2 protease in vitro by scorpion venom peptide pantinin-1

Abstract

Climate change has facilitated the spread of arboviruses like the Chikungunya virus (CHIKV). CHIKV, a re-emerging virus from the Togaviridae family, has caused numerous global outbreaks. The absence of antiviral therapy against CHIKV poses a significant threat to public health. The cleavage of the viral polyprotein relies on the catalytic activity of nsP2, crucial for viral replication. Therefore the nsP2 protease presents a promising target for antiviral drug development. Animal venom-derived peptides demonstrated potential in combating various diseases including infections, cancer, and neurodegenerative disorders. In this study, we assessed the inhibitory effects of pantinin-1, a peptide derived from the scorpion Pandinus imperator with broad antimicrobial activity, against CHIKV nsP2 protease. Pantinin-1 effectively inhibited CHIKV nsP2 protease, with a half-maximal inhibitory concentration (IC₅₀) of 6.4 ± 2.04 µM and complete inhibition at 175 µM. Further examination revealed that pantinin-1 functions as a competitive inhibitor with low micromolar affinity and exhibited no toxicity up to 20 µM in cell culture. Using docking and molecular dynamics simulations, the protein-peptide interaction was analyzed, and the key residues involved in the protease binding were predicted. These findings underscore the potential of pantinin-1 as a lead candidate targeting nsP2 protease.

Mastalipour, M., Coronado, M. A., Hernández González, J. E., Willbold, D., & Eberle, R. J. (2026). Inhibition of Chikungunya virus nsP2 protease in vitro by scorpion venom peptide pantinin-1. PLOS ONE, 21(4), e0346930. https://doi.org/10.1371/journal.pone.0346930