biostudies-literatureChacon JMinisterio de Ciencia y Tecnolog?aVicerrector?a de Investigaci?n, Universidad de Costa Rica2801-2815https://www.ebi.ac.uk/biostudies/studies/S-EPMC12150329biostudies-literatureUnknown24(6)We report the biochemical and proteomic characterization of the venom of the arboreal Talamancan palm-pitviper, <i>Bothriechis nubestris</i>, a species endemic to north and central parts of the Costa Rican Cordillera de Talamanca, at 2100 to 3000 m above sea level. The Talamancan palm-pitviper venom arsenal comprised the translated products of 26 unique transcripts into 10 toxin classes, where metalloproteinases PIIa and PIII represent the dominant components. <i>In vitro</i>, the venom proteolyzed azocasein and gelatin but showed no phospholipase A₂ or human plasma coagulant activities. <i>In vivo</i>, <i>B. nubestris</i> venom exhibited an intravenous median lethal dose (LD₅₀) of 21.5 (95% confidence interval: 15.6-29.5) μg/mouse, and a minimum hemorrhagic dose (MHDJournal of proteome researchSnake Venomics of the Arboreal Talamancan Palm-Pitviper, &lt;i&gt;Bothriechis nubestris&lt;/i&gt;, Provides Clues on the Origin of a Phenotypic Dichotomy between Type-I and Type-II Venoms.PMC12150329C0061BFU2020_PID2020-119593GB-I00Chacon JLomonte BFernandez JMena GSasa MBonilla FSanz LChang-Castillo AGutierrez JMCalvete JJDiaz CChaves-Araya SfalseSnake Venomics of the Arboreal Talamancan Palm-Pitviper, &lt;i&gt;Bothriechis nubestris&lt;/i&gt;, Provides Clues on the Origin of a Phenotypic Dichotomy between Type-I and Type-II Venoms.We report the biochemical and proteomic characterization of the venom of the arboreal Talamancan palm-pitviper, <i>Bothriechis nubestris</i>, a species endemic to north and central parts of the Costa Rican Cordillera de Talamanca, at 2100 to 3000 m above sea level. The Talamancan palm-pitviper venom arsenal comprised the translated products of 26 unique transcripts into 10 toxin classes, where metalloproteinases PIIa and PIII represent the dominant components. <i>In vitro</i>, the venom proteolyzed azocasein and gelatin but showed no phospholipase A₂ or human plasma coagulant activities. <i>In vivo</i>, <i>B. nubestris</i> venom exhibited an intravenous median lethal dose (LD₅₀) of 21.5 (95% confidence interval: 15.6-29.5) μg/mouse, and a minimum hemorrhagic dose (MHD2025-01-01T00:00:00Z2025 Jun2026-07-15T06:29:07.749Z2026-06-30T03:21:37.439ZS-EPMC121503294027717010.1021/acs.jproteome.4c01041