Biochemical characterisation and substrate-specific proteolytic diversity of venom metalloproteinases in African puff adders

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  By 4028mdk09 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=11200575 Biochemical characterisation and substrate-specific proteolytic diversity of venom metalloproteinases in African puff adders Abstract The puff adder ( Bitis arietans ) is a highly venomous viper responsible for many snakebite fatalities in Africa, yet there have been few geographically comprehensive analyses of its venom proteins, particularly of the proteases that play a key role in pathology of envenoming. To address this, we have isolated, identified and characterised the bioactivity of the venom metalloproteases of puff adders obtained from a range of localities. Prominent in all venoms was a PI snake venom metalloproteinase (SVMP), derived from a larger PII precursor. This protein existed as either non-glycosylated (21 kDa) or glycosylated, the latter containing either one (26 kDa) or two N-glycans (30 kDa). All the venoms we tested contained either one or the other form: none had...

Desiccation resistance of the spider Sicarius thomisoides (Walckenaer, 1847) (Araneae: Sicariidae) to different temperatures

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Desiccation resistance of the spider Sicarius thomisoides (Walckenaer, 1847) (Araneae: Sicariidae) to different temperatures

Abstract

Desert spiders generally are tolerant or resistant to desiccation, as they must develop strategies to live in high temperatures and prevent continued water loss. However, in extreme conditions, as the temperature increases, their metabolism increases, so they could lose water as the temperature rises. The objective of this work was to determine the effect of temperature on water loss in the spider Sicarius thomisoides. Spiders were subjected to different temperatures: 20 °C, 30 °C and 40 °C. Our results indicate that this spider has excellent resistance to desiccation, since, on average of the three temperatures, losing only 77.25 ± 3.14% of the initial weight at 40 °C, being able to resist extremely high temperatures. In addition, we could not determine a significant effect of body size. Water loss was similar among individuals of different stage of development.

Berríos, C., Martínez, M., & Taucare‐Ríos, A. (2026). Desiccation resistance of the spider <em>Sicarius thomisoides</em> (Walckenaer, 1847) (Araneae: Sicariidae) to different temperatures. Revista Chilena De Entomología, 52(1), 51–58. Retrieved from https://www.biotaxa.org/rce/article/view/88431