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...

Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae)

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Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae)

Abstract

Maybe living Archaeidae is only distributed in the southern, but all their fossils have been found in the northern hemisphere. Here, we report a new well-preserved fossil specimen from Kachin amber, which was identified to be a new species of genus Eomysmauchenius Wunderlich, 2008 through a series of morphological characteristics comparison, including a strongly raised cephalic part, a sclerotized ring around the spinnerets and a pedipalpal-cheliceral stridulatory organ absence, cheliceral peg teeth in an irregular position, the distal lateral margin of chelicera with a small triangular projection, length and height almost equal opisthosoma. The discovery of this new species once again increases fossil record diversity of the family Archaeidae in the Cretaceous, and unique palp structure enrich our knowledge of juvenal male pedipalps.

Yuan Peng, Chao Shi, Xiaoxuan Long, Michael S. Engel, Shuo Wang, Discovery of a new species of Eomysmauchenius from mid-Cretaceous Kachin amber (Araneae: Archaeidae), Cretaceous Research, 2023, 105703, ISSN 0195-6671, https://doi.org/10.1016/j.cretres.2023.105703.

(https://www.sciencedirect.com/science/article/pii/S0195667123002318)