Beyond Venom and Constriction: Bite Performance and Trophic Ecology in the Genus Drymarchon

  Beyond Venom and Constriction: Bite Performance and Trophic Ecology in the Genus Drymarchon Abstract Snakes exhibit extreme cranial kinesis that facilitates ingestion of prey with large cross-sectional area, but this ability is widely predicted to reduce bite performance due to decreased structural rigidity. Consequently, most large-bodied snakes rely on envenomation or constriction to subdue prey prior to ingestion. Species within the genus Drymarchon represent a notable exception: these large, non-venomous, non-constricting snakes routinely consume a wide range of prey, including large and potentially dangerous vertebrates, using only simple seizing and pinioning behaviors. Here, we quantify bite performance in three species of Drymarchon ( D. corais, D. couperi, and D. melanurus ), examine morphological predictors of biting performance, compare biting pressure to constriction pressure in similarly sized snakes, and synthesize dietary records across the genus. Our results sh...

Spider Venom Peptides as Potential Allosteric Inhibitors of Undecaprenyl Diphosphatase (UppP) from Acinetobacter baumannii: In Silico Identification and Structural Analysis

 

Spider Venom Peptides as Potential Allosteric Inhibitors of Undecaprenyl Diphosphatase (UppP) from Acinetobacter baumannii: In Silico Identification and Structural Analysis

Abstract

The antimicrobial resistance of Acinetobacter baumannii necessitates the development of novel therapeutic strategies targeting essential enzymes such as Undecaprenyl Pyrophosphate Phosphatase (UppP). This study explored spider venom peptides in silico as potential allosteric inhibitors of A. baumannii UppP. A systematic literature review was conducted to select eight α-helical peptides with reported anti-A. baumannii activity, followed by their computational physicochemical characterization. Three-dimensional models of A. baumannii UppP and the candidate peptides were generated, and a putative allosteric binding site was validated through molecular docking of a known inhibitor of the BacA homolog. The eight peptides were subsequently docked to this validated site using HADDOCK. Results revealed variable binding affinities; peptides LC-AMP-I1, Lycosin-II, and GK37 exhibited the most favorable HADDOCK scores and extensive interaction networks, consistent with their reported high antimicrobial potency. Other candidates, notably Lt-MAP2, showed low binding affinity but high predicted synergistic potential. These findings identify promising spider venom peptide candidates, suggesting dual (membrane disruption/UppP inhibition) or synergistic mechanisms of action, and validate UppP as a viable pharmacological target for peptide-based inhibitors.

Liscano, Y., Álvarez-Caballero, J. M., & Aragón-Muriel, A. (2026). Spider Venom Peptides as Potential Allosteric Inhibitors of Undecaprenyl Diphosphatase (UppP) from Acinetobacter baumannii: In Silico Identification and Structural Analysis. Toxins, 18(5). https://doi.org/10.3390/toxins18050210