Soil Preference and Burrow Characteristics of Two Theraphosidae Species in Penang Island, Malaysia

  Soil Preference and Burrow Characteristics of Two Theraphosidae Species in Penang Island, Malaysia Abstract Tarantulas play a crucial role in maintaining ecological balance by regulating insect populations. However, little is known about the soil preferences and burrow structures of tarantulas in Malaysia. This study aims to determine the soil preference as well as the burrow structure of  Coremiocnemis cunciularia  and  Chilobrachys andersoni  from Penang Island. The soil characteristics of the soil samples collected around the burrows of  Coremiocnemis cunciularia  (n = 30) and  Chilobrachys andersoni  (n = 30) were determined using soil texture analysis. The measurements and burrow structures from adults and juveniles of  Coremiocnemis cunciularia  and  Chilobrachys andersoni  were determined. It was revealed that the moisture content and clay percentage in the soil samples around burrows of  Chilobrachys anderso...

Predictive analysis of B-cell antigenic epitopes in phospholipase D toxins from Loxosceles spiders

 


Predictive analysis of B-cell antigenic epitopes in phospholipase D toxins from Loxosceles spiders

Abstract

The Phospholipase D (PLD) toxin family, a major component of the Loxosceles spider venom, is a valuable biotechnological tool for developing antivenom treatment and diagnostic assays to overcome and prevent loxoscelism. However, there is limited knowledge about the antigenic structure of the PLD family or if sequence diversity correlates with antigenic variability. This study aimed to evaluate the possible antigenic diversity of PLDs sequences among different species of spiders of the Loxosceles genus through a predictive analysis of potential continuous and discontinuous antigenic epitopes of two phylogenetic interspecies clusters. Thus, L. laeta had higher amino acid sequence variation than other species, being classified into three phylogenetic clusters at the intra-specie level. Furthermore, multiple alignments of consensus PLD sequences from each Loxosceles species showed two different phylogenetic clusters at interspecies level depending on the amino acid conservation. For each cluster, at least nine continuous antigenic domains were identified, and depending on the phylogenetic cluster belonging to the Loxosceles species, the PLD continuous and discontinuous antigenic structure varies. Also, L. laeta PLDs vary significantly within the Loxosceles species and possess their own antigenic structure compared to other species with common continuous epitopes. Finally, the catalytic loop was identified as a common discontinuous epitope in the PLDs independently of the cluster or the class it belongs to. This antigenic diversity of PLD toxins could have implications for antibody recognition and should be considered in the design strategies for the development of serum treatments and diagnostic assays to detect Loxosceles venom.
Catalán, A., García, C., Sambra, V., Cadena, N., Rojas, J., Arán-Sekul, T., San Francisco, J., Vásquez-Saez, V., Muñoz, C., Vásquez, A., & Araya, J. E. (2025). Predictive analysis of B-cell antigenic epitopes in phospholipase D toxins from Loxosceles spiders. Toxicon: X, 26, 100222. https://doi.org/10.1016/j.toxcx.2025.100222