Rational attenuation of elapid long-chain neurotoxin by targeted residue substitution and disulfide architecture simplification: implications for receptor interaction and immune recognition

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  Rational attenuation of elapid long-chain neurotoxin by targeted residue substitution and disulfide architecture simplification: implications for receptor interaction and immune recognition Abstract Elapid long-chain neurotoxins (LNTxs) exert their toxicity through high-affinity binding to nicotinic acetylcholine receptors (nAChRs). Specific residues mediate this process, including basic (Lys23, Arg33, Arg36, Lys49), structural (Cys26, Cys30), and aromatic (Phe29) amino acids. To investigate the functional and immunogenic implications of modifying these residues, we designed two recombinant variants of a consensus LNTx. The first variant, rLcNTx V1, contains charge-reversal mutations at four key basic positions, while the second, rLcNTx V2, lacks the segment corresponding to the fifth disulfide bond. We expressed both variants in Escherichia coli Origami cells. rLcNTx V1 was recovered in a soluble form, but rLcNTx V2 was present only in inclusion bodies. We assessed the binding ...

New and interesting spiders (Arthropoda, Araneae) from Vashlovani National Park and Chachuna Managed Reserve (Georgia). Part II

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New and interesting spiders (Arthropoda, Araneae) from Vashlovani National Park and Chachuna Managed Reserve (Georgia). Part II

Spiders collected individually during short outings at different locations, as well as during a trip to Vashlovani National Park and Chachuna Managed Reserve, were identified, resulting in the recognition of 22 species, of which three are described as new: Harpactea digitata Seropian, sp. nov. (♂, Dedoplistskaro) (Dysderidae), Leptopilos longiembolus Seropian & Japaridze, sp. nov. (♂, Vashlovani National Park), and Palpimanus obscurus Seropian & Bulbulashvili, sp. nov. (♂♀, Georgia, Azerbaijan, and Iran) (Palpimanidae). A female of Synema inexpectatum Seropian, Bulbulashvili, Makharadze & Baznikin, 2024, collected with several males, is described, while the species is recorded for the first time from the Kvemo Kartli region. Furthermore, Bogdocosa kronebergi (Andreeva, 1976), Marinarozelotes adriaticus (Caporiacco, 1951), and Pseudicius palaestinensis Strand, 1915 are recorded in Georgia for the first time. Diagnostic drawings and photographs of preserved specimens are included, along with detailed collecting data.

Seropian, A., Bulbulashvili, N., Makharadze, G., Zukakishvili, A. & Japaridze, L.-G. (2026b). New and interesting spiders (Arthropoda, Araneae) from Vashlovani National Park and Chachuna Managed Reserve (Georgia). Part II. Zootaxa 5814(1): 43-67. doi: 10.11646/zootaxa.5814.1.2