Activity Determinants in Linear Spider Venom Peptide Fragments Against MRSA

  Activity Determinants in Linear Spider Venom Peptide Fragments Against MRSA Abstract Objective: Using neural networks, we previously identified linear fragments of spider venom peptides active against methicillin-resistant Staphylococcus aureus (MRSA). Among them, peptide IX (IWLSLMKFAGKHL-NH 2 ) with a C -terminal amide displayed high antibacterial potency, whereas its non-amidated analogue, peptide X, was inactive. Peptide IX incorporates into zwitterionic multilamellar liposomes of dioleoylphosphatidylcholine (DOPC) without disrupting them, and also into anionic liposomes of dioleoylphosphatidylglycerol (DOPG) mimicking the MRSA cell membrane, leading to bilayer disruption. This study aims to elucidate the reasons for peptide X inactivation.  Methods: According to ¹H NMR spectroscopy, peptide X in water is governed by the ionization of the His12 residue. ³¹P NMR data show that peptide X interacts with DOPC and DOPG membranes. Monte Carlo simulations revealed conformati...

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

 


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