Paas, A. | Search bioRxiv

bioRxiv2024

Engineering a wolf spider A-family toxin towards increased antimicrobial activity but low toxicity

Peptides with insecticidal, antimicrobial and/or cytolytic activities, also known as spider venom antimicrobial peptides (AMPs), can be found in the venoms of RTA-clade spiders. They show translational potential as therapeutic leads. A set of 52 AMPs has been described in the Chinese wolf spider (Lycosa shansia), and many have been shown to exhibit antibacterial effects. Here we explored the potential to enhance their antimicrobial activity using bioengineering. We generated a panel of artificial derivatives of an A-family peptide and screened their activity against selected microbial pathogens, vertebrate cells and insects. In several cases, we increased the antimicrobial activity of the derivatives while retaining the low cytotoxicity of the parental molecule. Furthermore, we injected the peptides into adult Drosophila suzukii and found no evidence of insecticidal effects, confirming the low levels of toxicity. Our data therefore suggest that spider venom linear peptides can be modified into more potent antimicrobial agents that could help to battle infectious diseases in the future.

bioengineering↗

bioRxiv2023

Feasibility of cognitive neuroscience data collection during a speleological expedition

In human cognitive neuroscience and neuropsychology studies, laboratory-based research tasks have been important to establish principles of brain function and its relationship to behaviour; however, they differ greatly from real-life experiences. Several elements of real-life situations that impact human performance, such as stressors, are difficult or impossible to replicate in the laboratory. Expeditions offer unique possibilities for studying human cognition in complex environments that can transfer to other situations with similar features. For example, as caves share several of the physical and psychological challenges of safety-critical environments such as spaceflight, underground expeditions have been developed as an analogue for astronaut training purposes, suggesting that they might also be suitable for studying aspects of behaviour and cognition that cannot be fully examined under laboratory conditions. While a large range of topics and tools have been proposed for use in such environments, few have been evaluated in the field. We tested the feasibility of collecting human physiological, cognitive, and subjective experience data concerning brain state, sleep, cognitive workload, and fatigue, during a speleological expedition in a remote region. We document our approaches and challenges experienced, and provide recommendations and suggestions to aid future work. The data support the idea that cave expeditions are relevant naturalistic paradigms that offer unique possibilities for cognitive neuroscience to complement laboratory work and help improve human performance and safety in operational environments.

neuroscience↗