The search for novel preventive and therapeutic strategies is paramount in response to the pressing challenge of limiting the spread of microbial infections in aquaculture. Synthetic antimicrobial agents have been widely employed but face the significant obstacle of bacterial resistance, posing threats to human health. In that sense, marine species represent a significant portion of global biodiversity and produce co mpounds with unique antibacterial properties, thus constituting a promising source for discovering natural bioactive compounds.
Within the Marie Skłodowska-Curie BIOPTAL project, we have focused on the cephalopod Octopus vulgaris , a potential reservoir of under explored peptide diversity. Given its relevance for aquaculture and the adaptability of octopi to environmental conditions, investigating its potential bioactive compounds under challenging circumstances holds significant promise for developing novel therapeutic solutions. To this end, t en adult specimens (Mediterranean Sea) were divided into control and challenged groups for an in vivo bacterial challenge with Vibrio parahaemolyticus , a common aquaculture bacterial pathogen. Then , skin samples were collected, and transcriptomics and proteomics analyses were conducted using state-of-the-art methodologies and custom pipelines to address the complexity of these non-model organism samples (Figure 1).
By analyzing their skin proteomes and transcriptomes , we identified several differentially expressed genes /proteins potentially related to O. vulgaris defense mechanisms that translated into a list of peptide candidates with potential antimicrobial activities against several targets, namely Gram-positive and/or Gram-negative bacteria, fungi, viruses and cancer cells (AMPpredictor, in-silico machine learning pre-screening).
Overall, this integrative multi-omics approach offers insights into the octopus’s defense mechanisms and its molecular adaptation to environmental stressors. This study contributes to a deeper understanding of the common octopus’s adaptive strategies, particularly in combating multi-antibiotic resistant bacteria prevalent in aquaculture, offering an interesting window for the bioprospection of antimicrobial peptides. Specifically, the insights gained may help optimize culture conditions and disease prevention strategies for aquaculture-relevant species.