The biotechnological value of a novel potent marine biotoxin from the polychaete worm Eulalia viridis: chemical and toxicological evaluation

• Autor(a) principal: Rodrigo, Ana Patrícia Carreira
• Data de Publicação: 2020
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/116178
• topic: Blue Economy; in vitro assays; Mucus; Phyllotoxins; Proteomics; Transcriptomic; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia do Ambiente

The ocean’s vastness holds still many unexplored organisms with unique adaptive features that enable them to thrive in their environment. Eulalia viridis is one of them. This uncanny bright green worm is a predatory marine Polychaeta of the rocky intertidal that lacks jaws, but it is equipped with a toxin-containing mucus that enables predating larger invertebrates from which soft tissue is extracted through suction. Motivated by the high-value of toxins as bioreactives and by the European Union’s ambitions of leading the Blue Growth Strategy, for which Portugal’s vast EEZ offers high perspectives; a case-study to explore the biotechnological potential of this species was undertaken. The worm’s microanatomy revealed key adaptations for feeding such as special sensorial papillae and cells responsible for the secretion of mucus and toxins. Whole-transcriptome sequencing and toxicity assays yielded a complex pattern of proteinaceous toxins and enzymes with several functions: tissue permeabilization, coagulation impairment and blocking of neuromuscular activity. The main neurotoxins, “phyllotoxins”, found to be cysteine-rich proteins, act as immobilising agents against mussels and other invertebrate prey and are delivered by contact with mucus. In turn, higher toxicity towards ovarian cancer cell line (A2780) than normal cells, involved cytotoxic and cytostatic properties through cell cycle arrest and extrinsic programmed cell death. Several proteins involved in these effects were identified by combining transcriptomics and proteomics. The worm’s mucosecretions also hold internalisable proteinaceous complexes that display fluorescent properties and whose emission is reversibly switched by redox status. Altogether, the features found in the secretions of a single species disclose the immense biotechnological potential of marine annelids, and invertebrates in general, as source of valuable bio-reactives, even in temperate waters. The methodological pipeline, combining ecology, toxicology and molecular biology, circumvented many difficulties of marine bioprospecting and is an important contribution for the sustainable exploitation of novel marine bioresources.