Challenge 09: Skills, knowledge, and technology for all
Permanent URI for this collectionhttps://repository.unesco.gov.ph/handle/123456789/26
Ocean Decade
Challenge 09:
Skills, knowledge, and technology for all
Ensure comprehensive capacity development and equitable access to data, information, knowledge and technology across all aspects of ocean science and for all stakeholders.
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- Modified oxylipins as inhibitors of biofilm formation in Staphylococcus epidermidisPeran, Jacquelyn E.; Salvador-Reyes, Lilibeth A. (Frontiers Media SA, 2024-05-23)New approaches to combating microbial drug resistance are being sought, with the discovery of biofilm inhibitors considered as alternative arsenal for treating infections. Natural products have been at the forefront of antimicrobial discovery and serve as inspiration for the design of new antibiotics. We probed the potency, selectivity, and mechanism of anti-biofilm activity of modified oxylipins inspired by the marine natural product turneroic acid. Structure-activity relationship (SAR) evaluation revealed the importance of the trans-epoxide moiety, regardless of the position, for inhibiting biofilm formation. trans-12,13-epoxyoctadecanoic acid (1) and trans-9,10 epoxyoctadecanoic acid (4) selectively target the early stage of biofilm formation, with no effect on planktonic cells. These compounds interrupt the formation of a protective polysaccharide barrier by significantly upregulating the ica operon’s transcriptional repressor. This was corroborated by docking experiment with SarA and scanning electron micrographs showing reduced biofilm aggregates and the absence of thread-like structures of extrapolymeric substances. In silico evaluation revealed that 1 and 4 can interfere with the AgrA-mediated communication language in Staphylococci, typical to the diffusible signal factor (DSF) capacity of lipophilic chains.
- Diversity and novelty of venom peptides from Conus (Asprella) rolani revealed by analysis of its venom duct transcriptomeTaguchi, Ryoichi; Masacupan, Dan Jethro; Lluisma, Arturo (Philippine-American Academy of Science and Engineering, 2024-04-22)Conus species in the sub-genus Asprella are poorly studied because they inhabit deep-water habitats. To date, only a few peptides have been characterized from this clade. In this study, the venom duct transcriptome of a member of this clade, Conus rolani, was mined for potential conopeptides. Using a highthroughput RNA sequencing platform (Illumina) and a multiple k-mer de novo assembly, we found 103 putative conopeptide precursor amino acid sequences, including the few peptides previously reported for this species. The sequences, predominantly novel based on amino acid sequence, were diverse, comprising 36 gene superfamilies (including the “unassigned” superfamilies). As observed in other Conus species, the O1 gene superfamily was the most diverse (12 distinct sequences) but interestingly none of the sequences were found to contain the conserved amino acids associated with certain bioactivities in peptides found in piscivorous Conus species. The O2 superfamily was also highly diverse but conikot-ikot and an unassigned superfamily (MMSRMG) were more diverse than the rest of the superfamilies. In terms of gene expression levels, the understudied MEFRR paralog of the ancestral divergent M---L-LTVA superfamily was found to be the most highly expressed in the transcriptome, suggesting a novel role. Additionally, a conopeptide with high sequence similarity to A2 secretory group XII phospholipases is the first reported member of this phospholipase group in Conus and potentially represents a novel superfamily, expanding the catalog of known phospholipases present in cone snail venoms. The discovery of these putative conopeptides provides the first but early glimpse of the diversity and novelty of the peptides in the Asprella group and sets the stage for their functional characterization.This work was funded by the Department of Science and Technology- Philippine Council for Health Research and Development (DOST-PCHRD). The collection of C. rolani samples was made possible under Gratuitous Permit No. 0252- 23 granted by the Department of Agriculture — Bureau of Fisheries and Aquatic Resources, Philippines (DA-BFAR). The fieldwork was done with the help of Olango island fishermen, led by Antonio Mosqueda. We extend our gratitude to Antonio Catalig, Zae-Zae Aguinaldo, Kreighton Cadorna, Jonathan Wong, and Niño Dan Posadas for troubleshooting and assisting in the generation of the figures.