03. Science and Technology (Natural Sciences) Committee
Permanent URI for this communityhttps://repository.unesco.gov.ph/handle/123456789/3
In creating a culture of peace and addressing sustainable development challenges, UNESCO aims to cultivate the generation and application of scientific knowledge among its Member States. At UNACOM, we facilitate access to UNESCO’s international programmes in the sciences, such as the Intergovernmental Oceanographic Commission (IOC), Man and the Biosphere (MAB) Programme, and International Geoscience and Geoparks Programme (IGGP), among others.
Through this sector, the Commission aims to contribute to the following SDGs: 11 - Sustainable Cities and Communities, 13 - Climate Action, 14 - Life Below Water, and 15 - Life On Land. With the overarching vision of the 2023-2028 Philippine Development Plan (PDP), UNACOM targets grassroots-inspired cultural heritage and biodiversity protection and conservation, as well as multi-stakeholder partnerships for SDGs promotion.
Through this sector, the Commission aims to contribute to the following SDGs: 11 - Sustainable Cities and Communities, 13 - Climate Action, 14 - Life Below Water, and 15 - Life On Land. With the overarching vision of the 2023-2028 Philippine Development Plan (PDP), UNACOM targets grassroots-inspired cultural heritage and biodiversity protection and conservation, as well as multi-stakeholder partnerships for SDGs promotion.
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- Synthesis and biological evaluation of cyanobacterial-inspired peptidesCasanova, Jannelle R.; Villaraza, Aaron Joseph L.; Salvador-Reyes, Lilibeth (Philippine-American Academy of Science and Engineering, 2024-03-18)Cyanobacteria are known producers of structurally diverse and potent natural products; the majority are peptides with unique modifications. Yet, there remains a huge underexplored chemodiversity from cyanobacteria. Here, we designed a linear octapeptide as a product of combinatorial peptide design inspired by the natural products from the filamentous cyanobacteria Hapalosiphon welwitschii and Leptolyngbya sp. The target peptide was synthesized via solid-phase peptide synthesis (SPPS) using fluorenylmethyloxycarbonyl-protecting group (Fmoc) strategy. Structural diversity was expanded by the substitution of unnatural amino acids to yield five analogues. The structure and sequence of the synthesized peptides were confirmed using nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). Biological activity evaluation was done; with none of the peptides showing antimicrobial or cytotoxic activities against microbial pathogens and mammalian cells, respectively. To our knowledge, this study is the first to report a combinatorial peptide design inspired by a natural product and a predicted biosynthetic product. This strategy of peptide design expands the chemistry of a known bioactive natural product with the aid of unexplored cyanobacterial biosynthetic gene clusters.
- Using constellation pharmacology to characterize a novel α-conotoxin from Conus ateralbusNeves, Jorge L. B.; Urcino, Cristoval; Chase, Kevin; Dowell, Cheryl; Hone, Arik J.; Morgenstern, David; Chua, Victor M.; Ramiro, Iris Bea L.; Imperial, Julita S.; Leavitt, Lee S.; Phan, Jasmine; Fisher, Fernando A.; Watkins, Maren; Raghuraman, Shrinivasan; Tun, Jortan O.; Ueberheide, Beatrix M.; McIntosh, J. Michael; Vasconcelos, Vitor; Olivera, Baldomero M.; Gajewiak, Joanna (MDPI, 2024-02-29)The venom of cone snails has been proven to be a rich source of bioactive peptides that target a variety of ion channels and receptors. α-Conotoxins (αCtx) interact with nicotinic acetylcholine receptors (nAChRs) and are powerful tools for investigating the structure and function of the various nAChR subtypes. By studying how conotoxins interact with nAChRs, we can improve our understanding of these receptors, leading to new insights into neurological diseases associated with nAChRs. Here, we describe the discovery and characterization of a novel conotoxin from Conus ateralbus, αCtx-AtIA, which has an amino acid sequence homologous to the well-described αCtx-PeIA, but with a different selectivity profile towards nAChRs. We tested the synthetic αCtx-AtIA using the calcium imaging-based Constellation Pharmacology assay on mouse DRG neurons and found that αCtx-AtIA significantly inhibited ACh-induced calcium influx in the presence of an α7 positive allosteric modulator, PNU-120596 (PNU). However, αCtx-AtIA did not display any activity in the absence of PNU. These findings were further validated using two-electrode voltage clamp electrophysiology performed on oocytes overexpressing mouse α3β4, α6/α3β4 and α7 nAChRs subtypes. We observed that αCtx-AtIA displayed no or low potency in blocking α3β4 and α6/α3β4 receptors, respectively, but improved potency and selectivity to block α7 nAChRs when compared with αCtx-PeIA. Through the synthesis of two additional analogs of αCtx-AtIA and subsequent characterization using Constellation Pharmacology, we were able to identify residue Trp18 as a major contributor to the activity of the peptide.
- Total polyphenol content of tropical marine and coastal flora: Potentials for food and nutraceutical applicationsNarvarte, Bienson Ceasar V.; Genovia, Tom Gerald T.; Hinaloc, Lourie Ann R.; Gonzaga, Shienna Mae C.; Tabonda-Nabor, April Mae; Palecpec, Flora Maye R.; Dayao, Helen M.; Roleda, Michael Y. (Springer, 2023-07-08)The marine environment is abundant in natural products that are beneficial to humans. Among these compounds are the polyphenols produced by marine flora as secondary metabolites and used as a defense against stressful environmental conditions. Accordingly, recent pharmacological and biomedical studies showed that polyphenols from marine and coastal floras have several important bioactivities including antioxidant property. In this study, we measured the total polyphenol content (TPC) of 75 species of marine-associated flora. The TPC of their methanolic extracts was measured spectrophotometrically using the Folin-Ciocalteu assay and was expressed both as mg phloroglucinol equivalent per g of dry weight (mg PGE g−1 DW) and as mg gallic acid equivalent per g dry weight (mg GAE g−1 DW). The TPC values are higher when expressed in terms of GAE compared to PGE. Also, the mean TPC of tracheopytes (229 ± 43.0 mg PGE g−1 DW) was higher compared to the mean TPC of macroalgae (69.4 ± 9.59 mg PGE g−1 DW). For macroalgae, ochrophytes (97.9 ± 22.7 mg PGE g−1 DW) had the highest mean TPC followed by chlorophytes (80.0 ± 20.5 mg PGE g−1 DW) and rhodophytes (49.5 ± 8.60 mg PGE g−1 DW). Moreover, our study also showed that TPC varied between young and mature tissues, among different color morphotypes and different parts of the plants. Although the concentrations of total polyphenols varied among species, ages, strains and parts of the plant, our study showed that marine and coastal floras are rich sources of polyphenols that could be further examined for their biological activities and other applications in food industry.
- Genomics and metabolomics-based assessment of the biosynthetic potential of the sponge-associated microorganism Streptomyces cacaoi strain R2A-843A from the PhilippinesMalto, Zabrina Bernice L.; Reyes, Joeriggo M.; Lo, Bernard Isaiah; Davis, Kevin Bossie S.; Concepcion, Gisela; Salvador-Reyes, Lilibeth A. (Philippine-American Academy of Science and Engineering, 2023-10-20)The biosynthetic machinery of the sponge-associated Streptomyces cacaoi strain R2A-843A was assessed using a combined genomics and metabolomics approach. Whole genome sequencing and molecular networking showed the high biosynthetic potential of this actinomycete. A significant proportion of the genome is dedicated to secondary metabolite production, with biosynthetic gene clusters for nonribosomal peptides, polyketides, and terpenes being the most represented. Seven cyclic pentapeptides, including a putative new analogue, and a glycosylated lanthipeptide were identified using HRMS and untargeted MS/MS analysis. To validate our genome and metabolome analysis, we undertook a mass spectrometry-guided purification and confirmed the production of the known peptides BE-18257A (1) and BE-18257B (2). The production of 1 and 2 and the growth of the microorganism were monitored for eight days. Compound 2 was produced at a higher concentration, starting at 48 h post-incubation. Both compounds were noncytotoxic against colorectal and breast cancer cell lines.
- 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.
- Genome mining of a novel marine sponge symbiont Nocardia sp. BML-15-R-026U reveals high biosynthetic potential for secondary metabolites, including a non-ribosomal peptide and a polyketide of high noveltyGloria, Paul Christian; Romines, Elaine; Punzalan, Marc Jeremie; Florece, Christine Marie; Cadorna, Kreighton; Salvador-Reyes, Lilibeth; Lluisma, Arturo (Philippine-American Academy of Science and Engineering, 2023-11-28)Antibiotic and drug resistance poses serious global public health threats, leading to substantial infections and fatalities annually. Addressing these issues requires the discovery of novel bioactive compounds and a faster and more cost-effective discovery process. However, traditional approaches, which require isolation and multi-step purification of compounds from organisms and running of initial assays, suffer from serious limitations such as the need for substantial amounts of biological material and high rates of compound rediscoveries. Because the biosynthetic capabilities of organisms are encoded in their genomes, genome mining provides a promising solution that would complement traditional approaches. This study conducted long-read whole genome sequencing on a marine sponge symbiont, Nocardia sp. BML-15-R-026U, to explore its genomic repertoire of secondary metabolite-encoding Biosynthetic Gene Clusters (BGCs). A four-contig genome assembly was generated for this isolate with a high degree of completeness and an estimated genome size of 4.84 Mbp. Its genome displays remarkable biosynthetic potential by containing at least 34 distinct secondary metabolite BGCs, predominantly Non-Ribosomal Peptide Synthetase (NRPS) and Polyketide Synthase (PKS) systems capable of producing novel chemical structures. Further analysis was focused on two genomic regions. In region 3.10, the study predicted a BGC for a novel, serine-rich non-ribosomal peptide with a predicted molecular weight of 2754 g/mol. Region 3.12 contained an iterative type-I PKS BGC, suggesting the potential synthesis of a polyketide compound with oxidoreductase-inhibiting properties. This study highlights genome mining as a productive early-phase approach for identifying promising drug leads and has identified the most promising candidates among this isolate’s BGCs for experimental validation.
- Physicochemical and biochemical characterization of collagen from Stichopus cf. horrens tissues for use as stimuli-responsive thin filmsSisican, Kim Marie D.; Torreno, Vicenzo Paolo M.; Yu, Eizadora T.; Conato, Marlon T. (American Chemical Society, 2023-09-20)The mutable collagenous tissue (MCT) of sea cucumber, with its ability to rapidly change its stiffness and extensibility in response to different environmental stress conditions, serves as inspiration for the design of new smart functional biomaterials. Collagen, extracted from the body wall of Stichopus cf. horrens, a species commonly found in the Philippines, was characterized for its suitability as stimuli-responsive films. Protein BLAST search showed the presence of sequences commonly found in type VII and IX collagen, suggesting that Stichopus horrens collagen is heterotypic. The maximum transition temperature recorded was 56.0 ± 2 °C, which is higher than those of other known sources of marine collagen. This suggests that S. horrens collagen has better thermal stability and durability. Collagen-based thin films were then prepared, and atomic force microscopy (AFM) imaging showed the visible collagen network comprising the films. The thin films were subjected to thermomechanical analysis with degradation starting at >175 °C. At 100–150 °C, the collagen-based films apparently lose their translucency due to the removal of moisture. Upon exposure to ambient temperature, instead of degrading, the films were able to revert to the original state due to the readsorption of moisture. This study is a demonstration of a smart biomaterial developed from S. cf. horrens collagen with potential applications in food, pharmaceutical, biomedical, and other collagen-based research.
- Total synthesis and bioactivity evaluation of hydrophobic microcionamide‐inspired peptidesInocentes, Carl Rogel V.; Salvador‐Reyes, Lilibeth A.; Villaraza, Aaron Joseph L. (Wiley, 2023-01)In this report, we describe the facile synthesis of four microcionamide-inspired peptides where the atypical 2-phenylethylenamine (2-PEA) functional group in the marine natural product, microcionamide A, was replaced with a similarly-aromatic but more easily incorporated tryptophan (Trp) residue. Compounds 1–4 were synthesized using a standard Fmoc-based solid-phase synthesis strategy followed by iodine-mediated on-resin cyclization for disulfide-bridged compounds 1–3. Compound 1 showed antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa, with minimum inhibitory concentrations (MICs) of 9.1 μM and 15 μM, respectively. The inactivity of alanine analogs 2–4 against these pathogens suggests that the N-terminal Val, the cyclic scaffold, the contiguous Ile residues, and consequently, the hydrophobicity of compound 1 are essential for antibacterial activity. Compound 1 also favorably exhibited minimal cytotoxicity against normal mammalian cell lines. In summary, we have synthesized an analog of microcionamide A where replacement of the 2-PEA moiety with a Trp residue retained the antibacterial activity and with favorably low cytotoxicity.
- BFAR Administrative Circular No. 256: Series of 2015. Declaring malachite green and gentian violet as health hazards and prohibiting their use in food fish production and trade.(Bureau of Fisheries and Aquatic Resources, 2015-02-12)