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Biology subjects

Shagun, S.

Publications and source records attributed to Shagun, S..

3 recordsLinked to original sources

Identification of conserved age-associated aggregation-prone proteins for natural molecule targeting during aging in Caenorhabditis elegans

Aging is associated with proteome remodelling and progressive accumulation of insoluble proteins. Identifying age-enriched proteins that undergo aggregation and evaluating compounds capable of modulating their behaviour may provide insights into interventions that promote healthy aging. Here, we report a proteome-guided strategy to identify age-associated aggregation-prone proteins and evaluate phytochemicals targeting conserved proteins in Caenorhabditis elegans. We identified proteins whose abundance increased more than four-fold in aged worms compared with young worms, many of which also accumulated in the age-associated insoluble proteome, and subsequently identified their human orthologs for comparative analysis. Based on biological relevance, structural conservation, and availability of high-confidence structural models, glutamine-fructose-6-phosphate aminotransferase-2 (GFAT-2) was selected for molecular docking. Screening of fifteen phytochemicals against C. elegans GFAT-2 and its human ortholog GFPT1 identified quercetin as the strongest predicted binder, exhibiting conserved interactions with both proteins. However, treatment of worms with quercetin did not significantly alter global protein insolubility during aging. This may reflect its ability to modulate inappropriate protein-protein interactions without substantially affecting the overall aggregation burden. These findings underscore the need for experimental validation of favourable in silico docking predictions. More broadly, this study provides a proteome-guided framework for prioritizing age-associated aggregation-prone proteins as candidate therapeutic targets for preserving proteostasis during aging.

biochemistry↗

Genome-scale metabolic model guided metabolic flux analysis in the endophyte Alternaria burnsii NCIM1409

Camptothecin (CPT), a potent anticancer alkaloid, is traditionally derived from plants like Camptotheca acuminata and Nothapodytes nimmoniana, but sustainable production remains challenging. This study explores the metabolic network of the fungal endophyte Alternaria burnsii NCIM1409, known for camptothecin production, using genome sequencing, genome scale metabolic modeling, and 13C-based pathway mapping. A genome-scale metabolic model (AltGEM iDD1552) was reconstructed, comprising 2188 reactions, 2148 metabolites, and 1552 genes, along with manual curation to include camptothecin biosynthesis pathways. Flux balance analysis identified key enzymatic targets, including secologanin synthase and tryptophan decarboxylase, for enhancing CPT production. Further, metabolic analysis of A. burnsii subjected to 20%[U-13C6] glucose or 99% [1-13C] glucose revealed active glycolysis, the pentose phosphate pathway, and the TCA cycle. This integrative approach provides insights into A. burnsiis metabolic capabilities and highlights strategies for optimizing camptothecin biosynthesis, offering a foundation for sustainable production methods.

systems biology↗

Mass spectrometry and NMR spectroscopy profiles of red and pink Rhododendron flower petals establish them as rich sources of bioactive secondary metabolites

Rhododendron petals are considered high-value owing to their commercial utility, national/state flower status in certain countries, and bioactive potential from recent studies. Profiling and quantitative analysis of the bioactive metabolites would evaluate if they can be natural sources. This study is focused on comprehensive profiling of secondary metabolites in the petals of Red and Pink Rhododendron flowers (R. arboreum and R. campanulatum) using Mass Spectrometry (GC-MS, LC-MS/MS) and Proton-Nuclear Magnetic Resonance (1H-NMR) Spectroscopy. The profiling highlighted the presence of secondary metabolites belonging to phenolic acids and flavonoids. Specifically, the flowers are rich in promising bioactive molecules such as quinic acid, chlorogenic acid (3-O-caffeoyl quinic acid), protocatechuic acid, coumaroyl quinic acids, catechin, epigallocatechin, and shikimic acid. The profiles are correlated with the metabolic pathways which reflected the activity of shikimic acid, phenolic acid and flavonoid biosynthetic pathways. These metabolites are well reported for their bioactive potential as anti-oxidative, anti-viral, anti-cancerous, anti-diabetic, anti-inflammatory, etc. While the quantitative and multivariate analysis showed variations in the levels of phenolic acids and flavonoids, it is established that red and pink Rhododendron flower petals are a rich source of bioactive phytochemicals of interest to the phytochemical Industry.

plant biology↗