Iyer, S. M. | bioRxiv Science

bioRxiv2022

Neuroprotective potential of an Ayurvedic compound "Ras Sindoor" on Drosophila melanogaster model of Parkinson's disease

Parkinsons Disease (PD) is the second most common neurodegenerative disease affecting 1-2% of the global population with no cure to date. PD is characterized by accumulation of Lewy Bodies (LBs), which are caused due to aggregation of incorrectly folded -Synuclein, (SNCA). Another form of PD manifestation is characterized by loss of function of parkin, which encodes an E3 ubiquitin ligase. Despite extensive research, the cause for onset and progression of PD remains unknown and current therapeutics mainly help manage the disease. An alternative line of treatment can be useful. In this study, we have employed two different genetic models of Drosophila to screen for Ayurvedic compounds and found an Ayurvedic mercury based organo-metallic drug Ras-Sindoor has neuroprotective function. Our data indicate that characteristic locomotory dysfunction phenotype of PD is restored upon administration of the compound. Interestingly, RS fed flies also exhibit reduced transcript levels of initiator caspase dronc, which possibly prevents cell death in dopaminergic neurons. Additionally, RS fed PD model flies exhibit an enhanced life span. Our studies emphasize beneficial use of traditional Ayurvedic compounds as a holistic cure for PD like multifactorial diseases.

neuroscience↗

bioRxiv2020

Improving cell-free glycoprotein synthesis by characterizing and enriching native membrane vesicles

Cell-free gene expression (CFE) systems from crude cellular extracts have attracted much attention for accelerating the design of cellular function, on-demand biomanufacturing, portable diagnostics, and educational kits. Many essential biological processes that could endow CFE systems with desired functions, such as protein glycosylation, rely on the activity of membrane-bound components. However, without the use of synthetic membrane mimics, activating membrane-dependent functionality in bacterial CFE systems remains largely unstudied. Here, we address this gap by characterizing native, cell-derived membrane vesicles in Escherichia coli-based CFE extracts and describing methods to enrich vesicles with heterologous, membranebound machinery. We first use nanocharacterization techniques to show that lipid vesicles in CFE extracts are tens to hundreds of nanometers across, and on the order of ~3x1012 particles/mL. We then determine how extract processing methods, such as post-lysis centrifugation, can be used to modulate concentrations of membrane vesicles in CFE systems. By tuning these methods, we show that increasing the number of vesicle particles to ~7x1012 particles/mL can be used to increase concentrations of heterologous membrane protein cargo expressed prior to lysis. Finally, we apply our methods to enrich membrane-bound oligosaccharyltransferases and lipid-linked oligosaccharides for improving N-linked and O-linked glycoprotein synthesis. We anticipate that our findings will facilitate in vitro gene expression systems that require membrane-dependent activities and open new opportunities in glycoengineering.

synthetic biology↗