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Biology subjects

Mishra, I.

Publications and source records attributed to Mishra, I..

3 recordsLinked to original sources

Deep Video Analysis for Bacteria Genotype Prediction

Genetic modification of microbes is central to many biotechnology fields, such as industrial microbiology, bioproduction, and drug discovery. Understanding how specific genetic modifications influence observable bacterial behaviors is crucial for advancing these fields. In this study, we propose a supervised model to classify bacteria harboring single gene modifications to draw connections between phenotype and genotype. In particular, we demonstrate that the spatiotemporal patterns of Vibrio cholerae growth, recorded in terms of low-resolution bright-field microscopy videos, are highly predictive of the genotype class. Additionally, we introduce a weakly supervised approach to identify key moments in culture growth that significantly contribute to prediction accuracy. By focusing on the temporal expressions of bacterial behavior, our findings offer valuable insights into the underlying mechanisms and developmental stages by which specific genes control observable phenotypes. This research opens new avenues for automating the analysis of phenotypes, with potential applications for drug discovery, disease management, etc. Furthermore, this work highlights the potential of using machine learning techniques to explore the functional roles of specific genes using a low-resolution light microscope.

bioinformatics↗

Unveiling Mechanistic and Structural Insights of EstS1 Esterase: A Potent Broad-Spectrum Phthalate Diester Degrading Enzyme

The ubiquitous presence of plastics and plasticizers around the globe has raised an alarming condition. Phthalate diesters are high-priority pollutants that mimic natural hormones and act as endocrine disruptors upon entering living systems. While certain bacterial esterases have been identified for their role in phthalate diester degradation, their structural and mechanistic characteristics remain largely unexplored. A thermostable and pH-tolerant EstS1 esterase from Sulfobacillus acidophilus catalyzes the conversion of low molecular weight phthalate diesters to monoesters. This study highlights the unique potential of EstS1 to degrade high molecular weight bis(2-ethylhexyl) phthalate (DEHP) by employing biophysical and biochemical approaches along with in-depth structural analysis utilizing high-resolution crystal structures in both apo and complex forms, with various substrates, products, and their analogs to elucidate mechanistic details. The catalytic tunnel mediating entry and exit of the substrate and product, respectively, centralized the Ser-His-Asp triad performing catalysis by bi-bi ping-pong mechanism, forming a tetrahedral intermediate. Additionally, structural analysis of the polypropylene analog jeffamine with EstS1 revealed effective covalent binding, demonstrating its multifunctional capability. Mutation analysis showed that the Met207Ala mutation abolished DEHP binding at the active site, confirming its essential role in supporting catalysis. These findings underscore the potential of EstS1 as a key tool for advancing technologies aimed at phthalate diesters biodegradation.

biophysics↗

Asprosin Neutralizing Antibodies as a Treatment for Metabolic Syndrome

Recently, we discovered a new glucogenic and centrally-acting orexigenic hormone - asprosin. Asprosin is elevated in metabolic syndrome (MS) patients, and importantly, its genetic loss results in reduced appetite, leanness and robust insulin sensitivity, leading to protection from MS. Here we demonstrate that anti-asprosin monoclonal antibodies (mAbs) are a dual-effect pharmacologic therapy that targets the two key pillars of MS - over-nutrition and the blood glucose burden. Anti-asprosin mAbs from three distinct species lowered appetite and body weight, and improved blood glucose in a dose-dependent and epitope-agnostic fashion in three independent MS mouse models, with an IC50 of [~]1.5 mg/kg. In addition, mAb treatment ameliorated MS associated dyslipidemia and hepatic dysfunction. The mAbs displayed half-life of over 3 days in vivo, with equilibrium dissociation-constants in picomolar to low nanomolar range. This evidence paves the way for further development towards an investigational new drug application and subsequent human trials for treatment of MS, a defining physical ailment of our time.

physiology↗