Biology subjects

Bhat, S. G.

Publications and source records attributed to Bhat, S. G..

5 recordsLinked to original sources

bioRxiv2026

Large-scale production of melanin nanoparticles from Pseudomonas stutzeri strain BTCZ109

Past few decades witnessed a boom in pharmaceutical and bioproduct industry with the help of bioprocess technology. Industrially important bioproducts can be produced in large scale for commercialization with the help of fermenters. Here in, pharmaceutically valuable bioproduct melanin, synthesized from Pseudomonas stutzeri strain BTC109 by using two different sized bioreactors. Under controlled conditions the bacteria were allowed to synthesis melanin nanoparticles. The important parameters to be monitored here are pH, dissolved oxygen, agitation, aeration, melanin production and cell biomass concentration. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=163 SRC="FIGDIR/small/737634v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@1cc9ca0org.highwire.dtl.DTLVardef@3eeb0borg.highwire.dtl.DTLVardef@b95bd3org.highwire.dtl.DTLVardef@13b8860_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIPharmaceutical and bioproduct development industries witnessed a shoot up due to bioprocess technology. C_LIO_LIIndustrially important bioproduct like melanin can be produced in large scale with the help of industrial fermentation technology. C_LIO_LIThe product thus obtained was found to be nano sized and it can be commercialized. C_LI

microbiology↗

bioRxiv2026

Optimization of process parameters for melanin nanoparticles synthesised from Pseudomonas stutzeri (BTCZ 109) using OFAT method and its anticancer property evaluation

Melanins are biological macromolecule with immense functionality synthesised by a wide spectrum of living organism. It is mainly synthesised by the oxidative polymerization of indolic and phenolic compounds through several enzymatic process. It has wide spread application in agriculture, cosmetic and therapeutic industry due to its various properties including antioxidation ability, UV protection efficiency and anticancer activity. Because of this wide range of application in different sectors, large scale production and commercialization attains enormous consideration. The present study deals with the effect of 12 different process parameters on melanin production viz., production media, incubation time, inoculum concentration, pH, temperature, agitation, carbon source, phosphate and magnesium source, CuSO4.5H2O, sodium chloride and L-tyrosine on melanin production by Pseudomonas stutzeri strain BTCZ 109 obtained from Arabian sea sediments was evaluated. After optimizing the important process parameters, the bacteria showed about [~] 4.65 fold increase in melanin production compared to unoptimized cultural conditions. The melanin optimized through this method was found to be nano sized. The Nano sized DOPA melanin in treating Skin cancer cell line SK ML28 which showed a dose-dependent activity with an IC50 value of 164 g/mL. All these results highlight the therapeutic efficiency of DOPA melanin Nano particle as promising bioactive molecule. HighlightsO_LIProcess parameter optimization for large scale production of Nano-melanin obtained from Pseudomonas stutzeri strain BTCZ 109 through one-factor-at-a-time method. C_LIO_LIOptimization of 12 different process parameters were carried out which led to an increase in yield of [~] 4.65 fold compared to unoptimized culture conditions. C_LIO_LIIts efficiency in treating skin cancer cell line SK ML28 was also detected. C_LI

microbiology↗

bioRxiv2025

Billi: Provably Accurate and Scalable Bubble Detection in Pangenome Graphs

A key application of pangenome graphs is the characterization of small and large genomic variants represented as bubbles within the graph. Although bubbles have been extensively studied in directed graphs in the context of genome assembly, there remains a need for a rigorous definition and systematic analysis of bubbles in bidirected graphs, which is the predominant data structure used to represent pangenomes. We show that existing bubble definitions for bidirected graphs do not fully meet the requirements for representing genetic sites and alleles; in particular, overlapping bubbles may not exhibit strict nesting. To address this, we introduce a new sub-graph abstraction called panbubble and prove that it satisfies the desired structural properties for variant characterization. We then present an exact algorithm with runtime [O] (|V |2(|V | + |E|)) for detecting all panbubbles in a bidirected graph G = (V, E). In addition, we propose a heuristic algorithm that produces identical output as the exact algorithm in practice and scales to large graphs, including both the first and second releases of the Human Pangenome Reference Consortium (HPRC). We implemented our algorithms in the tool Billi (github.com/at-cg/billi). On our largest dataset, Billi is more than 15x faster and uses over 5x less memory than VG.

bioinformatics↗

bioRxiv2022

dnaE2 expression promotes genetic diversity and bacterial persistence in mycobacterial biofilms

The complex cellular architecture and the microenvironments within the biofilm give rise to a population that is both physiologically and genetically heterogeneous. Transcriptome analysis of Mycobacterium smegmatis in biofilm culture and its transition phase into planktonic growth was performed to identify the genetic basis of heterogeneity in the biofilm. While there was an increase in the expression of mycobacterial mutasome consisting of dnaE2, imuA, and imuB in the biofilm, the mutation burden was less compared to the planktonic culture. Deletion of dnaE2 causes lower mutation frequency and bacterial fitness in comparison to the parental strain in biofilm culture. The expression of dnaE2 contributes to a slower bacterial growth rate, potentially promoting persister formation. Our study uncovers the multiple benefits of dnaE2 expression in biofilm such as increasing genetic diversity and reducing growth rate; both of which are necessary for mycobacterial survival and adaptation.

microbiology↗

bioRxiv2021

Ecological interactions: Patterns of host utilization by tropical butterflies

Structural complexity of ecological networks facilitate the functional robustness of natural ecosystems. Threatened by the human actions such as habitat destruction and climate change, species may be more or less prone to ecological perturbations depending on the nature of their interactions. We examined the host network of tropical butterflies from the Indian region to see their level of interconnectedness. We manually curated larval host utilization data for 1053 butterflies of India. About 98.8% of species that occur pan-India and 90.6% of species exclusive to the Western Ghats had known hosts whereas it was only 25.9% for species exclusive to north-east India. There were 2589 unique butterfly-host interactions comprising 519 butterfly species and their 1091 known hosts. However, nearly 30% of the species had only single hosts. The Fabaceae and Poaceae were the key host families that accounted for 32.8% of the interactions. There were clear host preferences and monocots hosted disproportionately more butterfly species and interactions. Vanessa cardui had at least 39 known hosts while Ochlandra travancorica supported 19 butterfly species. There were 2693 species-pairs and 4226 interactions among 469 butterflies due to shared hosts. Many butterfly species that have relatively few/unique hosts might be vulnerable in the context of habitat destruction and climate change. This work has great relevance to the ecology and conservation of butterflies in India.

ecology↗