Biology subjects

Maitra, D.

Publications and source records attributed to Maitra, D..

3 recordsLinked to original sources

bioRxiv2025

A detailed study Biofilm forming Polyextremophilic Firmicutes from the Himalayas and exploration of their plant growth promoting potential.

Polyextremophily has been an intriguing point of interest among the scientists, a phenomenon in which organisms can thrive in combinations of multiple extreme conditions. In the foreseeable future, climatic conditions are predicted to change, and agriculture is bound to suffer with these changes in the environment. The situation necessitates some solutions that can ensure agricultural sustainability, in the changed, harsh environmental conditions without more toxic chemical intrusions in the agricultural fields. The bacterial strains Brevibacillus parabrevis BRAM_Y3 and Mesobacillus subterraneous BRAM_Y2 in this study, isolated from the waters of Yamunotri showed incredible properties of Polyextremophily like tolerance to not only temperatures as high as 70{degrees}C, pH range (4-10), saline, drought, UV and heavy metals such as mercury, iron, silver and arsenic but also their two-dimensional and three-dimensional combinations. The elevated levels of biofilm formation when subjected to stress revealed their property of using biofilm as their shield against harsh conditions. Furthermore, they were studied for their plant growth promotion like nutrient sequestration (N, P, K, plant hormone production etc.) biocontrol properties (cell wall degrading enzymes, siderophores, VOCs etc.) and the ability to confer abiotic stress resistance (ACC Deaminase) to plants. The in-vivo experiments conducted on Zea mays. L yielded conclusive and promising results. The use of these polyextremophiles for agriculture in harsh environments may serve as a solution for the global warming mediated climate and environmental changes.

microbiology↗

bioRxiv2021

Acitretin mitigates uroporphyrin-induced bone defects in congenital erythropoietic porphyria models

Congenital erythropoietic porphyria (CEP) is a rare genetic disorder leading to accumulation of uro/coproporphyrin-I in tissues due to inhibition of uroporphyrinogen-III synthase. Clinical manifestations of CEP include bone fragility, severe photosensitivity and photomutilation. Currently there is no specific treatment for CEP, except bone marrow transplantation, and there is an unmet need for treating this orphan disease. Fluorescent porphyrins cause protein aggregation, which led us to hypothesize that uroporphyrin-I accumulation leads to protein aggregation and CEP-related bone phenotype. We developed a zebrafish model that phenocopies features of CEP. As in human patients, uroporphyrin-I accumulated in the bones of zebrafish, leading to impaired bone development. Furthermore, in an osteoblast-like cell line, uroporphyrin-I decreased mineralization, aggregated bone matrix proteins, activated endoplasmic reticulum stress and disrupted autophagy. Using high-throughput drug screening, we identified acitretin, a second-generation retinoid, and showed that it reduced uroporphyrin-I accumulation and its deleterious effects on bones. Our findings provide a new CEP experimental model and a potential repurposed therapeutic.

pathology↗

bioRxiv2021

Protoporphyrin-IX nanostructures modulate their protein aggregation ability via differential oxidation and protein binding

Porphyrias are caused by genetic defects in the heme biosynthetic pathway and are associated with accumulation of high levels of porphyrins that become cytotoxic. Porphyrins, due to their amphipathic nature, spontaneously associate into different nanostructures but very little is known about the effect of porphyrin speciation on the cytotoxic effects of porphyrins. Previously we demonstrated the unique ability of fluorescent biological porphyrins, including protoporphyrin IX (PP-IX), to cause organelle selective protein aggregation, which we posit to be a major mechanism by which porphyrins exerts their cytotoxic effect. Herein, we tested the hypothesis that PP-IX-mediated protein aggregation is modulated by different PP-IX nanostructures via a mechanism that depends on their oxidizing potential and protein binding ability. We demonstrate that PP-IX nanostructure formation is reversible in nature, and that nanostructure size modulates consequent protein oxidation and aggregation potential. We also show that albumin, the most abundant serum protein, preferentially binds PP-IX dimers and enhances their oxidizing ability. Additionally, extracellular albumin protects from intracellular porphyrinogenic stress and protein aggregation by acting as a PP-IX sponge. This work highlights the importance of PP-IX speciation in the context of the porphyrias, and offers insights into potential novel therapeutic approaches.

biochemistry↗