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Biology subjects

Deobagkar, D. D.

Publications and source records attributed to Deobagkar, D. D..

5 recordsLinked to original sources

Drosophila melanogaster as a model host to study arbovirus vector interaction

Arboviruses cause the most devastating diseases in humans and animals worldwide. Several hundred arbovirus are transmitted by mosquitoes, sand flies or ticks and are responsible for more than million deaths annually. Development of a model system is essential to extrapolate the molecular events occurring during infection in the human and mosquito host. Virus overlay protein binding assay (VOPBA) combined with MALDI TOF/TOF MS revealed that Dengue-2 virus (DENV-2) exploits similar protein molecules in Drosophila melanogaster and Aedes aegypti for its infection. Furthermore, the virus susceptibility studies revealed that DENV-2 could propagate in D. melanogaster, and DENV-2 produced in fruit fly is equally infectious to D. melanogaster and Ae. aegypti. Additionally, real time PCR analysis revealed that RNAi coupled with JAK-STAT and Toll pathway constitutes an effector mechanism to control the DENV-2 infection in flies. These observations point out that D. melanogaster harbors all necessary machineries to support the growth of arboviruses. With the availability of well-established techniques for genetic and developmental manipulations, D. melanogaster, offers itself as the potential model system for the study of arbovirus-vector interactions.

zoology↗

Isolation, identification and functional characterization of cultivable bacteria from Arabian Sea and Bay of Bengal water samples reveals high diversity

The oxygen minimum zone of the Arabian Sea (AS) and Bay of Bengal (BOB) is rich in organic matter and is an unusual niche. Bacteria present in the oceanic water play an important role in ecology since they are responsible for decomposing, mineralizing of organic matter and in elemental cycling like nitrogen, sulfur, phosphate. This study focuses on culturing bacteria from oxygen minimum zones (OMZ) and non-OMZ regions and their phylogenetic as well as the functional characterization. Genotypic characterization of the isolates using amplified rDNA based 16SrRNA sequencing grouped them into various phylogenetic groups such as alpha-proteobacteria, gamma-proteobacteria and unaffiliated bacteria. The cultivable bacterial assemblages encountered belonged to the genus Halomonas, Marinobacter, Idiomarina, Pshyctobacter and Pseudoalteromonas. Among the enzymatic activities, carbohydrate utilization activity was most predominant (100%) and microorganisms possessed amylase, cellulase, xylanase and chitinase. A large proportion of these bacteria (60%) were observed to be hydrocarbon consuming and many were resistant to ampicillin, chloramphenicol, kanamycin and streptomycin. The high diversity and high percentage of extracellular hydrolytic enzyme activities along with hydrocarbon degradation activity of the culturable bacteria reflects their important ecological role in oceanic biogeochemical cycling. Further assessment confirmed the presence of nitrogen reduction capability in these cultivable bacteria which highlights their importance in oceanic geochemical cycling.

microbiology↗

Genome-wide comparison of DNA methylation between life cycle stages of Drosophila melanogaster using high-throughput sequencing techniques.

Drosophila melanogaster undergoes holometabolous development, has very low levels of DNA methylation, and is known to possess a single known methyltransferase, dDNMT2. This study compares the DNA methylation patterns between the two life cycle stages of D. melanogaster using a combination of DNA immunoprecipitation and high throughput sequencing techniques. Our results indicate, a change in the chromosomal distribution of the sparse DNA methylation concerning genes and natural transposable elements between in the embryo and the adult stages of D. melanogaster. The differentially methylated regions localised on genes involved in the regulation of cell cycle processes of mitotic cell divisions and chromosomal segregation. dDNMT2 knockout flies exhibited altered patterns of DNA methylation. The observed differences in DNA methylation were in genes involved in cellular communication and cytoskeletal functions. The variation in DNA methylation between the two life cycle stages is indicative that it could have a role in regulatory processes during development and, dDNMT2 may have a role as a co-factor for the hitherto undiscovered DNA methyltransferase in D. melanogaster.

genomics↗

Metagenomic analysis of soil samples collected from estuarine mangroves of Arabian Sea reveals rich microbiota and high numbers of sulphate reducing bacteria accompanied with methanogen bacteria.

This study reports the analyses of the microbiome of the estuarine soil of mangroves of the Arabian Sea. Mangroves soil samples were collected from 12 locations of Arabian Sea coast of Maharashtra, India. 16S rRNA gene V3-V4 region amplicon sequencing was performed using the Miseq Illumina platform to identify the microbial communities present in the mangroves ecosystem. The metagenomics analysis provided an insight into the abundance, diversity and spatial variations in the mangrove microbial communities in relation to physico-chemical parameters and revealed that Proteobacteria, Flavobacteria and Planctomycetes are abundant in mangroves system. The differences in bacterial abundance, composition and diversity can partly be attributed to the physico-chemical characteristics of the samples, geographical location and anthropogenic activities in the locality. High numbers of sulphate reducing bacteria accompanied with methanogen bacteria were characteristic of Indian mangroves. The results obtained in the current study indicate rich species diversity and add valuable insights about the diversity of microbial communities of the mangroves in Maharashtra along the west coast of India and can provide better information for effective measures for conservation of mangroves. GIS based prediction suggest that the sulphur utilizing communities are under threat from anthropogenic activities and may decline in future if immediate measures are not implemented.

microbiology↗

Microbial diversity of the Arabian Sea in the Oxygen minimum zones by metagenomics approach

Large oxygen depleted areas known as oxygen minimum zones (OMZ) have been observed in the Arabian Sea and recent reports indicate that these areas are expanding at an alarming rate. In marine waters, oxygen depletion may also be related to global warming and the temperature rise, acidification and deoxygenation can lead to major consequences wherein the plants, fish and other biota will struggle to survive in the ecosystem.\n\nThe current study has identified the microbial community structure using NGS based metagenomics analysis in the water samples collected at different depth from the oxygen depleted and non-OMZ areas of Arabian Sea. Environmental variables such as depth, site of collection and oxygen concentration appeared to influence the species richness and evenness among microbial communities in these locations. Our observations clearly indicate that population dynamics of microbes consisting of nitrate reducers accompanied by sulphate reducers and sulphur oxidizers participate in the interconnected geochemical cycles of the OMZ areas. In addition to providing baseline data related to the diversity and microbial community dynamics in oxygen-depleted water in the OMZ; such analysis can provide insight into processes regulating productivity and ecological community structure of the ocean.

microbiology↗