Sediment Plasmidome of the Gulfs of Kathiawar Peninsula and Arabian Sea: Insights Gained from Metagenomics Data.

Plasmidomes have become the research area of interest for ecologists exploring bacteria rich ecosystems. Marine environments are among such niche that host a huge number of microbes and have a complex environment which pose the need to study these bacterial indicators of horizontal gene transfer events for survival and stability. The plasmid content of the metagenomics data from 8 sediment samples of the Gulfs of Kathiawar and an open Arabian Sea sample was screened. The reads corresponding to hits against the plasmid database were assembled and studied for diversity using Kraken and functional content using MG-RAST. The sequences were also checked for resistome and virulence factors. The replicon hosts were overall dominated by Proteobacteria, Firmicutes, and Actinobacteria while red algae specific to the Kutch samples. The genes encoded were dominant in the flagella motility and type VI secretion systems. Overall, results from the study confirmed that the plasmids encoded traits for metal, antibiotic, and phage resistance along with virulence systems, and these would be conferring benefit to the hosts. The study throws insights into the environmental role of the plasmidome in adaptation of the microbes in the studied sites to the environmental stresses.

Viral footprints across Gulfs of Kathiawar Peninsula and Arabian Sea: Unraveled from pelagic sediment metagenomic data.

Marine biosphere is one of the largest, diverse and dynamic system hosting numerous of microorganisms. Viruses being the most abundant under explored lifeforms in ocean, represent a reservoir of great genetic diversity. We report the metagenomic insights on the viral communities in the deep sediments of the two Gulfs of Gujarat i.e. Gulf of Khambhat and Gulf of Kutch, with one sample from Arabian Sea, treated as open sea control. The viral reads were filtered from the whole dataset, assembled and studied for viral diversity, which was visualized by Pavian. The sequences were checked for the viral abundance, diversity and functionality. The resulting viral taxonomic classification contained 6 orders, 8 families and 47 genera. The results revealed that the phages infecting Cyanobacterium, Bacillus and Vibrio dominated the sediments. Further, it was observed that majority of viral sequences belonged to double-stranded DNA phages. The present study attempts to provide a primary insight of the viral signals and potential genetic content in the Gulfs of Kathiawar.

Evolutionary and Antigenic Profiling of the Tendentious D614G Mutation of SARS-CoV-2 in Gujarat, India.

Humankind has suffered many pandemics in history including measles, SARS, MERS, Ebola, and recently the novel Coronavirus disease caused by SARS-CoV-2. As of September 2021, it has affected over 200 million people and caused over 4 million deaths. India is the second most affected country in the world. Up to this date, more than 38 Lakh viral genomes have been submitted to public repositories like GISAID and NCBI to analyze the virus phylogeny and mutations. Here, we analyzed 2349 genome sequences of SARS-CoV-2 submitted in GISAID by a single institute pertaining to infections from the Gujarat state to know their variants and phylogenetic distributions with a major focus on the spike protein. More than 93% of the genomes had one or more mutations in the spike glycoprotein. The D614G variant in spike protein is reported to have a very high frequency of >95% globally followed by the L452R and P681R, thus getting significant attention. The antigenic propensity of a small peptide of 29 residues from 597 to 625 of the spike protein variants having D614 and G614 showed that G614 has a little higher antigenic propensity. Thus, the D614G is the cause for higher viral antigenicity, however, it has not been reported to be effective to be causing more deaths.

309 metagenome assembled microbial genomes from deep sediment samples in the Gulfs of Kathiawar Peninsula.

Prokaryoplankton genomes from the deep marine sediments are less explored compared to shallow shore sediments. The Gulfs of Kathiawar peninsula experience varied currents and inputs from different on-shore activities. Any perturbations would directly influence the microbiome and their normal homeostasis. Advancements in reconstructing genomes from metagenomes allows us to understand the role of individual unculturable microbes in ecological niches like the Gulf sediments. Here, we report 309 bacterial and archaeal genomes assembled from metagenomics data of deep sediments from sites in the Gulf of Khambhat and Gulf of Kutch as well as a sample from the Arabian Sea. Phylogenomics classified them into 5 archaeal and 18 bacterial phyla. The genomes will facilitate understanding of the physiology, adaptation and impact of on-shore anthropogenic activities on the deep sediment microbes.

Zinc oxide nanorod clusters deposited seaweed cellulose sheet for antimicrobial activity.

Seaweed cellulose was isolated from green seaweed Ulva fasciata using a common bleaching agent. Sheet containing porous mesh was prepared from the extracted seaweed crystalline cellulose along with zinc oxide (ZnO) nanorod clusters grown over the sheet by single step hydrothermal method. Seaweed cellulose and zinc oxide nanorod clusters deposited seaweed cellulose sheet was characterized by FT-IR, XRD, TGA, and SEM-EDX. Morphology showed that the diameter of zinc oxide nanorods were around 70nm. Zinc oxide nanorod clusters deposited on seaweed cellulose sheet gave remarkable antibacterial activity towards gram-positive (Staphylococcus aureus, Bacillus ceresus, Streptococcus thermophilis) and gram-negative (Escherichia coli, Pseudomonas aeruginous) microbes. Such deposited sheet has potential applications in pharmaceutical, biomedical, food packaging, water treatment and biotechnological industries.