Muhammad Manjurul Karim

Lates calcarifer (Asian seabass) is a euryhaline perciform fish of significant aquaculture and fisheries importance across the Indo-West Pacific, including Bangladesh. Despite its economic value, no complete mitochondrial genome from Bangladeshi populations has been characterized, limiting understanding of its evolutionary relationships and intraspecific genetic diversity. The complete mitochondrial genome of L. calcarifer was sequenced using Illumina next-generation sequencing, assembled with GetOrganelle v1.7.7, and annotated using MITOS2. The mitogenome is 16,623 bp in length, encoding 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and an 880 bp non-coding control region (D-loop), arranged in canonical vertebrate gene order. Overall AT content was 54.26% with positive AT-skew (+0.0624) and negative GC-skew (−0.3130), consistent with typical teleost strand asymmetry. Among 3,798 sense codons, CGA (Arg) was the most over-represented (RSCU = 2.421). All 13 PCGs evolved under purifying selection (Ka/Ks = 0.0176–0.1331). The control region contained conserved TAS and CSB motifs, and the origin of light-strand replication was identified within the WANCY cluster. Maximum-likelihood analysis placed the Bangladesh sequence (PZ501434) within the Indian Ocean/Bay of Bengal (IND) lineage as a strongly supported sister to Malaysian OP359071.1 (BS = 100%; 99.74% identity), while showing only 92.14% identity to the Southeast Asian reference (NC_007439.1; Singapore), supporting the existence of at least two well-differentiated mitochondrial lineages within L. calcarifer across the Indo-West Pacific. This study presents the first complete mitochondrial genome of L. calcarifer from Bangladesh, providing a genomic reference for evolutionary analysis, population genomics, and sustainable aquaculture management of Asian seabass in the Bay of Bengal.

Priestia aryabhattai MS3, a plant growth-promoting (PGP) bacterium isolated from saline rice fields of Bangladesh, was subjected to whole-genome sequencing

Seasonal flooding in Bangladesh poses severe public health risks through waterborne disease, yet a comprehensive, genomic‐level understanding of the associated microbial hazards is lacking. This study presents a comprehensive shotgun metagenomic analysis of floodwaters from four districts of Bangladesh (Cumilla, Feni, Lakshmipur, and Noakhali) during the devastating 2024 floods, profiling the distribution of pathogenic bacteria, antimicrobial resistance genes, and virulence factors. A total of 12 samples were collected during peak flooding periods and processed using Illumina sequencing. Taxonomic profiling and resistome analysis were performed using MetaPhlAn4, ABRicate, and MEGAHIT, referencing the NCBI and CZ ID databases. Across all regions, 301 operational taxonomic units were identified. Feni exhibited the highest diversity of pathogenic species, including multidrug‐resistant Klebsiella pneumoniae , toxigenic Pseudomonas aeruginosa , and mobilizable resistance plasmids (e.g., IncP1, Col440I). Noakhali samples revealed co‐detection of zoonotic and emerging pathogens such as Aliarcobacter spp. and Streptococcus suis , along with key resistance genes like blaOXA and ermB . Microbial community clustering revealed strong spatial heterogeneity. This study provides genomic evidence that floodwaters harbour emerging pathogens and AMR. It strongly advocates for incorporating metagenomic tools into Bangladesh's national flood response and AMR monitoring frameworks.

Flooding events alter microbial communities, impacting soil health and ecosystem recovery. This study examined the 2024 Bangladesh floods' effects on microbial diversity in agricultural and residential soils. We collected paired soil samples from six flooded and two non‐flooded sites within a single rural subdistrict after the floods. This sample size was logistically feasible for an initial survey and provides a foundational data set for future larger‐scale investigations. Our findings revealed that flooding increased microbial diversity and facilitated the dispersal of unique taxa, with 45 species shared between flooded groups compared to only 6 in non‐flooded controls. Notably, 29 beneficial microbes introduced post‐flood were identified, categorized into 8 functional groups critical for soil recovery. Residential soils were enriched in nitrogen‐fixing microbes, whereas agricultural soils showed higher abundance of phosphate solubilizers and plant growth‐promoting rhizobacteria. Sulfur/iron cyclers and cyanobacteria demonstrated flood‐adaptive roles. Pathogen screening identified no canonical human pathogens with the exception of Clostridium disporicum , detected only in one non‐flooded sample. Archaea from Woesearchaeales and bacteria from the Gemmataceae dominated the microbial communities. Flooded environments harbored unique taxa, such as Sulfuricurvum sp. and the Nitrospira genus, which were absent in controls. Alpha diversity analysis revealed a higher Chao1 richness in flooded soils compared to controls, although statistical significance was not found due to insufficient sample size. Beta diversity showed greater variability between flooded soils relative to non‐flooded controls, also not statistically significant. These findings demonstrate that flooding can act as a driver for dispersing beneficial microbes, supporting soil restoration and enhancing agricultural resilience.

Phytate, an antinutritional molecule in poultry feed, can be degraded by applying phytase, but its use in low- and middle-income countries is often limited due to importation instead of local production. Here, inexpensive raw materials were used to optimize the production of a thermostable phytase from an indigenous strain of Bacillus subtilis SP11 that was isolated from a broiler farm in Dhaka. SP11 was identified using 16s rDNA and the fermentation of phytase was optimized using a Plackett–Burman design and response surface methodology, revealing that three substrates, including the raw material mustard meal (2.21% w/v), caused a maximum phytase production of 436 U/L at 37 °C and 120 rpm for 72 h, resulting in a 3.7-fold increase compared to unoptimized media. The crude enzyme showed thermostability up to 80 °C (may withstand the feed pelleting process) with an optimum pH of 6 (near pH of poultry small-intestine), while retaining 96% activity at 41 °C (the body temperature of the chicken). In vitro dephytinization demonstrated its applicability, releasing 978 µg of inorganic phosphate per g of wheat bran per hour. This phytase has the potential to reduce the burden of phytase importation in Bangladesh by making local production and application possible, contributing to sustainable poultry nutrition.

Salinity and heavy metal stress significantly reduce agricultural productivity in arable lands, particularly affecting crops like rice (Oryza sativa L.). This study aimed to evaluate the efficacy of heavy metal-tolerant plant growth-promoting rhizobacteria (HMT-PGPR) in mitigating the harmful effects of salt (NaCl), chromium (Cr), and combined NaCl + Cr stress on rice plants. Two pre-isolated and well-characterized heavy metal-tolerant epiphytic (Ochrobactrum pseudogrignonense strain P14) and endophytic (Arthrobacter woluwensis strain M1R2) PGPR were tested. The LSD test (p ≤ 0.05) was used to assess the statistical significance between treatment means. Stresses caused by NaCl, Cr, and their combination were found to impair plant growth and biomass accumulation through mechanisms, including osmotic stress, oxidative damage, ionic imbalance, reduced photosynthetic pigment, lowered relative water content, and compromised antioxidant defense systems. Conversely, inoculation with HMT-PGPR alleviated these adverse effects by reducing oxidative stress indicators, including malondialdehyde (MDA), hydrogen peroxide (H₂O₂) content and electrolyte leakage (EL) and enhancing plant growth, osmolyte synthesis, and enzymatic antioxidant activity under single- and dual-stress conditions. The application of HMT-PGPR notably restricted Na⁺ and Cr⁶⁺ uptake, with an endophytic A. woluwensis M1R2 demonstrating superior performance in reducing Cr⁶⁺ translocation (38%) and bioaccumulation (42%) in rice under dual stress. The findings suggest that A. woluwensis effectively mitigates combined salinity and chromium stress by maintaining ion homeostasis and improving the plant’s antioxidant defenses.

Priestia aryabhattai strain MS3, a salt-tolerant, plant growth-promoting rhizobacterium, was isolated from saline soil in Kalapara, Patuakhali, Bangladesh. This study presents the whole-genome sequencing of strain MS3, revealing a 5.296 Mb genome comprising 5,369 predicted protein-coding sequences and 46 RNA genes.

We report the complete mitochondrial genome sequence of the giant tiger prawn ( Penaeus monodon ) from Bangladesh. The circular genome spans 15,979 base pairs, with a GC content of 29.04%, and encodes 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and 1 control region.