Synthesis and Structural Characterization of Selenium Nanoparticles-Bacillus sp. MKUST-01 Exopolysaccharide (SeNPs-EPS) Conjugate for Biomedical Applications.

Exopolysaccharides (EPS) are exogenous microbial metabolites generated predominantly during the development of bacteria. They have several biological potentials, including antibacterial, antioxidant, and anticancer actions. Polysaccharide-coated nanoparticles have high biological activity and are used in treatments and diagnostics. In this research, selenium nanoparticles (SeNPs) are synthesized and conjugated with bacterial (Bacillus sp. MKUST-01) exopolysaccharide (EPS). Initially, the creation of SeNPs conjugates was verified through UV-Vis spectral examination, which exhibited a prominent peak at 264 nm. Additionally, X-ray diffraction (XRD) analysis further substantiated the existence of crystalline Se, as evidenced by a robust reflection at 29.78°. Another reflection observed at 23.76° indicated the presence of carbon originating from the EPS. Fourier transform infrared spectroscopy (FT-IR) analysis of the EPS capped with SeNPs displayed characteristic peaks at 3425 cm-1, 2926 cm-1, 1639 cm-1, and 1411 cm-1, corresponding to the presence of O-H, C-H, C=O, and COO-groups. The SeNPs themselves were found to possess elongated rod-shaped structures with lengths ranging from 250 to 550 nm and a diameter of less than 70 nm, as confirmed using scanning electron microscopy and particle size analysis. In contrast to the SeNPs, the SeNPs-EPS conjugates showed no hemolytic activity. The overall antioxidant activity of SeNPs-EPS conjugates outperformed 20% higher than SeNPs and EPS. Additionally, experimental observations involving gnotobiotic Artemia nauplii experiments were also recorded, such as the supplementation of EPS and SeNPs-EPS conjugates corresponding to enhanced growth and increased survival rates compared to Artemia nauplii fed with SeNPs and a microalgal diet.

Drug Resistance, Characterization and Phylogenetic Discrepancy of Salmonella enterica Isolates from Distinct Sources.

Salmonella enterica is one of the foodborne pathogens that can infect humans, spreading from one person to another by contaminated food and water. To identify the pathogenic S. enterica from the contaminated food product, culture-based and molecular identifications, drug resistance profiling, virulence and genetic traits of the strains have been used. Herein, different animal products was subjected to screen for S. enterica prevalence, pathogenic characterization and compared with clinical Salmonella isolates (human). A total of 173 isolates from animal products and 51 isolates from clinical samples were collected. S. Typhi, S. Agona and S. Ohio were predominant serovars in blood, stool and different animal products. Both, clinical [37% (n = 19/51)] and animal product-associated isolates [21% (n = 37/173)] expressed their highest resistance to nalidixic acid. Thirty-one percentage of (n = 16/51) clinical isolates and 12% (n = 21/173) animal food-associated isolates were resistant to multiple classes of antibiotics. Class 1 integrons encoded by S. Typhi, S. Infantis and S. Emek were screened for sequence analysis, the result revealed that the cassettes encoded-aminoglycoside acetyltransferase and dihydrofolate reductase enzymes. Salmonella pathogenicity island-1 encoded-hilA gene was detected most frequently in all the isolates. PFGE profile revealed the genetic traits of the isolates which were closely linked with antibiotic-resistant properties and virulent characteristics. Only S. Enteritidis, collected from different samples had clonal similarities. In summary, drug-resistant pathogenic Salmonella prevalence was observed in the animal product that could be an important alarm to consumers with the risk of enteric fever and it causes the potential risk to public health.

Identification of coral endosymbionts of Veedhalai and Mandapam coasts of Palk Bay, India using small subunit rDNA.

Coral endosymbionts act as a bio-indicator of coral ecosystem under extreme environmental conditions. The health of the coral ecosystem depends on the endosymbiont cell density of the coral hosts. Therefore, it is of interest to analyze ten coral fragments found to be under the genera Acropora, Favites, Favia, and Porites collected at various locations from Veedhalai to Mandapam, southeast coast of India during January 2019 to March 2019. The zooxanthellae cell count ranged between 4.08 (Porites sp.9) and 13.75x105 cells cm2 -1 (Favites sp.3). This indicates the health of the corals in the region. The genus (clade) level identification of endosymbionts was detected using the host excluding primers of small subunit DNA (nssrDNA). Bidirectional sequencing of 18S nrDNA gene (SSU) of all ten coral fragments show that the Veedhalai corals is associated with the genus Durusdinium (Clade D) but the corals of Mandapam is associated with the genera, Cladocopium (Clade C) and Durusdinium (Clade D). It is known that the thermal stress has negative impact on coral reef ecosystem of the world. The dominance of the genus Durusdinium in the scleractinian corals of Palk Bay may be due to frequent exposure to thermal stress. This thermotolerant endosymbionts is opportunistic. Thus, the corals of Veedhalai and Mandapam coasts, Palk Bay, India are necessarily packed with thermotolerant endosymbionts enabling conservation.

Using different cultivation strategies and methods for the production of microalgal biomass as a raw material for the generation of bioproducts.

Microalgal biomass and its fine chemical production from microalgae have pioneered algal bioprocess technology with few limitations such as lab-to-industry. However, laboratory-scale transitions and industrial applications are hindered by a plethora of limitations comprising expensive in culturing methods. Therefore, to emphasize the profitable benefits, the algal culturing techniques appropriately employed for large-scale microalgal biomass yield necessitates intricate assessment to emphasize the profitable benefits. The present review holistically compiles the culturing strategies for improving microalgal biomass production based on appropriate factors like designing better bioreactor designs. On the other hand, synthetic biology approaches for abridging the effective industrial transition success explored recently. Prospects in synthetic biology for enhanced microalgal biomass production based on cultivation strategies and various mechanistic modes approach to enrich cost-effective and viable output are discussed. The State-of-the-art culturing techniques encompassing enhancement of photosynthetic activity, designing bioreactor design, and potential augmenting protocols for biomass yield employing indoor cultivation in both (Open and or/closed) methods are enumerated. Further, limitations hindering the microalgal bioproducts development are critically evaluated for improving culturing techniques for microalgal cell factories, subsequently escalating the cost-benefit ratio in bioproducts synthesis from microalgae. The comprehensive analysis could provide a rational and deeper detailed insight for microalgal entrepreneurs through alternative culturing technology viz., synthetic biology and genome engineering in an Industrial perspective arena.

Molecular insights of Carbapenem resistance Klebsiella pneumoniae isolates with focus on multidrug resistance from clinical samples.

BACKGROUND: Carbapenem are the last-line antibiotic, defence against Gram-negative extended spectrum ß-lactamases producers (ESBLs). Carbapenem resistance Enterobacteriaceae especially Carbapenem resistant-Klebsiella pneumoniae (CR-KP) is recognized as one of the well-known public health problem, which is increasingly being reported around the world. The present study was focused to analyse the prevalence and characterization of antibiotic resistance K. pneumoniae in centre region of Tamil Nadu, India. METHODOLOGY: Totally 145 suspected K. pneumoniae isolates [Urine, Pus, Sputum, Blood and Biopsy] obtained from hospitals of Central South India. The isolates were subjected to biochemical and molecular identification technique, following with antibiotic resistance pattern by standard antibiotic sensitivity test. Multidrug resistance (MDR) with ß-lactamase producing Carbapenem resistant K. pneumoniae (CR-KP) strains were screened by classical sensitivity method and also drug resistance encoded gene. Also, molecular typing of the MDR strains were characterized by Pulsed-Field Gel Electrophoresis (PFGE). Further, the outer membrane protein (OmpK35 and 36) related Carbapenem resistance were characterized. RESULTS: Totally, 61% of isolates were confirmed as K. pneumoniae, 75 % of isolates were MDR including 58% carbapenem and 97% ESBL antibiotics and grouped into 17 distinct resistant patterns. The MDR KP isolates shows positive for blaCTXM-1 (92 %) gene followed by blaSHV (43 %), blaTEM (36 %), blaNDM-1 (26 %), blaGES (20 %) and blaIMP-1 (8 %). Moreover, 62 % CR-KP isolates loses OmpK36 and 33% isolates loses OmpK35. CONCLUSIONS: Loss of OmpK36 were highly an influence the cefoxitin and carbapenem resistance. Sixteen different PFGE patterns have been observed among the 18 MDR isolates. Eventually, ESBL as well as CR-KP were diverse in genetic makeup and often associated with hyper virulence hvKP should be of serious concern.

Draft Genome Sequence of Carotenoid Producing Yellow Pigmented Planococcus maritimus MKU009.

Planococcus maritimus MKU009 is a Gram positive cocci and a moderate halophilic bacterium isolated from marine water of Pichavaram, South East Coast of India. Here we report the draft genome of Planococcus maritimus MKU009 with a total size of 3,251,644 bp with N50 value of 1681571 bp. The overall G+C content of the genome was 47.27%. The carotenoid producing crtN, crtB, crtP and crtI genes were located within the first contig of the genome assembly. This genome source will provide insights into functional genomics of carotenoid production and metabolic engineering.