Effect of Copper on Morphology, Weight, and Chromosomal Aberrations in the Spiny Lobster, Panulirus homarus (Linnaeus, 1758)

Spiny lobster Panulirus homarus which had been exposed to cupric ion at 9.55 and 19.1?μg/l for 28?days was examined for sub-lethal effects including morphology, wet weight, and induced genotoxic effect on the chromosome. Following cupric exposure, the color of lobster P. homarus changed from yellowish-brown to greenish black in the hepatopancreas, changed from normal creamy white to yellowish white in the muscle, and changed to greenish black in the gill. A significant change in the percentage of wet weight of muscle (28.70?±?0.41-23.47?±?0.45), hepatopancreas (4.03?±?0.12-2.63?±?0.17), and gills (3.63?±?0.45-3.87?±?0.12) were observed in the copper-treated lobsters. The diploid number of chromosomes of P. homarus was over 200 metaphases from ten lobsters, as 2n?=?58, and consisted of 16 acrocentric, seven metacentric, and six sub-metacentric chromosomes. The lobsters exposed to cupric ion at 9.55 and 19.1?μg/l showed different types of chromosomal aberrations such as centromeric gaps, chromatid breaks, centromeric fusion, stickiness, ring chromosomes, and acrocentric association region. The frequency of aberrations increased with duration of exposure. In conclusion, it was suggested that cupric ion interacts with the spindle formation and consequently distorts the normal karyomorphology, indicating cytogenetic effect on lobster.     

Bioinspired Gold Nanoparticle Synthesis Using Terminalia bellerica Fruit Parts and Exploring Their Anti‐bacterial Potency In Vitro

Gold nanoparticles with their excellent biocompatibility are extensively used in pharma and biological applications. Terminalia bellerica (TB) dry fruit parts mediated gold nanoparticles were synthesized using the aqueous extracts. The secondary metabolites screening of the aqueous extracts was done using phytochemical analysis. The green synthesized gold nanoparticles show vibrant colours. They were characterized using UV–Visible spectroscopy, FT-IR spectroscopy, XRD analysis and FE-SEM. The analytical characterization methods ensured the formation of nanoparticles and could predict the nanometric size of the nanoparticles. The study also lay to determine the antibacterial potential of the TB fruit parts and TB fruit parts mediated gold nanoparticles. The pathogens chosen for the study were pathogens from clinical species such as Acinetobacter pneumonia, Bacillus subtilis, and Enterococcus faecalis which cause common infections. The TB fruit part extracts, as well as TB fruit parts mediated gold nanoparticles were capable enough to destroy clinical pathogens.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12088-021-00937-3.     

Probing the structure of Leishmania major DHFR TS and structure based virtual screening of peptide library for the identification of anti-leishmanial leads

Leishmaniasis, a multi-faceted ethereal disease is considered to be one of the World's major communicable diseases that demands exhaustive research and control measures. The substantial data on these protozoan parasites has not been utilized completely to develop potential therapeutic strategies against Leishmaniasis. Dihydrofolate reductase thymidylate synthase (DHFR-TS) plays a major role in the infective state of the parasite and hence the DHFR-TS based drugs remains of much interest to researchers working on Leishmaniasis. Although, crystal structures of DHFR-TS from different species including Plasmodium falciparum and Trypanosoma cruzi are available, the experimentally determined structure of the Leishmania major DHFR-TS has not yet been reported in the Protein Data Bank. A high quality three dimensional structure of L.major DHFR-TS has been modeled through the homology modeling approach. Carefully refined and the energy minimized structure of the modeled protein was validated using a number of structure validation programs to confirm its structure quality. The modeled protein structure was used in the process of structure based virtual screening to figure out a potential lead structure against DHFR TS. The lead molecule identified has a binding affinity of 0.51?nM and clearly follows drug like properties.     

Antibacterial activities of Groebke–Blackburn–Bienaymé-derived imidazo[1,2-a]pyridin-3-amines

We sought to explore the imidazo[1,2-a]pyridin-3-amines for TLR7 (or 8)-modulatory activities. This chemotype, readily accessed via the Groebke–Blackburn–Bienaymé multi-component reaction, resulted in compounds that were TLR7/8-inactive, but exhibited bacteriostatic activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). To investigate the mechanism of antibacterial activity of this new chemotype, a resistant strain of S. aureus was generated by serially passaging the organism in escalating doses of the most active analogue. A comparison of minimum inhibitory concentrations (MICs) of known bacteriostatic agents in wild-type and resistant strains indicates a novel mechanism of action. Structure–activity relationship studies have led to the identification of positions on the scaffold for additional structural modifications that should allow for the introduction of probes designed to examine cognate binding partners and molecular targets, while not significantly compromising antibacterial potency.     

Caffeine in tea plants [Camellia sinensis (L) O. Kuntze]: in situ lowering by Bacillus licheniformis (Weigmann) Chester

Tea plants (Camellia sinensis) contain 5-6% caffeine that is responsible for the stimulating effect of the beverage. As the tolerance to caffeine varies among individuals, low caffeine tea would be an ideal alternative. While assessing the potential of a few selected bacteria-Bacillus licheniformis, B. subtilis and B. firmus, to multiply on nutrient medium supplemented with glucose (5%) and tea leaf extract (2%), it was observed that only B. licheniformis could proliferate on this medium. Hence, B. licheniformis was used for further studies. Tea plants were sprayed with a suspension of B. licheniformis at a dilution of 5 x 10(8) CFU/ml containing 0.1% Tween 80 as surfactant. In situ lowering of caffeine from tea leaves was evident without affecting the quality of the other tea components. Further, there was no change in the morphological and physiological characteristics as well. It is suggested that spraying of B. licheniformis may be useful in yielding decaffeinated tea with good flavour and aroma.     

Effects of different supplements to low protein and poor quality protein diets on performance and brain enzymes in the albino rat

Groups of albino rats were fed low and high protein diets and the former group was fed with different supplements. The supplements used were niacin, pyridoxine and glutamic acid. A low protein diet was found to decrease the activities of l -glutamate-NAD-oxidoreductase and l -glutamate-1-carboxy-lyase in the cerebrum; this confirmed the results of previous work in this laboratory. Addition of glutamic acid to a low protein diet was found to reverse the effects of a low protein diet to some extent. Groups of animals were fed kodri (Paspalum scorbiculatum), a millet deficient in lysine, with or without lysine itself or foodstuffs rich in it, e.g. moth bean (Phaseolus aconitifolius Jacq.), peas (Pisum sativuni) and skim milk powder. When combined, the groups fed on the lysine or lysine-source supplemented diets were found to perform better in a water maze on the basis of the relative ease with which they could reverse a previous learned pattern. They also had higher activities of l -glutamate-NAD-oxidoreductase and l -glutamate-1-carboxy-lyase than groups with no lysine or lysine source added. There was no significant difference between the groups receiving the different lysine supplements.