Amphomycin: A tool to study protein N-glycosylation

Radio-labelled amphomycin (³H-amphomycin) forms a complex with dolichylmonophosphate in presence of Ca²⁺. Complex formation has also been documented with retinylmonophosphate and perhydromonoeneretinylmonophosphate. Analysis of the space-filling model suggested both fatty acylated aspartic acid residue at the N-terminus of the lipopeptide and phosphate head group of dolichylmonophosphate are necessary for the complex formation. The binding ability of amphomycin is then utilized to localize dolichylmonophosphate in the microsomal membrane. Studies with microsomal membranes from hen oviduct suggested that dolichylmonophosphate is located in the cytoplasmic side of the membrane.     

Fatty acid synthesis in fetal lung

De novo fatty acid synthesis in lung is significant during fetal growth and development. Specific activity and relative rate of synthesis of fatty acid synthetase increase with the days of gestational age and drop significantly after birth. Fetal lungs contain thyroid hormone receptors and binding capacities of this hormone to the fetal lungs also increase with the days of gestational age. Our results suggest that de novo fatty acid synthesis in fetal lungs may make a significant contribution towards surfactant synthesis.     

Molecular epidemiology of plasmid patterns in Shigella dysenteriae type I obtained from an outbreak in West Bengal (India)

Abstract Multiple antibiotic-resistant Shigella dysenteriae type 1 isolates from a recent epidemic in West Bengal (India) showed identical plasmid patterns. All isolates were resistant to ampicillin (Am), chloramphenicol (Cm), tetracycline (Tc), streptomycin (Sm) and trimethoprim (Tp) and contained 6 plasmids, ranging from 2.5–120 kb. The Am resistance determinant was located on the 120 kb plasmid. This plasmid was unstable when the S. dysenteriae strains were grown above 37°C. The Bangladesh strains of S. dysenteriae type 1 showed identical plasmid patterns, except that many isolates were Am-sensitive and lacked the 120 kb plasmid. In strains from both Bangladesh and West Bengal, predominantly group-B plasmids conferred resistance to Cm and Tc. Comparisons of Eco R1 fragments generated from the total plasmid DNA content of each strain support the view that the plasmids present in the S. dysenteriae type 1 strains isolated from all recent epidemics in India and Bangladesh were identical.     

Acyl-CoA: sn-Glycerol-3-Phosphate O-Acyltransferase in Rat Brain Mitochondria and Microsomes

Abstract: The subcellular distribution of acyl-CoA: sn -glycerol-3-phosphate O-acyltransferase between brain mitochondria and microsomes was investigated. The activities associated with purified rat brain mitochondrial and microsomal preparations could be distinguished by differences in their acyl-CoA specificity, products of acylation, and sensitivity to N -ethylmaleimide, trypsin, acetone, and polymyxin B. It was concluded that both brain mitochondria and microsomes possess the acyltransferase.     

Exploration of highly selective fluorogenic ‘on–off' chemosensor for H2PO4− ions: ICT‐based sensing and ATPase activity profiling

Abstract In this study, the recognition contour of Chemosensor 1 was investigated using semiaqueous methanol (X_H, mole fraction = 0.31) for a range of anions and bioactive species. Host–receptor signalling based on the internal charge transfer mechanism for Chemosensor 1 was explored and reported. Structure of Chemosensor 1 and its plausible anion coordination based on hydrogen bonding is complemented with density functional theory. Consequently, we investigated the applicability of the synthesized probe in blood plasma, urine, tap water samples, and for monitoring of ATP in lysosomes by apyrase enzyme.     

Increased accumulation of phenolic metabolites in groundnut (Arachis hypogaea L.) genotypes contribute to defense against Sclerotium rolfsii infection

Abstract

Fungal infections cause several metabolic changes to the plants, which can affect its physiology and survival in various ways. In the present study, we have analysed various phenolic compounds and activity of oxidative enzymes in healthy and Sclerotium rolfsii-infected groundnut genotypes. Increased phenolics content and higher activity of oxidative enzymes was observed in the tolerant genotype (CS 19, GG 16) followed by susceptible genotype (GG 20, TG 37A). Among the phenolic compounds tested, chlorogenic acid content has increased greatly in leaf, stem and root of infected tolerant genotypes compared to the respective controls. In vitro growth of S. rolfsii showed significant inhibition at concentrations 500 and 1000 µg/mL of phenolic compounds in the radial growth inhibition assay. These results have strongly suggested that, higher accumulation of chlorogenic acid could be an important factor in imparting resistance and protecting groundnut against S. rolfsii infection in tolerant genotypes.     

A Unique Combination of Nutritionally Active Ingredients Can Prevent Several Key Processes Associated with Atherosclerosis In Vitro

Introduction

Atherosclerosis is the underlying cause of cardiovascular disease that leads to more global mortalities each year than any other ailment. Consumption of active food ingredients such as phytosterols, omega-3 polyunsaturated fatty acids and flavanols are known to impart beneficial effects on cardiovascular disease although the combined actions of such agents in atherosclerosis is poorly understood. The aim of this study was to screen a nutritional supplement containing each of these active components for its anti-atherosclerotic effect on macrophages in vitro.

Results

The supplement attenuated the expression of intercellular adhesion molecule-1 and macrophage chemoattractant protein-1 in human and murine macrophages at physiologically relevant doses. The migratory capacity of human monocytes was also hindered, possibly mediated by eicosapentaenoic acid and catechin, while the ability of foam cells to efflux cholesterol was improved. The polarisation of murine macrophages towards a pro-inflammatory phenotype was also attenuated by the supplement.

Conclusion

The formulation was able to hinder multiple key steps of atherosclerosis development in vitro by inhibiting monocyte recruitment, foam cell formation and macrophage polarisation towards an inflammatory phenotype. This is the first time a combination these ingredients has been shown to elicit such effects and supports its further study in preclinical in vivo models.     

Alteration in the in vitro activity of milk leukocytes during different parity in high yielding cross-bred cows

In vitro activity of milk leukocytes (viz. neutrophils, lymphocytes and macrophages) was evaluated in forty-eight (48) clinically healthy high-yielding cross-bred cows of mid-lactation stage (100–200 days of lactation), divided into four groups namely 1st parity (n = 12), 2nd parity (n = 12), 3rd parity (n = 12) and 4th and above parity (n = 12). Milk samples were taken (250 ml/cow) were taken. Milk somatic cell counts (SCC) and differential leukocyte counts (DLC) were performed microscopically. In vitro phagocytic index (PI) of milk neutrophils and macrophages was evaluated by colorimetric nitro blue tetrazolium reductive assay. Mitogen-induced milk lymphocyte blastogenic response was measured by colorimetric MTT (tetrazolium) assay after isolation of the milk leukocytes by density gradient centrifugation. Milk SCC differed significantly (p < 0.01) between different parity. Cows of 4 and above parity showed significantly (p < 0.01) higher milk SCC compared to primiparous cows. There was no significant difference in milk DLC during different parities in high-yielding cross-bred cows. There was a significant (p < 0.01) variation in lymphocyte blastogenesis amongst parity. The highest value of lymphocyte blastogenesis was seen at 3rd parity, whereas lowest value was obtained in the cows of both 1st and 4th or above parity. PI of milk neutrophils did not differ significantly between parity. PI of milk macrophages was significantly (p < 0.01) higher in 3rd parity and lower (p < 0.01) in 1st and 4th parities. The study indicated that depressed activity of milk lymphocytes and macropages was lower and SCC was higher in the cows of 4th and above parity indicating more mammary stress and hence susceptible to udder infection and mastitis. Therefore, better care and managemental interventions should be taken around these periods.