Rhythmic oscillations in KaiC1 phosphorylation and ATP/ADP ratio in nitrogen-fixing cyanobacterium Cyanothece sp. ATCC 51142

Cyanobacterial circadian clock composed of the Kai oscillator has been unraveled in the model strain Synechococcus elongatus PCC 7942. Recent studies with nitrogen-fixing Cyanothece sp. ATCC 51142 show rhythmic oscillations in the cellular program even in continuous light albeit with a cycle time of ~11 h. In the present study, we investigate correlation between cellular rhythms, KaiC1 phosphorylation cycle, ATP/ADP ratio, and the redox state of plastoquinone pool in Cyanothece. KaiC1 phosphorylation cycle of Cyanothece was similar to that of Synechococcus under diurnal cycles. However, under continuous light, the cycle time was shorter (11 h), in agreement with physiological and gene expression studies. Interestingly, the ATP/ADP ratio also oscillates with an 11 h period, peaking concomitantly with the respiratory burst. We propose a mathematical model with C/N ratio as a probable signal regulating the clock in continuous light and emphasize the existence of a single timing mechanism regardless of the cycle time.     

Design and optimization of fermentation medium for enhanced bacteriocin production by probiotic bacterium Enterococcus faecium MC13

Statistics-based experimental designs were used to develop a cost-effective medium for enhanced production of viable cells and bacteriocin by probiotic Enterococcus faecium MC13. Carbon, nitrogen, and mineral sources were first screened by one-variable-at-a-time (OVAT) methods. In order to increase yield production, the selected variables were further statistically optimized using response-surface methodology (RSM) with central composite design (CCD). The maximum and minimum levels of the selected variables were determined and a set of 34 experimental runs was performed. The optimum concentrations of the tested variables for production of viable cells (12.24 log CFU mL(-1)) and bacteriocin activity (25,600 AU mL(-1)) were tryptone (10.0 g/L), peptone (6.0 g/L), maltose (3.0 g/L), glucose (9.0 g/L), NaCl (15.0 g/L), sodium citrate (2.5 g/L), sodium acetate (1.0 g/L), and dipotassium PO(4) (0.1 g/L). Threefold increased yield of bacteriocin was achieved in optimized medium compared to the unoptimized counterpart, and this was two times less cost than commercial MRS medium.     

Isolation, Characterization and Identification of a Potential Probiont from South Indian Fermented Foods (Kallappam, Koozh and Mor Kuzhambu) and Its Use as Biopreservative

Twenty-five strains of lactic acid bacteria (LAB) isolated from South Indian traditional fermented foods Kallappam batter, Koozh and Mor Kuzhambu. Further 6 strains were selected based on their antimicrobial activity. They were identified according to morphological, biochemical and physiological criteria. Identification by 16S rDNA sequence homology of the isolates revealed the presence of Weissella paramesenteroides, Lactobacillus plantarum and Lactobacillus fermentum. Lactobacillus plantarum AS1 showed maximum antimicrobial activity among 6 strains and this strain was chosen for biopreservation. When male Albino Wistar rats were fed with L. plantarum AS1 (approx. 10⁹ cells/mL for a month), there was no sign of any illness and they were on par with control rats in terms of weight gain/week. In the L. plantarum AS1–treated group, there was reduction in the populations of indigenous microflora of coliforms, yeast and molds; however, the lactobacilli population increased comparatively. L. plantarum AS1 was able to retain its normal growth in the presence of increasing concentration of bile salt in the MRS and it also tolerated the artificial gastric juice simulating the condition inside the stomach where it was viable for 24 h with bacterial count of 6.079 logCFU/mL. L. plantarum AS1 reduced the cholesterol in the MRS broth by 57.3%. Hence, all these properties established it as an effective probiont. L. plantarum AS1 found to be an effective biopreservative in cheese, where it decreased the population of Salmonella typhi by 2.95 log cycles.     

Development of eSSR-Markers in Setaria italica and Their Applicability in Studying Genetic Diversity,Cross-Transferability and Comparative Mapping in Millet and Non-Millet Species

Foxtail millet ( Setaria italica L.) is a tractable experimental model crop for studying functional genomics of millets and bioenergy grasses. But the limited availability of genomic resources, particularly expressed sequence-based genic markers is significantly impeding its genetic improvement. Considering this, we attempted to develop EST-derived-SSR (eSSR) markers and utilize them in germplasm characterization, cross-genera transferability and in silico comparative mapping. From 66,027 foxtail millet EST sequences 24,828 non-redundant ESTs were deduced, representing ~16 Mb, which revealed 534 (~2%) eSSRs in 495 SSR containing ESTs at a frequency of 1/30 kb. A total of 447 pp were successfully designed, of which 327 were mapped physically onto nine chromosomes. About 106 selected primer pairs representing the foxtail millet genome showed high-level of cross-genera amplification at an average of ~88% in eight millets and four non-millet species. Broad range of genetic diversity (0.02–0.65) obtained in constructed phylogenetic tree using 40 eSSR markers demonstrated its utility in germplasm characterizations and phylogenetics. Comparative mapping of physically mapped eSSR markers showed considerable proportion of sequence-based orthology and syntenic relationship between foxtail millet chromosomes and sorghum (~68%), maize (~61%) and rice (~42%) chromosomes. Synteny analysis of eSSRs of foxtail millet, rice, maize and sorghum suggested the nested chromosome fusion frequently observed in grass genomes. Thus, for the first time we had generated large-scale eSSR markers in foxtail millet and demonstrated their utility in germplasm characterization, transferability, phylogenetics and comparative mapping studies in millets and bioenergy grass species.     

Production and purification of a novel exopolysaccharide from lactic acid bacterium Streptococcus phocae PI80 and its functional characteristics activity in vitro

Optimum culture conditions which ease the synthesis of a novel exopolysaccharide (EPS) from a potent marine strain Streptococcus phocae was proposed in this study. The strain grows well at 35 °C, pH 7.0 and NaCl (2%) with lactose and yeast extract as best carbon and nitrogen sources. The maximum yield of EPS (11.75 and 12.14 g/L) was obtained in the presence of lactose and yeast extract at a concentration of 20 g/L respectively. EPS was refined by gel filtration chromatography using phenyl Sepharose column which revealed the presence of arabinose, fructose and galactose sugar units with molecular mass about 2.8 × 10⁵ Da. Emulsifying and flocculating stability of EPS compared with three commercial hydrocolloids. EPS exhibited better activities which are similar to that of commercial hydrocolloids. Both crude and purified EPS exhibited strong antioxidant potential by quenching hydroxyl and superoxide anion radicals. Antibiofilm activity by inhibition of Gram positive and Gram negative biofilm forming bacteria was evident in our studies. Potential antioxidant activity and biofilm inhibiting property of EPS may lead to the development of novel food grade adjuncts.     

Oxidation of CaMKII determines the cardiotoxic effects of aldosterone

Excessive activation of the β-adrenergic, angiotensin II (Ang II) and aldosterone signaling pathways promotes mortality after myocardial infarction, and antagonists targeting these pathways are core therapies for treating this condition. Catecholamines and Ang II activate the multifunctional Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), the inhibition of which prevents isoproterenol-mediated and Ang II-mediated cardiomyopathy. Here we show that aldosterone exerts direct toxic actions on myocardium by oxidative activation of CaMKII, causing cardiac rupture and increased mortality in mice after myocardial infarction. Aldosterone induces CaMKII oxidation by recruiting NADPH oxidase, and this oxidized and activated CaMKII promotes matrix metalloproteinase 9 (MMP9) expression in cardiomyocytes. Myocardial CaMKII inhibition, overexpression of methionine sulfoxide reductase A (an enzyme that reduces oxidized CaMKII) or NADPH oxidase deficiency prevented aldosterone-enhanced cardiac rupture after myocardial infarction. These findings show that oxidized myocardial CaMKII mediates the cardiotoxic effects of aldosterone on the cardiac matrix and establish CaMKII as a nodal signal for the neurohumoral pathways associated with poor outcomes after myocardial infarction.     

Cryopreservation and microencapsulation of a probiotic in alginate-chitosan capsules improves survival in simulated gastrointestinal conditions

The aim of the present study was to focus on the impact of two different methods and the effects of cryoprotectants on the survival of a probiotic bacterium, Streptococcus phocae PI80, during storage. For the protection of freeze dried cells, the optimal storage conditions were determined with a high survival rate. After the freeze drying process, all cryoprotectants exhibited a protective effect on cell viability at all storage temperatures. High relative cell viability was observed when cells were incubated at ?20°C, which was optimum for the protection of S. phocae PI80. Trehalose was the most promising cryoprotectant at all temperatures during the storage period of bacterial cells. The combination of trehalose + skim milk showed more than 85% survivability compared to other combinations at ?20°C for 60 days. In addition, encapsulation of probiotic cells into alginate-chitosan gel capsules showed better survival of S. phocae cells (5.468 ± 0.15 LogCFU/mL) with high bacteriocin activity at ?20°C for six months. The cell-loaded microcapsules remained stable when treated with simulated gastric and intestinal fluids. After 6 h in vivo treatment, the capsules were found to be broken, releasing the probiotic cells directly into the intestinal system of rats. Therefore, microencapsulation was found to be the most efficient technique, which not only protected the cells for a longer time but also released the cells into the in vivo intestinal system.     

Fine needle aspiration cytology of primary lymphoid lesions of the orbit: report of four cases

BACKGROUND: The role offine needle aspiration cytology (FNAC) in diagnosis and differentiation of primary orbital lymphoid lesions is debatable, and little literature exists on cytodiagnosis of orbital lymphoid lesions. CASES: Four patients with orbital lesions underwent routine FNAC. In 3 cases, histopathologic examination was performed with immunohistochemistry (IHC). Cytologic features and diag- noses were correlated with histopathologic diagnoses. Two were cytologically diagnosed with low-grade non-Hodgkin lymphoma (NHL) and 2 with pseudolymphoma and inflammatory pseudotumor, respectively. Of the 2 cases of histologically diagnosed NHL, 1 had concordant diagnosis and the other had a jalse negative diagnosis of pseudolymphoma; both showed significant increase in mast cells, with neoplastie lymphoid cells exhibiting a higher N:C ratio and coarser chromatin texture. The case cytologically interpreted as suspicious for NHL was identified as a psetedolymphoma on histology (false positive). The case of inflammatory pseudotumor, in which hiopiy was not peiformned, responded well to corticosteroids, strengthening the cytologic diagnosis. CONCLUSION: FNAC diagnosis and differentiation of benign vs. malignant primacy orbital lymphoid lesions is often difficult. Careful cytologic interpretation with respect to certain subtle cytologic details is needed in minimizing false positive or false negative diagnoses. In difficult situations, IHC using suitable immunomarkers proves highly useful.