Epigenetic Activation of Antibacterial Property of an Endophytic Streptomyces coelicolor Strain AZRA 37 and Identification of the Induced Protein Using MALDI TOF MS/MS

The endophytic Streptomyces coelicolor strain AZRA 37 was isolated from the surface sterilized root of Azadirachta indica A. Juss., commonly known as neem plant in India. Since only a few reports are available regarding epigenetic modulations of microbial entities, S. coelicolor was treated with different concentrations of 5-azacytidine for this purpose and evaluated for its antibacterial potential against five human pathogenic bacteria (Aeromonas hydrophila IMS/GN11, Enterococcus faecalis IMS/GN7, Salmonella typhi MTCC 3216, Shigella flexneri ATCC 12022 and Staphylococcus aureus ATCC 25923). The crude extract obtained from cultures treated with 25 μM concentration of 5-azacytidine, was found effective against all five pathogenic bacteria tested while the untreated control was only active against 3 pathogenic bacteria. HPLC analysis of crude compounds from treated cultures showed a greater number of compounds than that of the control. Extraction of whole cell protein and its SDS PAGE analysis showed an additional major protein band in 25 μM 5-azacytidine treated culture and MALDI TOF MS/MS analysis revealed that this protein belongs to the porin family.     

A novel promoter polymorphism (-71C>T) in KRTHB6 gene in Indian population

We have screened the basal promoter region, of KRTHB6 gene involving CAAT and TATA boxes in randomly selected 125 individuals of Indian origin by PCR-SSCP and DNA sequencing. We observed a novel promoter polymorphism (-71C>T) which could be differentiated by using LweI restriction enzyme. The frequency of -71 C allele, allele A (Accession no AY203963), was observed to be higher ( 0.712) in comparison to -71 T allele, allele B (0.288) (Accession no. AY037552).     

Mechanism of food detection in the tadpoles of the bronze frog <Emphasis Type="Italic">Rana temporalis</Emphasis>

Mechanism of food detection in Rana temporalis tadpoles was studied using a rectangular choice tank with end compartments (stimulus zones) providing exclusively visual and/or chemical food cues. Boiled spinach served as the food. The test tadpoles were starved for 24 h before use. They were released from the center of the choice tank (n=24) after 5 min of acclimation to test for end bias and food-detecting mechanism. The number of tadpoles in the two stimulus zones was recorded at 5-min intervals from 10 to 30 min. In the end-bias tests (without food cues) tadpole distribution was comparable at all times in the two compartments of the choice tank, exhibiting no end bias. In tests with the visual food cues provided in one of the stimulus zones, the tadpole distribution was also random. On the other hand, in experiments involving chemical cues emanating from food the tadpoles preferentially associated with the food source in significantly greater numbers compared to the zone lacking food or providing only a visual cue. The experiments with individual test tadpoles also revealed that they detect food based on chemical cues and ruled out copycat behavior. These findings on R. temporalis tadpoles reveal that chemical senses predominate over the visual senses in detection of food and foraging.     

Correlations between the benzene character of acenes or helicenes and simple molecular descriptors

Aromatic stabilities of acenes and helicenes, which are responsible for their biological, environmental and cancerous behavior have been modeled using a newly introduced Sadhana (Sd) and A indices. The results are compared with those obtained from PI (Padmakar-Ivan) index. The regression analysis has shown that excellent results are obtained by considering acenes and helicenes as separate classes of isomeric benzenoid hydrocarbons and that A index is better index than both PI and Sd indices.     

Tyrosine Phosphorylation on Spleen Tyrosine Kinase (Syk) Is Differentially Regulated in Human and Murine Platelets by Protein Kinase C Isoforms

Protein kinase C (PKC) isoforms differentially regulate platelet functional responses downstream of glycoprotein VI (GPVI) signaling, but the role of PKCs regulating upstream effectors such as Syk is not known. We investigated the role of PKC on Syk tyrosine phosphorylation using the pan-PKC inhibitor GF109203X (GFX). GPVI-mediated phosphorylation on Syk Tyr-323, Tyr-352, and Tyr-525/526 was rapidly dephosphorylated, but GFX treatment inhibited this dephosphorylation on Tyr-525/526 in human platelets but not in wild type murine platelets. GFX treatment did not affect tyrosine phosphorylation on FcRγ chain or Src family kinases. Phosphorylation of Lat Tyr-191 and PLCγ2 Tyr-759 was also increased upon treatment with GFX. We evaluated whether secreted ADP is required for such dephosphorylation. Exogenous addition of ADP to GFX-treated platelets did not affect tyrosine phosphorylation on Syk. FcγRIIA- or CLEC-2-mediated Syk tyrosine phosphorylation was also potentiated with GFX in human platelets. Because potentiation of Syk phosphorylation is not observed in murine platelets, PKC-deficient mice cannot be used to identify the PKC isoform regulating Syk phosphorylation. We therefore used selective inhibitors of PKC isoforms. Only PKCβ inhibition resulted in Syk hyperphosphorylation similar to that in platelets treated with GFX. This result indicates that PKCβ is the isoform responsible for Syk negative regulation in human platelets. In conclusion, we have elucidated a novel pathway of Syk regulation by PKCβ in human platelets.     

Prevalence of Pulmonary Tuberculosis among Adults in a North Indian District

BackgroundRecent population prevalence estimates of pulmonary tuberculosis (PTB) are not available for several areas in India. We conducted a field-based population survey at a north Indian district to estimate point prevalence of bacteriologically positive PTB.MethodsA stratified cluster sampling design was used to conduct the survey in both urban and rural areas within the district. All adults aged more than 15 years, in 18 rural and 12 urban clusters of 3000 subjects each, were interviewed using a symptom card. Two sputum samples were collected from all persons having symptoms suggestive of PTB, or history of antitubercular treatment, for smear microscopy for acid-fast bacilli and mycobacterial culture. Those having at least one sputum specimen positive on microscopy and/or culture were categorized as having PTB. Prevalence was estimated after adjusting for cluster sampling and incomplete data (through individual level analysis with robust standard error).ResultsOf 91,030 eligible adult participants (47,714 men and 43,316 women), 85,770 (94.2%) completed the symptom cards. Of them, 2,898 persons were considered eligible for sputum examination and 2,839 (98.0%) provided at least one sample. Overall, 21 persons had bacteriologically positive PTB, and cluster level prevalence was estimated at 24.5 per 100,000 population (95% CI 12.8–36.2). Individual level analysis with robust standard error yielded a prevalence estimate of 24.1 per 100,000 populations (95% CI 12.8–35.4).ConclusionThe observed prevalence of bacteriologically positive PTB in this district is lower than empiric national estimates, probably as a result of successful implementation of tuberculosis control measures in the area.