An orphangyr B in the Mycobacterium smegmatis genome uncovered by comparative genomics

DNA gyrase is an essential topoisomerase found in all bacteria. It is encoded by gyrB and gyrA genes. These genes are organized differently in different bacteria. Direct comparison of Mycobacterium tuberculosis and Mycobacterium smegmatis genomes reveals presence of an additionalgyr B in M. smegmatis flanked by novel genes. Analysis of the amino acid sequence of GyrB from different organisms suggests that the orphan GyrB in M. smegmatis may have an important cellular role

Transcriptional specificity after mycobacteriophage I3 infection

Transcriptional regulation following mycobacteriophage I3 infection has been investigated. For this purpose, RNA polymerase mutants (rif) of host bacterium, Mycobacterium smegmatis have been isolated and characterised. Phage growth inrifs and rifr cells in presence of rifampicin revealed the involvement of host RNA polymerase in phage genome transcription. This was confirmed by studies onin vivo RNA synthesis as well as by direct RNA polymerase assay after phage infection. Significant stimulation in RNA polymerase activity was seen following phage infection. The maximal levels were attained in about 60 min post infection and maintained throughout the phage development period. The stimulation of polymerase activity was most pronounced when the phage DNA was used as the template. RNA polymerases from uninfected and phage-infected Mycobacterium smegmatis have been purified to homogeniety. The enzyme purification was accomplished by a rapid procedure utilising affinity chromatography on rifampicin-Sepharose columns. Subunit structure analysis of the purified RNA polymerase from uninfected and phage-infected cells showed the presence of α ,β , β ' and σ subunits similar to the other prokaryotic RNA polymerases. In addition, a polypeptide of 79, 000 daltons was associated with the enzyme after phage infection. The enzymes differed in their properties with respect to template specificity. Phage 13 DNA was the preferred template for the modified RNA polymerase isolated from infected cells which may account for the transcriptional switch required for phage development

Requirement for calcium ions in mycobacteriophage I3 DNA injection and propagation

Ca2+ ions are absolutely necessary for the propagation of mycobacteriophage I3 in synthetic medium. These ions are required for successful infection of the host and during the entire span of the intracellular development of the phage. A direct assay of the phage DNA injection using 32[p] labelled phage, shows that Ca2+ ions are necessary for the injection process. The injection itself is a slow process and takes 15 min to complete at 37°. The bacteria infected in presence of Ca2+ tend to abort if the ions are subsequently withdrawn from the growth medium. The effect of calcium withdrawal is maximally felt during the early part of the latent period; however, later supplementation of Ca2+ ions salvage phage production and the mature phage progeny appear after a delayed interval, proportional to the time of addition of Ca2+

Highly sensitive N-(1-naphthyl)ethylene diamine method for the spectrophotometric determination of trace amounts of nitrite in various water samples

A rapid, simple, sensitive and selective spectrophotometric determination of trace nitrite is described. The method is based on a diazotization-coupling reaction between dapsone and N-(1-naphthyl)ethylenediamine dihydrochloride (NEDA) in a hydrochloric acid medium. The molar absorptivity and Sandell's sensitivity were found to be 7.2x10(4) 1 mol(-1) cm(-1) and 0.00063 mug ml(-1), respectively. The calibration graph is linear for 0.002-0.6 mug ml(-1) of nitrite. The interference effects of various cations and anions were also studied and reported. This method has been found to be applicable to the determination of nitrite in various water samples

Study of price variation among the different brands of anti-tubercular drugs available in India

Background: India is one of the largest Tuberculosis (TB) burden countries in the world. Although Revised National Tuberculosis Control Programme provides free cost of therapy, sometimes patient get treated by private practioners. This can sometimes lead to irregular course of treatment due to decreased patient compliance. This in turn may lead to multi drug resistance among TB bacilli. One of the reasons for decreased patient compliance is cost of therapy. The present study was undertaken to evaluate the cost of therapy of various anti-TB drugs and their combinations available in India.Methods: The maximum and minimum cost in rupees (INR) of all anti-TB drugs manufactured by various pharmaceutical companies was noted. The cost of 10 tablets/capsules or their fixed dose combinations (FDCs) was calculated. The cost ratio and percentage price variation were calculated for each brand and compared.Results: Percentage variation in cost of oral anti-TB drugs marketed in India was highest in ethambutol 400mg (474.51), cycloserine 250mg (384.61), ethambutol 800mg (321.84) and rifampin 450mg (258.45). The lowest percentage cost variation was seen with pyrazinamide 225mg (10.04), ethambutol 1000mg (18.82) and rifampin 100mg (22.78). Among the FDCs lowest percentage cost variation seen with rifampin 150mg +isoniazid 75mg+pyrazinamide 400mg (0.16) and highest percentage cost variation is seen with rifampin 450mg+isoniazid 300mg+pyrazinamide 750mg+ethambutol 800mg (232.73).Conclusions: There is a significant variation in the cost of different brands of oral anti-TB drugs and their FDCs available in India. The National Pharmaceutical Pricing Authority (NPPA) should take more proactive steps for bringing down the prices of first line anti-TB drugs and the clinicians prescribing them should be aware of the price variation among the various brands of anti-TB drugs available in India

New spectrophotometric method for the determination of flutamide in pharmaceutical preparations

A sensitive and simple spectrophotometric method for the determinations of reduction product of flutamide (FLA) is described. The method is based on the interaction of diazotized flutamide reduction product with N-(1-naphthyl) ethylenediamine dihydrochloride (NEDA) in neutral or resorcinol (RSL) in alkaline medium. Absorbance of the resulting chromophores is measured at 525 or 480 nm, respectively, and is stable for at least 7 days. The two coupling reagents are applied successfully for the determination of FLA in tablets. The common excipients used as additives in pharmaceutical preparations do not interfere with the determination. Results from the analysis of pure FLA and its commercial tablets by the proposed methods agree well with the reported method. (C) 2000 Elsevier Science B.V. All rights reserved

Special Finsler spaces admitting metric like tensor field

In this work we modify the special Finsler spaces like C-reducible, semi-C-reducible, quasi-C-reducible are admitting the tensor field Xhk = hhk + X00lhlk, which satisfies the condition Cij hXhk = Cijk. Similarly, we have also worked out for S3-like, Ch-recurrent, P-reducible and T-conditions of Finsler spaces

Isolation, screening of Aspergillus flavus and its production parameters for á- amylase under solid state fermentation

The amylase producing fungi were isolated from spoiled fruits, vegetables and soil, in and around Bangalore, Karnataka, India. The isolates were identified and five fungal species were screened. The best amylase producer among them, Aspergillus sp was selected for enzyme production by both sub merged fermentation using mineral salt medium (MSM) and solid state fermentations using wheat bran as a solid substrate. The various parameters influencing solid state fermentation were optimized. The most important factors are such as pH, incubation temperature, incubation period, carbon sources, nitrogen sources and moisture content. The maximum amount of enzyme production was obtained when solid state fermentation was carried out with soluble starch as carbon source and beef extract (1% each) as nitrogen source, optimum conditions of pH 7.0, an incubation temperature of 25 (±2) °C, incubation time 96 h and 62% moisture content