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A new ligand N,N'-bis{3-(2-formyl-4-methyl-phenol)-6-iminopropyl}oxamide (L) and its mono- and binuclear copper(II) complexes have been synthesized and characterized. The ligand shows absorption maxima at 249 and 360 with a weak transition at 455 nm. The ligand was found to be fluorescent and shows an emission maximum at 516 nm on excitation at 360 nm. The electronic spectra of the mono- and binuclear Cu(II) complexes exhibited a d-d transition in the region 520-560 nm characteristic of square planar geometry around Cu(II) ion. The ESR spectrum of the mononuclear complex showed four lines with nuclear hyperfine splitting. The binuclear complex showed a broad ESR spectrum with g=2.10 due to antiferromagnetic interaction between the two Cu(II) ions. The room-temperature magnetic moment values (micro(eff)) for the mono- and binuclear Cu(II) complexes are found to be 1.70 micro(B) and 1.45 micro(B), respectively. The electrochemical studies of the mononuclear Cu(II) complex showed a single irreversible one-electron wave at -0.70 V (E(pc)) and the binuclear Cu(II) complex showed two irreversible one-electron reduction waves at -0.75 V (E(pc)(1)) and -1.27 V (E(pc)(2)) in the cathodic region.

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AIM: To study the effect of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase from Pseudomonas fluorescens against saline stress under in vitro and field conditions in groundnut (Arachis hypogea) plants. METHODS AND RESULTS: Four plant growth-promoting rhizobacteria (PGPR) strains were used in this study to evaluate their efficacy in groundnut plants against saline stress under in vitro. Among the four PGPR strains used, Ps. fluorescens strain TDK1 showed greater performance in improving the plant growth parameters of groundnut seedlings in vitro. PCR amplification using Pseudomonas-specific 16S-23S rRNA internal transcribed spacers (ITS) primers revealed that all the four strains belonged to the group of fluorescent pseudomonads. ITS region of Ps. fluorescens strain TDK1 was cloned and sequenced. ACC deaminase activity using biochemical and molecular (PCR) analysis revealed that among all the four strains, Ps. fluorescens strain TDK1 showed greater amount of ACC deaminase activity and positive reaction to PCR amplification. ACC deaminase gene from Ps. fluorescens strain TDK1 was isolated, cloned and sequenced. Pseudomonas bioformulations were developed and they were tested in groundnut plants under saline-affected soils. The results indicated the superior performance by Ps. fluorescens strain TDK1 possessing ACC deaminase activity in improving yield parameters in groundnut plants despite salinity. CONCLUSIONS: Pseudomonas fluorescens strain TDK1 possessing ACC deaminase activity enhanced the saline resistance in groundnut plants, which in turn resulted in increased yield when compared with the groundnuts treated with Pseudomonas strains not having ACC deaminase activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The promising role of ACC deaminase from Ps. fluorescens strain TDK1 in alleviating saline stress has been concluded in groundnut plants. This study will be useful for exploiting the activity of ACC deaminase from microbial strains against various biotic and abiotic stresses wherever ACC accumulated as precursor for ethylene biosynthesis.

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We have developed a simple, economical and reproducible method for processing blood samples from HIV infected patients for diagnosis of tuberculosis. The procedure was validated on 55 samples selected for tuberculosis based on clinical criteria. 52 patients had radiological changes indicative of pulmonary tuberculosis of which only 28 were positive for AFB in sputum (sensitivity 54%) and 27 for tuberculin (sensitivity 52%). 26 HIV positive patients who showed positive X-ray did not react to tuberculin. The genus PCR probe missed 3 samples (sensitivity 94%) compared to X-ray.M.tuberculosis was detected in the blood of all X-ray positive cases by PCR using TB400 probe (sensitivity 100%) and another probe forM. tuberculosis, IS6110, missed 6 of them (sensitivity 88% compared to X-ray and 89% compared to TB400). It is proposed that this simple sample processing method could be used to screen all blood samples quickly for mycobacteremia using the genus PCR and only those positive for mycobacteria need to be tested forM.tuberculosis. This would save the scarce resources and time by reducing significantly the number of samples to be screened for species confirmation.

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We have isolated and identified the biotype of environmental mycobacteria from the expectorate of leprosy patients, their contacts, their drinking water supply and also from the sputa samples of tuberculosis patients. 78% of the isolates from lepromatous leprosy patients and their contacts wereMycobacterium fortuitum- chelonae complex (MFC), 9%Mycobacterium avium complex (MAC), 9%Mycobacterium scrofulaceum and 4% wereMycobacterium smegmatis. Among the isolates from tuberculosis patients 63% belonged toM. fortuitum- chelonae complex, 19% toM. avium complex, 12% toMycobacterium Kansasii and 6% toM. smegmatis. All the isolates were multi-drug resistant when tested for sensitivity total of 21 drugs. TheMycobacterium fortuitum-chelonae complex organisms from leprosy contacts were more sensitive to rifampicin than those isolated from lepromatous leprosy and tuberculosis patients. Among 23 isolates from leprosy patients one isolate was resistant to 20 drugs, one isolate to 17 drugs and another isolate was resistant to 13 drugs. Among the 18 isolates from drinking water supply six showed resistance to more than 12 drugs. Polymerase Chain Reaction (PCR) and subsequent hybridisation with specific probes confirmed all the isolated strains as nontuberculous mycobacteria (Using genus primers and probe sensitivity 100%) and none asM. tuberculosis, suggesting that PCR could be used to rapidly identify mycobacteria at the genus level and to rule out tuberculosis in leprosy patients at an early stage to decide on appropriate course of therapy.