A nano-biosensor for DNA sequence detection using absorption spectra of SWNT-DNA composite

biosensor based on Single Walled Carbon Nanotube (SWNT)-Poly (GT)n ssDNA hybrid has been developed for medical diagnostics. The absorption spectrum of this assay is determined with the help of a Shimadzu UV-VIS-NIR spectrophotometer. Two distinct bands each containing three peaks corresponding to first and second van Hove singularities in the density of states of the nanotubes were observed in the absorption spectrum. When a single-stranded DNA (ssDNA) having a sequence complementary to probic DNA is added to the ssDNA-SWNT conjugates, hybridization takes place, which causes the red shift of absorption spectrum of nanotubes. On the other hand, when the DNA is noncomplementary, no shift in the absorption spectrum occurs since hybridization between the DNA and probe does not take place. The red shifting of the spectrum is considered to be due to change in the dielectric environment around nanotubes. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2212

Hospital Wastewater Sludge: An Unaddressed Environmental Reservoir for Emerging and Rare Nosocomial Pathogens

Nosocomial infections cause significant mortality and financial losses each year. Most of these infections are caused by multidrug resistant (MDR) opportunistic pathogens and therefore are difficult to treat by standard therapies. Though hospitals are considered as ecological niches for nosocomial pathogens, environmental reservoirs for the same are still underexplored. The present study addressed this issue by systematically profiling the pathogenic diversity of hospital wastewater sludge hypothesized as an important reservoir for nosocomial pathogens within a hospital setting using Illumina Miseq Next Generation Sequencing (NGS) approach. The NGS data showed that i) nosocomial pathogens dominated the hospital sludge bacterial profile and majority of them fell in the category of either emerging or rare pathogens ii) Majority of the pathogens formed part of the low abundant microbiota represented by 3.56% of the reads iii) Nearly 14% of the reads were represented by the unculturable bacteria iv) Of the 580 species-level operational taxonomic units (OTUs) identified in this study, 166 matched with potential human pathogens v) Enterobacter cloacae (56.45%) was the most dominant species followed by  Pseudomonas putida (6.07%), Fusobacterium ulcerans (3.08%) Acidaminococcus fermentans (2.03%) respectively. Aeromonas hydrophila, Klebsiella pneumoniae and Pantoea agglomerans formed the less dominant species. This study points towards the catastrophic effect on public health and environment that may result from the co-treatment of hospital wastewater with domestic wastewater in municipal wastewater treatment plants and the use of resultant sludge in agriculture which is a common method of sludge disposal practiced in developing countries. Keywords: Hospital sludge, Next Generation Sequencing, Nosocomial Pathogens, Emerging Pathogens, Rare Pathogens &nbsp

A master switch to tackle drought stress

In SATrends issues 62 (Jan 2006) and 75 (Feb 2007), we reported that when the DREB1A gene driven by the promoter of a stress-inducible gene, rd29A, was genetically introduced into groundnuts, it not only improved the transpiration efficiency, but also induced a positive root respons

The Magneto Rotatory Behaviour of some Optically Active Substances in Solution

It deals with the Magneto Rotatory Behaviour of some Optically Active Substances in Solution@IAC

Genetic transformation of pigeonpea: An overview

Biotechnology over the years has emerged as a promising tool to overcome biotic and abiotic constraints in crop species that lack the required traits for crop improvement through conventional and molecular breeding approaches. New engineering tools are now available not only for single gene traits, but also to engineer multiple genes or plant regulatory machinery for driving the expression of different stress responsive genes. Here, we discuss the recent progress and current status of transgenic technology in pigeonpea towards developing host plant resistance to various biotic and abiotic stresses and its use in the improvement of this important pulse crop

Peanut (Arachis hypogaea L.)

Arachis hypogea (peanut, groundnut), an annual oil seed belonging to the Leguminosae family and the Papillionacea subfamily, is a legume native to South America but now grown in diverse environments in six continents between latitudes 40°N and 40°S. Arachis hypogea can grow in a wide range of climatic conditions. The low yields of this crop are mainly attributed to unreliable rainfall patterns with frequent droughts, lack of highyielding adapted cultivars, damage by diseases and pests, poor agronomic practices, and limited use of inputs. Genetic engineering approaches have been shown to be comparatively fast, leading to better isolation and cloning of desired traits for combating the various biotic and abiotic stresses. This chapter describes an Agrobacterium-mediated transformation protocol in peanut using the cotyledon system. The system described here is potentially applicable to a vast range of genotypes with a high transformation frequency of >70% based on the preliminary molecular data, indicating the production of a large number of independently transformed transgenic plants. The method reported here provides opportunities for crop improvement of this important legume crop via genetic transformation

Tackling toxins

Aflatoxins are toxic and carcinogenic substances produced by fungi such as Aspergillus flavus and A. parasiticus on a variety of food products. Contamination of groundnut (peanut) with mycotoxins such as aflatoxin has assumed significance in semi-arid regions of the world where over 4.5 billion people are exposed to uncontrolled amounts of these toxins. Although aflatoxin contamination does not affect crop productivity, it makes the produce unfit for consumption. Aflatoxin B1, the most toxic, is a potent carcinogen associated with liver cance