University of Madras

About: University of Madras is a education organization based out in Chennai, Tamil Nadu, India. It is known for research contribution in the topics: Ring (chemistry) & Lipid peroxidation. The organization has 8496 authors who have published 11369 publications receiving 211152 citations. The organization is also known as: Madras University & University of Chennai.

Stereochemistry of nucleic acids and polynucleotides. IV. Conformational energy of base-sugar units

Abstract: In this paper, the preferred conformations of the bases with respect to the sugar in various base-sugar units are worked out using criteria of potential energy. The van der Waals type of intercations between nonbonded atoms is represented by a 6-12 function and the electrostatic interactions have been calculated in the monopole approximation using Coulomb's law. The torsional contributions to the total energy have been neglected. It is found that in general the pyrimidines have preferred anti contributions (as described by Donohue and Trueblood) and purines have both syn and anti and conformations. Certain differences between differently puckered riboses in regard to the above general tendency are discussed. The conclusions, in general, conform with the results obtained by us earlier with the use of hard-sphere potential and are also supported by observations on conformations of nucleotides and nucleotides in crystal structure.

Green synthesis of magnetic Fe3O4 nanoparticles using Couroupita guianensis Aubl. fruit extract for their antibacterial and cytotoxicity activities.

Abstract: In the present study, a sustainable green chemistry approach was established to fabricate magnetic Fe3O4 nanoparticles (Fe3O4NPs) using the aqueous fruit extract of edible C guianensis (CGFE) Synthesized NPs were further confirmed with different high-throughput characterization techniques such as UV–visible spectroscopy, FT-IR, XPS, DLS and zeta potential analysis Additionally, XRD, AFM, HRTEM and SQUID VSM demonstrate the generation of crystalline CGFe3O4NPs with mean diameter of 17 ± 10 nm Interestingly, CGFe3O4NPs exhibit a stupendous bactericidal action against different human pathogens which depicts its antimicrobial value A significant dose-dependent cytotoxic effect of CGFe3O4NPs was noticed against treated human hepatocellular carcinoma cells (HepG2)

Molecular Breeding for the Development of Blast and Bacterial Blight Resistance in Rice cv. IR50

Abstract: The objective of this study was to improve IR50, an elite Indica rice line, by molecular breeding approach involving marker-aided selection (MAS) and genetic transformation for resistance against blast (BL) and bacterial blight (BB). On the basis of BL pathogen population dynamics and lineage exclusion assays in southern India, the major BL resistance gene Piz-5 can exclude most Pyricularia grisea Sacc. {= P. oryzae Cavara [teleomorph: Magnaporthe grisea (Hebert) Barr]} lineages. Resistant C039 near-isogenic line (NIL) C101A51 carrying Piz-5 was used as the donor parent and IR50 as the recurrent parent in backcrossing up to four generations. BC4F1 plants were finally selfed to produce BC4F2 seeds. A polymerase chain reaction (PCR)-based sequence-tagged site (STS) marker RG64 was used to identify Piz-5 in the segregating population and the resultant resistant progenies were obtained through phenotypic assays and MAS. To have further resistance to bacterial blight in this cultivar, these blast-resistant isolines were transformed with Xa21, which is known to confer resistance to all races of Xanthomonas oryzae pv. Oryzae [= X. campestris pv. Oryza (Ishiyama 1922) Dye 1978] (Xoo). Stable integration and inheritance of the Xa21 gene were demonstrated by PCR and Southern blot analysis from three independent transformants. Bioassay data showed that transgenic IR50 is resistant to pathogens, M. grisea and Xoo. Apart from that, pedigree analysis and phenotypic studies with IR50 revealed the endogenous presence of the Xa4 gene, which may show an increased level of resistance to the BB pathogen along with the transformed Xa21 gene. This is the first report documenting the stacking of two major genes (Piz-5 + Xa21) in rice using molecular breeding through MAS and transformation.