Life Sciences

<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

The stem-loop III (SLIII) structure within the 5′untranslated region has been shown to be critical for internal initiation of translation of Hepatitis C virus (HCV). Using 'Single Strand Conformation Polymorphism (SSCP)' of the SLIII region we have investigated for natural mutations and demonstrated presence of some non-covariant changes in certain sub-domains. However, overall SLIII-RNA structure was found to be phylogenetically conserved. Additionally, by SSCP analysis we have determined the genotype of 50 HCV isolates collected from Southern India, 25 random samples were confirmed by DNA sequencing. Results showed the prevalence of genotype 1 in this part of India. © Springer-Verlag 2004.

World University root node

(SoNS) School of Natural Sciences

Archives of Virology

Phylogenetic conservation of the stem-loop III structure of the 5′untranslated region of Hepatitis C virus RNA among natural variants in samples collected from Southern India

Bacterial Blight (BB) caused by Xanthomonas oryzae pv. oryzae is a major disease of rice in tropical Asia. Since all the Basmati varieties are highly susceptible and the disease is prevalent in the entire Basmati growing region of India, BB is a severe constraint in Basmati rice production. The present study was undertaken with the objective of combining the important Basmati quality traits with resistance to BB by a combination of phenotypic and molecular marker-assisted selection (MAS). Screening of 13 near-isogenic lines of rice against four isolates of the pathogen from Basmati growing regions identified the Xa4, xa8, xa13 and Xa21 effective against all the isolates tested. Two or more of these genes in combination imparted enhanced resistance as expressed by reduced average lesion length in comparison to individual genes. The two-gene pyramid line IRBB55 carrying xa13 and Xa21 was found equally effective as three/four gene pyramid lines. The two BB resistance genes present in IRBB55 were combined with the Basmati quality traits of Pusa Basmati-1 (PB-1), the most popular high yielding Basmati rice variety used as recurrent parent. Phenotypic selection for disease resistance, agronomic and Basmati quality characteristics and marker-assisted selection for the two resistance genes were carried out in BC 1F 1, BC 1F 2 and BC 1F 3 generations. Background analysis using 252 polymorphic amplified fragment length polymorphism (AFLP) markers detected 80.4 to 86.7% recurrent parent alleles in BC 1F 3 selections. Recombinants having enhanced resistance to BB, Basmati quality and desirable agronomic traits were identified, which can either be directly developed into commercial varieties or used as immediate donors of BB resistance in Basmati breeding programs.

Molecular Breeding

Combining bacterial blight resistance and Basmati quality characteristics by phenotypic and molecular marker-assisted selection in rice

Several 6-aryloxymethyl-2,4-dimethyl-1,2,4-triazolo [3,4-b]-1,3,4- thiadiazepines II and 2-arylamino-4-aryloxymethyl-1,2,4-triazolo [3,4-b][1,3,4] thiadiazoles III have been synthesized from the synthon 3-aryloxymethyl-4-amino- 5-mercapto-1,2,4-triazoles I. The molluscicidal activity of few titled compounds have been evaluated against the snail Lymnaea acuminata. The LC50 slope, t-ratio, heterogeneity and g values have been determined and discussed.

Indian Journal of Heterocyclic Chemistry

Synthesis and molluscicidal activity of 6-aryloxymethyl-2,4-dimethyl-1,2,4- triazolo [3,4-b]-[1,3,4]-thiadiazepines and 2-arylamino-4-aryloxymethyl-1,2,4- triazolo [3,4-b] [1,3,4] thiadiazoles

Microsatellite markers were used for fingerprinting of hybrids, assessing variation within parental lines and testing the genetic purity of hybrid seed lot in rice. Ten sequence tagged microsatellite sites (STMS) markers were employed for fingerprinting 11 rice hybrids and their parental lines. Nine STMS markers were found polymorphic across the hybrids and produced unique fingerprint for the 11 hybrids. A set of four markers (RM 206, RM 216, RM 258 and RM 263) differentiated all the hybrids from each other, which can be used as referral markers for unambiguous identification and protection of these hybrids. Cluster analysis based on Jaccard's similarity coefficient using UP-GMA grouped the hybrids into three clusters. Within the cluster all the hybrids shared a common cytoplasmic male sterile line as female parent. The genetic similarity between the hybrids ranged from 0.33 to 0.92 with an average similarity index of 0.63. The analysis of plant-to-plant variation within the parental lines of the hybrid Pusa RH 10, using informative markers indicated residual heterozygosity at two marker loci. This highlights the importance of STMS markers in maintaining the genetic purity of the parental lines. The unique value of the restorer gene linked marker for testing the genetic purity of hybrid seeds is demonstrated for the first time.

Euphytica

Molecular fingerprinting of hybrids and assessment of genetic purity of hybrid seeds in rice using microsatellite markers

The low-molecular-weight (LMW) penicillin-binding protein, PBP 5, plays a dominant role in determining the uniform cell shape of Escherichia coli. However, the physiological functions of six other LMW PBPs are unknown, even though the existence and enzymatic activities of four of these were established three decades ago. By applying fluorescence-activated cell sorting (FACS) to quantify the cellular dimensions of multiple PBP mutants, we found that the endopeptidases PBP 4 and PBP 7 also influence cell shape in concert with PBP 5. This is the first reported biological function for these two proteins. In addition, the combined loss of three DD-carboxypeptidases, PBPs 5 and 6 and DacD, also impaired cell shape. In contrast to previous reports based on visual inspection alone, FACS analysis revealed aberrant morphology in a mutant lacking only PBP 5, a phenotype not shared by any other strain lacking a single LMW PBP. PBP 5 removes the terminal D-alanine from pentapeptide side chains of muropeptide subunits, and pentapeptides act as donors for cross-linking adjacent side chains. As endopeptidases, PBPs 4 and 7 cleave cross-links in the cell wall. Therefore, overall cell shape may be determined by the existence or location of a specific type of peptide cross-link, with PBP 5 activity influencing how many cross-links are made and PBPs 4 and 7 acting as editing enzymes to remove inappropriate cross-links.

Fulltext

Journal of Bacteriology

Endopeptidase penicillin-binding proteins 4 and 7 play auxiliary roles in determining uniform morphology of Escherichia coli

Several (2-substituted)-spiro(cyclohexane)-1′ ,5-[1,3,4]oxadiazolo[3,2-c]thiazolines 3 and (2-substituted)-spiro(cyclohexane)-1′,5-[1,3,4]thiadiazolo[3,2-c] thiazolines 6 have been synthesised from 3-arylamido-spiro(cyclohexane)-1′ ,2-(4-thiazolidinone) 2 and 3-(N-substituted arylthiocarbanilido)-spiro(cyclohexane)-1′,2-(4-thiazolidinone) 5 respectively which in turn have been prepared by reaction of 1-aroylcyclohexane-hydrazone 1 and 1-aryl-4-cyclohexane thiosemicarbazone 4 with thioglycollic acid respectively. The molluscicidal activity of few title compounds has been evaluated against snail Lymnaea acuminata.

Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry

Synthesis and molluscicidal activity of (2-substituted)-spiro(cyclohexane)-1′,5-[1,3,4]oxa/thiadiazolo[3,2-c] thiazolines

We report here the expression and purification of a truncated form of the hepatitis E virus ORF2 protein (ORF2Δ111/ΔTM), from the fat bodies of Spodoptera litura larvae infected with a recombinant baculovirus. The purified protein migrated as a doublet of ∼56 kDa on SDS-PAGE and was found to be glycosylated by staining with concanavalin A-linked horseradish peroxidase. The protein was used in a sensitive and specific enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to HEV. The results showed complete concordance with those obtained using a commercial kit for the detection of anti-HEV antibodies. Antigen expression in the insect larvae system presents a rapid and low-cost method that obviates the need for expensive tissue culture scale-ups or special equipment. © 2002 Elsevier Science (USA). All rights reserved.

Protein Expression and Purification

Purification and diagnostic utility of a recombinant hepatitis E virus capsid protein expressed in insect larvae

Current Science

Female sex-associated RAPD marker in pointed gourd (Trichosanthes dioica Roxb.)

Bombyx mori nucleopolyhedrosis virus (BmNPV), a natural pathogen of great economic significance in sericulture, has been exploited to generate recombinant baculoviruses harbouring genes of choice and achieve high level expression of cloned foreign genes. The BmNPV-based expression system offers the advantage of using the larval host rather than the insect-derived cell lines for economic large-scale synthesis of biomolecules. Since commercial rearing of silkworms is routinely practised, a part of the silkworm stocks can be diverted to produce biomolecules other than silk and the more sophisticated tissue culture methodologies can be dispensed with on an industrial scale. Nonetheless, the BmNPV-based expression considerably lags behind the AcMNPV system in vogue today, in terms of the choice of expression-optimized cloning vectors and easy recombinant generation kits that are commercially available. This review provides a brief outline of the current state of knowledge on the basic biology and genomics of BmNPV and how the virus has been made use of to produce biomolecules through its larval host, the mulberry silkworm. Since hyper-transcription from the viral very late gene promoters forms the basis of high level expression through recombinant baculoviruses, some aspects of the viral gene transcription and the role of late gene expression factors have also been included in the review.

Bombyx mori nucleopolyhedrovirus: Molecular biology and biotechnological applications for large-scale synthesis of recombinant proteins

The hepatitis E virus (HEV) is the causative agent of hepatitis E, an acute form of viral hepatitis. The biology and pathogenesis of HEV remain poorly understood. We have used in vitro binding assays to show that the HEV ORF3 protein (pORF3) binds to a number of cellular signal transduction pathway proteins. This includes the protein tyrosine kinases Src, Hck, and Fyn, the p85α regulatory subunit of phosphatidylinositol 3-kinase, phospholipase Cγ, and the adaptor protein Grb2. A yeast two-hybrid assay was used to further confirm the pORF3-Grb2 interaction. The binding involves a proline-rich region in pORF3 and the src homology 3 (SH3) domains in the cellular proteins. Competition assays and computer-assisted modeling was used to evaluate the binding surfaces and interaction energies of the pORF3-SH3 complex. In pORF3-expressing cells, pp60src was found to associate with an 80-kDa protein, but no activation of the Src kinase was observed in these cells. However, there was increased activity and nuclear localization of ERK in the pORF3-expressing cells. These studies suggest that pORF3 is a viral regulatory protein involved in the modulation of cell signaling. The ORF3 protein of HEV appears to be the first example of a SH3 domain-binding protein encoded by a virus that causes an acute and primarily self-limited infection.