Rakesh Tuli

Publications (86)217.53 Total impact

• Source

  Available from: Dinesh K Yadav

  Dataset: Localization of Rabies Virus Glycoprotein into the Endoplasmic

  Dinesh Yadav, Krishan Mohan Rai, Meenal Srivastava, Praveen C Verma, Pradhyumna K Singh, Rakesh Tuli
• Article: A new betasatellite associated with cotton leaf curl Burewala virus infecting tomato in India: influence on symptoms and viral accumulation.

  Jitendra Kumar, Samatha Gunapati, Sudhir P Singh, Abhinav Kumar, Adarsh Lalit, Naresh C Sharma, Rekha Puranik, Rakesh Tuli
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  ABSTRACT: A begomovirus and its associated alpha- and betasatellite were detected in tomato plants affected with leaf curl disease. Based on a nucleotide sequence identity of 99 %, this begomovirus was designated an isolate of cotton leaf curl Burewala virus (CLCuBuV). The alphasatellite exhibited 93 % sequence identity to cotton leaf curl Burewala alphasatellite (CLCuBuA) and is hence referred to here as a variant of CLCuBuA. The detected betasatellite was recombinant in nature and showed 70 % sequence identity to the known betasatellites. Inoculation of healthy tomato with CLCuBuV plus betasatellite, either in the presence or the absence of alphasatellite, led to typical leaf curling, while inoculation with CLCuBuV in the absence of betasatellite resulted in mild symptoms. This confirmed the role of the betasatellite in expression of disease symptoms. We propose to name the newly detected betasatellite tomato leaf curl Hajipur betasatellite (ToLCHJB).
  Archives of Virology 01/2013; · 2.11 Impact Factor
• Article: Detection and characterization of a new betasatellite: variation in disease symptoms of tomato leaf curl Pakistan virus-India due to associated betasatellite.

  Jitendra Kumar, Sudhir P Singh, Abhinav Kumar, Jawaid A Khan, Rakesh Tuli
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  ABSTRACT: A begomovirus and its associated betasatellites were amplified and sequenced from tobacco plants affected with leaf curl disease. The begomovirus was identified as a new strain of tomato leaf curl Pakistan virus (ToLCPKV), which is referred to here as ToLCPKV-India. A previously known betasatellite [tomato leaf curl Patna betasatellite (ToLCPaB)] and a new betasatellite were also found in leaf-curl-affected samples. The use of infectious clones of ToLCPKV-IN plus ToLCPaB for agroinoculation led to typical leaf curl, while ToLCPKV-IN together with the new betasatellite resulted in curling and chlorosis of leaves. Based on these disease symptoms, we propose to name the new betasatellite tobacco leaf chlorosis betasatellite (TbLChB).
  Archives of Virology 09/2012; · 2.11 Impact Factor
• Article: A novel mastrevirus infecting wheat in India.

  Jitendra Kumar, Sudhir P Singh, Jitesh Kumar, Rakesh Tuli
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  ABSTRACT: A new mastrevirus (family Geminivridae) infecting wheat in India was detected by rolling-circle amplification (RCA). The complete nucleotide sequence of the virus was determined to be 2783 bp long. Analysis of the nucleotide sequence revealed identity and a genome organisation typical of a mastrevirus. An identical virus was detected in the candidate insect vector (leafhopper) collected from the field. Agroinoculation of young wheat plants with an infectious clone of the virus resulted in dwarfing of plants, identical to what was observed in the field, confirming that this novel virus was the causative agent of the disease. Considering the low degree of sequence identity to any known mastrevirus, the virus described here is suggested to be a member of a new species. Based on symptoms, we propose the name "wheat dwarf India virus".
  Archives of Virology 07/2012; 157(10):2031-4. · 2.11 Impact Factor
• Article: Sterol glycosyltransferases-identification of members of gene family and their role in stress in Withania somnifera.

  Pankaj Chaturvedi, Manoj Mishra, Nehal Akhtar, Parul Gupta, Pratibha Mishra, Rakesh Tuli
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  ABSTRACT: Sterol glycosyltransferases (SGTs) catalyze the transfer of sugar molecules to diverse sterol molecules, leading to a change in their participation in cellular metabolism. Withania somnifera is a medicinal plant rich in sterols, sterol glycosides and steroidal lactones. Sterols and their modified counterparts are medicinally important and play a role in adaptation of the plant to stress conditions. We have identified 3 members of SGT gene family through RACE (Rapid Amplification of cDNA Ends) in addition to sgtl1 reported earlier. The amino acid sequence deduced from the ORF's showed homology (45-67 %) to the reported plant SGTs. The expression of the genes was differentially modulated in different organs in W. somnifera and in response to external stimuli. Salicylic acid and methyl jasmonate treatments showed up to 10 fold increase in the expression of sgt genes suggesting their role in defense. The level of expression increased in heat and cold stress indicating the role of sterol modifications in abiotic stress. One of the members, was expressed in E. coli and the enzyme assay showed that the crude enzyme glycosylated stigmasterol. W. somnifera expresses a family of sgt genes and there is a functional recruitment of these genes under stress conditions. The genes which are involved in sterol modification are important in view of medicinal value and understanding stress.
  Molecular Biology Reports 06/2012; 39(10):9755-64. · 2.93 Impact Factor
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  Available from: Dinesh K Yadav

  Article: Localization of rabies virus glycoprotein into the endoplasmic reticulum produces immunoprotective antigen.

  Dinesh K Yadav, Shadma Ashraf, Pradhyumna K Singh, Rakesh Tuli
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  ABSTRACT: Rabies virus surface glycoprotein (rabies G-protein) with (G+RS) and without (G-RS) endoplasmic reticulum retrieval signal was expressed and characterized in tobacco plants. Transgenically expressed rabies G-protein was estimated at 0.015-0.38 % of total leaf protein. The relative migration of the rabies G-protein on SDS-PAGE was at the position, as anticipated for the viral coat protein (~66 kDa). Immunolocalization by confocal microscopy established that immunoprotective G+RS expressed in tobacco was primarily confined to ER. G+RS showed binding to Con A lectin and was susceptible to N-glycosidase F activity similar to native rabies G-protein. However, the G-RS transgenically expressed in tobacco leaves was glycosylated differently and was resitant to N-glycosidase F. Immunological studies and Rapid Fluorescent Foci Inhibition Test (RFFIT) showed that G+RS was immunogenic and immunoprotective, whereas G-RS was moderately immunogenic but non-protective against live virus challenge. Hence, plants can express the antigenic component of rabies virus with suitable glycosylation, which is important to give protection against rabies virus infection.
  The Protein Journal 05/2012; 31(6):447-56. · 1.04 Impact Factor
• Article: EST-derived SSR markers in Jatropha curcas L.: development, characterization, polymorphism, and transferability across the species/genera

  Hemant Kumar Yadav, Alok Ranjan, Mehar Hasan Asif, Shrikant Mantri, Samir V. Sawant, Rakesh Tuli
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  ABSTRACT: A total of 12,080 sequences, including 5,851 transcriptome contigs developed at NBRI and 5,002 singlets and 1,227 contigs assembled from 13,201 expressed sequence tags (ESTs) of Jatropha curcas from National Center for Biotechnology Information database were used to search for simple sequence repeats (SSRs). Seven hundred and two sequences containing 786 SSRs with 93.4% simple and 7.6% compound repeat motifs were identified. Dinucleotide repeats (DNRs) were most abundant, followed by trinucleotide and tetranucleotide repeats. AG/CT was the most common motif (50.0%) followed by AT/AT (38.8%) and AC/GT (10.0%) among the DNRs. Four hundred and six primer pairs were designed out of the 702 SSR-containing sequences. Fifty randomly selected EST-SSR markers were amplified in 25 accessions collected from different geographical regions of India. Twenty-one SSR markers were polymorphic and with allele variation from two to four. Polymorphic information content value ranged between 0.04 and 0.61 with an average of 0.25 ± 0.16, indicating low to moderate level of informativeness within these EST-SSRs. The polymorphic markers showed 57.0% to 95.6% transferability among five species of Jatropha and 47.0% transferability across genera in Ricinus communis. Fifty-one alleles detected by the 21 polymorphic EST-SSRs were used to determine genetic relationships among 25 J. curcas accessions. Genetic similarity coefficient ranged from 0.44 to 0.94. The 25 accessions got grouped to three main clusters, comprising 10, 11, and four accessions. This is the first report of development of EST-SSRs in J. curcas and will be valuable resource for future genetical studies, like construction of linkage maps, diversity analysis, quantitative trait locus/association mapping, and molecular breeding of J. curcas. KeywordsBiodiesel plant–Expressed sequence tags–EST-SSRs– Jatropha curcas –Polymorphism–Marker transferability
  Tree Genetics & Genomes 05/2012; 7(1):207-219. · 2.34 Impact Factor
• Article: Recent advances in arsenic accumulation and metabolism in rice

  Rakesh Tuli, Debasis Chakrabarty, Prabodh Kumar Trivedi, Rudra Deo Tripathi
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  ABSTRACT: Arsenic is commonly present in subsoil and is a carcinogen in humans. Rice takes up arsenic and it accumulates in different plant parts, including grains, at levels several-fold higher than the soil. In high arsenic regions, rice can contribute substantially to arsenic intake by the human population. Arsenic in rice grains is present in the carcinogenic inorganic or the relatively safer organic (methylated) form. A wide variation is noticed in different rice genotypes with respect to the proportion of arsenic in these forms in grains. Mechanisms involved in arsenic uptake, efflux from roots, loading into xylem, transport, partitioning, arsenate reduction, arsenic sequestration in vacuoles, volatilization from leaves, accumulation in grains etc. are poorly understood. Selection of cultivars accumulating low inorganic arsenic is an important trait to be used by breeders to develop rice varieties safer for cultivation in arsenic-contaminated regions. Systematic efforts have not been made to screen rice genotypes for mining the genes involved in arsenic uptake, transport and accumulation in grains. Identification of rice germplasm with varying arsenic uptake and partitioning, and development of mapping populations with contrasting grain arsenic, are required for association studies and QTL mapping for accelerating rice improvement. Efforts on gene expression profiling, deep transcriptome sequencing, high throughput metabolomics and phenotyping of contrasting arsenic accumulating lines need to be increased to develop strategies for design of safer rice varieties. Network research projects need to be developed along these approaches to accelerate the development of crop varieties safer for farming in arsenic-contaminated environments. KeywordsArsenic-Quantitative trait loci-Microarray-miRNA-Rice-Stress-Transporters
  Molecular Breeding 04/2012; 26(2):307-323. · 2.85 Impact Factor
• Article: Factors promoting efficient in vitro regeneration from de-embryonated cotyledon explants of Arachis hypogaea L.

  Siddharth Tiwari, Rakesh Tuli
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  ABSTRACT: Highly efficient (>90%) protocols were developed for invitro regeneration from de-embryonated cotyledon explants of peanut (Arachis hypogaea L.). Phytohormone combinations and concentrations, explant source and orientation, period of incubation and the response of genotypes were examined for optimization of the regeneration efficiency. Adventitious shoot primordia could be induced from de-embryonated cotyledon explants when (1) the proximal end of the explant was kept in contact with the shoot induction medium-I supplemented with 5mgl−1BAP+2mgl−1 2,4-D for 4weeks, or (2) the distal end was kept in contact with shoot induction medium-II supplemented with only BAP at 20mgl−1 for the first 2weeks, followed by subculture in the same medium containing 15mgl−1 BAP for the next 2weeks. Orientation of placing the explant on the above media was critical for invitro regeneration. The factors affecting the morphogenic responses like, repetitive organogenesis, shoot elongation, invitro flowering and rhizogenesis were examined. Shoot bud formation was genotype independent. Histological studies showed multicellular origin of adventitious shoot primordia. The protocols gave healthy and fertile plants within 4months.
  Plant Cell Tissue and Organ Culture 04/2012; 92(1):15-24. · 3.09 Impact Factor
• Article: Complete sequence and organisation of the Jatropha curcas (Euphorbiaceae) chloroplast genome

  Mehar H. Asif, Shrikant S. Mantri, Ayush Sharma, Anukool Srivastava, Ila Trivedi, Priya Gupta, Chandra S. Mohanty, Samir V. Sawant, Rakesh Tuli
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  ABSTRACT: Jatropha curcas is an important non-edible oil seed tree species and is considered a promising source of biodiesel. The complete nucleotide sequence of J. curcas chloroplast genome (cpDNA) was determined by pyrosequencing and gaps filled by Sanger sequencing. The cpDNA is a circular molecule of 163,856bp in length and codes for 110 distinct genes (78 protein coding, four rRNA and 28 distinct tRNA). Genome organisation and arrangement are similar to the reported angiosperm chloroplast genome. However, in Jatropha, the infA and the rps16 genes are non-functional. The inverted repeat (IR) boundary is within the rpl2 gene, and the 13 nucleotides at the ends of the two duplicate genes are different. Repeat analysis suggests the presence of 72 repeat regions (>30bp) apart from the IR; of these, 48 were direct and 24 were palindromic repeats. Phylogenetic analysis of 81 protein coding chloroplast genes from 65 taxa by maximum parsimony, maximum likelihood and minimum evolution analyses at 100 bootstraps provide strong support for the placement of inaperturate crotonoids of which Jatropha is a member as sister to articulated crotonoids of which Manihot is a member. Keywords Jatropha curcas -Chloroplast-Genome-Phylogeny-Pyrosequencing-Euphorbiaceae-Angiosperms
  Tree Genetics & Genomes 04/2012; 6(6):941-952. · 2.34 Impact Factor
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  Available from: Pratibha Misra

  Article: Establishment of long-term proliferating shoot cultures of elite Jatropha curcas L. by controlling endophytic bacterial contamination

  Pratibha Misra, Neha Gupta, Dibya D. Toppo, Vibha Pandey, Manoj Kumar Mishra, Rakesh Tuli
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  ABSTRACT: Leaf explants of the second or third node were collected from field-grown elite Jatropha curcas trees and incubated in Murashige and Skoog’s (Physiol Plant 15:473–497, 1962) medium supplemented with growth regulators. Direct shoot organogenesis was induced when explants were incubated in a medium containing 0.5mgl−1 benzyladenine (BA) and 0.1mgl−1 indolebutyric acid (IBA). A maximum of seven shoot buds differentiated within 6weeks of culture incubation. Indirect shoot organogenesis was obtained when explants were incubated in the medium supplemented with 0.5mgl−1 BA along with 1.0mgl−1 each of 2,4-dichlorophenoxyacetic acid (2,4-D) and indoleacetic acid (IAA). A pulse treatment of 0.5mgl−1 thidiazurone (TDZ) and 0.1mgl−1 IBA for 5days was necessary for shoot organogenesis in green compact callus before subculture into 0.5mgl−1 BA and 0.1mgl−1 IBA containing medium. Leaf explants of J. curcas, collected from the field, contained endophytic bacterial contamination, which expressed itself after 2–3 subcultures. These bacteria were cultured and identified as Enterobacter ludwigii. After staining, these were found as gram-negative bacteria. Their sensitivity against different antibiotics has been tested by culturing them with different antibiotic stabs for 72h. Finally, Augmentin® was found as the most effective and suitable antibiotic which not only controlled the bacteria within 2–3 subcultures but also supported the regeneration system and growth of the regenerated shoots and such cultures have been grown for a long-term of over 2years without any contamination.
  Plant Cell Tissue and Organ Culture 04/2012; 100(2):189-197. · 3.09 Impact Factor
• Article: Effect of copy number and spacing of the ACGT and GTcis elements on transient expression of minimal promoter in plants

  Rajesh Mehrotra, Kanti Kiran, Chandra Prakash Chaturvedi, Suraiya Anjum Ansari, Niraj Lodhi, Samir Sawant, Rakesh Tuli
  Journal of Genetics 04/2012; 84(2):183-187. · 1.09 Impact Factor
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  Available from: Sanjay Ranjan

  Article: Genome wide expression profiling of two accession of G. herbaceum L. in response to drought.

  Alok Ranjan, Deepti Nigam, Mehar H Asif, Ruchi Singh, Sanjay Ranjan, Shrikant Mantri, Neha Pandey, Ila Trivedi, Krishan Mohan Rai, Satya N Jena, Bhupendra Koul, Rakesh Tuli, Uday V Pathre, Samir V Sawant
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  ABSTRACT: Genome-wide gene expression profiling and detailed physiological investigation were used for understanding the molecular mechanism and physiological response of Gossypium herbaceum, which governs the adaptability of plants in drought conditions. Recently, microarray-based gene expression analysis is commonly used to decipher genes and genetic networks controlling the traits of interest. However, the results of such an analysis are often plagued due to a limited number of genes (probe sets) on microarrays. On the other hand, pyrosequencing of a transcriptome has the potential to detect rare as well as a large number of transcripts in the samples quantitatively. We used Affymetrix microarray as well as Roche's GS-FLX transcriptome sequencing for a comparative analysis of cotton transcriptome in leaf tissues under drought conditions. Fourteen accessions of Gossypium herbaceum were subjected to mannitol stress for preliminary screening; two accessions, namely Vagad and RAHS-14, were selected as being the most tolerant and most sensitive to osmotic stress, respectively. Affymetrix cotton arrays containing 24,045 probe sets and Roche's GS-FLX transcriptome sequencing of leaf tissue were used to analyze the gene expression profiling of Vagad and RAHS-14 under drought conditions. The analysis of physiological measurements and gene expression profiling showed that Vagad has the inherent ability to sense drought at a much earlier stage and to respond to it in a much more efficient manner than does RAHS-14. Gene Ontology (GO) studies showed that the phenyl propanoid pathway, pigment biosynthesis, polyketide biosynthesis, and other secondary metabolite pathways were enriched in Vagad under control and drought conditions as compared with RAHS-14. Similarly, GO analysis of transcriptome sequencing showed that the GO terms responses to various abiotic stresses were significantly higher in Vagad. Among the classes of transcription factors (TFs) uniquely expressed in both accessions, RAHS-14 showed the expression of ERF and WRKY families. The unique expression of ERFs in response to drought conditions reveals that RAHS-14 responds to drought by inducing senescence. This was further supported by transcriptome analysis which revealed that RAHS-14 responds to drought by inducing many transcripts related to senescence and cell death. The comparative genome-wide gene expression profiling study of two accessions of G.herbaceum under drought stress deciphers the differential patterns of gene expression, including TFs and physiologically relevant processes. Our results indicate that drought tolerance observed in Vagad is not because of a single molecular reason but is rather due to several unique mechanisms which Vagad has developed as an adaptation strategy.
  BMC Genomics 03/2012; 13:94. · 4.07 Impact Factor
• Article: Development and characterization of genomic and expressed SSRs for levant cotton (Gossypium herbaceum L.).

  Satya Narayan Jena, Anukool Srivastava, Krishan Mohan Rai, Alok Ranjan, Sunil K Singh, Tarannum Nisar, Meenal Srivastava, Sumit K Bag, Shrikant Mantri, Mehar Hasan Asif, Hemant Kumar Yadav, Rakesh Tuli, Samir V Sawant
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  ABSTRACT: Four microsatellite-enriched genomic libraries for CA(15), GA(15), AAG(8) and ATG(8) repeats and transcriptome sequences of five cDNA libraries of Gossypium herbaceum were explored to develop simple sequence repeat (SSR) markers. A total of 428 unique clones from repeat enriched genomic libraries were mined for 584 genomic SSRs (gSSRs). In addition, 99,780 unigenes from transcriptome sequencing were explored for 8,900 SSR containing sequences with 12,471 expressed SSRs. The present study adds 1,970 expressed SSRs and 263 gSSRs to the public domain for the use of genetic studies of cotton. When 150 gSSRs and 50 expressed SSRs were tested on a panel of four species of cotton, 68 gSSRs and 12 expressed SSRs revealed polymorphism. These 200 SSRs were further deployed on 15 genotypes of levant cotton for the genetic diversity assessment. This is the first report on the successful use of repeat enriched genomic library and expressed sequence database for microsatellite markers development in G. herbaceum.
  Theoretical and Applied Genetics 02/2012; 124(3):565-76. · 3.30 Impact Factor
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  Available from: Dinesh K Yadav

  Article: Enhanced expression of rabies virus surface G-protein in Escherichia coli using SUMO fusion.

  Ankit Singh, Dinesh Yadav, Krishan Mohan Rai, Meenal Srivastava, Praveen C Verma, Pradhyumna K Singh, Rakesh Tuli
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  ABSTRACT: Fusion systems are known to increase the expression of difficult to express recombinant proteins in soluble form to facilitate their purification. Rabies glycoprotein was also tough to express at sufficient level in soluble form in both E. coli and plant. The present work was aimed to over-express and purify this membrane protein from soluble extract of E. coli. Fusion of Small Ubiqutin like Modifier (SUMO) with rabies glycoprotein increased ~1.5 fold higher expression and ~3.0 fold solubility in comparison to non-fused in E. coli. The SUMO fusion also simplified the purification process. Previously engineered rabies glycoprotein gene in tobacco plants provides complete protection to mice, but the expression was very low for purification. Our finding demonstrated that the SUMO-fusion was useful for enhancing expression and solubility of the membrane protein and again proves to be a good alternative technology for applications in biomedical and pharmaceutical research.
  The Protein Journal 12/2011; 31(1):68-74. · 1.04 Impact Factor
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  Available from: K Chandrashekar

  Article: Compatibility of garlic (Allium sativum L.) leaf agglutinin and Cry1Ac δ-endotoxin for gene pyramiding.

  Santosh Kumar Upadhyay, Seema Singh, Krishnappa Chandrashekar, Rakesh Tuli, Pradhyumna Kumar Singh
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  ABSTRACT: δ-Endotoxins produced by Bacillus thuringiensis (Bt) have been used as bio-pesticides for the control of lepidopteran insect pests. Garlic (Allium sativum L.) leaf agglutinin (ASAL), being toxic to several sap-sucking pests and some lepidopteran pests, may be a good candidate for pyramiding with δ-endotoxins in transgenic plants for enhancing the range of resistance to insect pests. Since ASAL shares the midgut receptors with Cry1Ac in Helicoverpa armigera, there is possibility of antagonism in their toxicity. Our study demonstrated that ASAL increased the toxicity of Cry1Ac against H. armigera while Cry1Ac did not alter the toxicity of ASAL against cotton aphids. The two toxins interacted and increased binding of each other to brush border membrane vesicle (BBMV) proteins and to the two important receptors, alkaline phosphatase (ALP) and aminopeptidase N (APN). The results indicated that the toxins had different binding sites on the ALP and APN but influenced mutual binding. We conclude that ASAL can be safely employed with Cry1Ac for developing transgenic crops for wider insect resistance.
  Applied Microbiology and Biotechnology 08/2011; 93(6):2365-75. · 3.42 Impact Factor
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  Available from: K Chandrashekar

  Article: Purification and characterization of a lectin with high hemagglutination property isolated from Allium altaicum.

  Santosh Kumar Upadhyay, Sharad Saurabh, Rahul Singh, Preeti Rai, Neeraj Kumar Dubey, K Chandrashekar, Kuldeep Singh Negi, Rakesh Tuli, P K Singh
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  ABSTRACT: A lectin was purified from the leaves of Allium altaicum and corresponding gene was cloned. The lectin namely Allium altaicum agglutinin (AAA) was ~24 kDa homodimeric protein and similar to a typical garlic leaf lectin. It was synthesized as 177 amino acid residues pre-proprotein, which consisted of 28 and 43 amino acid long N and C-terminal signal peptides, respectively. The plant expressed this protein more in scapes and flowers in comparison to the bulbs and leaves. Hemagglutination activity (with rabbit erythrocytes) was 1,428 fold higher as compared to Allium sativum leaf agglutinin (ASAL) although, the insecticidal activity against cotton aphid (Aphis gossypii) was relatively low. Glycan array revealed that AAA had higher affinity towards GlcAb1-3Galb as compared to ASAL. Homology analysis showed 57-94% similarity with other Allium lectins. The mature protein was expressed in E. coli as a fusion with SUMO peptide in soluble and biologically active form. Recombinant protein retained high hemagglutination activity.
  The Protein Journal 08/2011; 30(6):374-83. · 1.04 Impact Factor
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  Available from: Santosh Kumar Upadhyay

  Article: A highly stable Cu/Zn superoxide dismutase from Withania somnifera plant: gene cloning, expression and characterization of the recombinant protein.

  Raju Madanala, Vijayta Gupta, Farah Deeba, Santosh Kumar Upadhyay, Vivek Pandey, Pradhyumna Kumar Singh, Rakesh Tuli
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  ABSTRACT: A gene from Withania somnifera (winter cherry), encoding a highly stable chloroplastic Cu/Zn superoxide dismutase (SOD), was cloned and expressed in Escherichia coli. The recombinant enzyme (specific activity of ~4,200 U mg(-1)) was purified and characterized. It retained ~90 and ~70% residual activities after 1 h at 80 and 95 °C, respectively. At 95 °C, thermal inactivation rate constant (K (d)) of the enzyme was 2.46 × 10(-3) min(-1) and half-life of heat inactivation was 4.68 h. The enzyme was stable against a broad pH range (2.5-11.0). It also showed a high degree of resistance to detergent, ethanol and protease digestion. This recombinant Cu/Zn SOD could therefore have useful applications.
  Biotechnology Letters 06/2011; 33(10):2057-63. · 1.68 Impact Factor
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  Available from: Pratibha Misra

  Article: Sterol glycosyltransferases--the enzymes that modify sterols.

  Pankaj Chaturvedi, Pratibha Misra, Rakesh Tuli
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  ABSTRACT: Sterols are important components of cell membranes, hormones, signalling molecules and defense-related biotic and abiotic chemicals. Sterol glycosyltransferases (SGTs) are enzymes involved in sterol modifications and play an important role in metabolic plasticity during adaptive responses. The enzymes are classified as a subset of family 1 glycosyltransferases due to the presence of a signature motif in their primary sequence. These enzymes follow a compulsory order sequential mechanism forming a ternary complex. The diverse applications of sterol glycosides, like cytotoxic and apoptotic activity, anticancer activity, medicinal values, anti-stress roles and anti-insect and antibacterial properties, draws attention towards their synthesis mechanisms. Many secondary metabolites are derived from sterol pathways, which are important in defense mechanisms against pathogens. SGTs in plants are involved in changed sensitivity to stress hormones and their agrochemical analogs and changed tolerance to biotic and abiotic stresses. SGTs that glycosylate steroidal hormones, such as brassinosteroids, function as growth and development regulators in plants. In terms of metabolic roles, it can be said that SGTs occupy important position in plant metabolism and may offer future tools for crop improvement.
  Applied biochemistry and biotechnology 04/2011; 165(1):47-68. · 1.94 Impact Factor
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  Available from: Dinesh K Yadav

  Patent: Chimeric G-protein based rabies vaccine.

  Rakesh Tuli, Samir V Sawant, Shadma Ashraf, Pradhyumna K Singh, Dinesh K Yadav, Md Shahnawaz, Satish Mishra
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  ABSTRACT: A novel chimeric protein of rabies virus designed to express a chimeric G protein at a high level in transgenic plants. A gene was also designed and chemically synthesized to encode the chimeric G protein and expressed at high level in plant tissue. The gene was expressed in transgenic tobacco plants to examine its therapeutic efficacy against infection by rabies virus. The chimeric G protein was enriched in plant membranes. The BalbC mice were immunized with the plant leaf expressed G protein. Plant derived G protein elicited higher immune response as compared to the commercial vaccine. The mice displayed protective immunity when they were challenged with live virus. Chimeric G protein expressed at high level in plants leaves was demonstrated to function as a commercially valuable subunit vaccine against rabies vaccine infection.
  Ref. No: US7901691B2, Year: 03/2011