@article { ISI:000259484700016, title = {Direct shoot organogenesis and plant regeneration from hypocotyl explants in selected genotypes of Leucaena leucocephala - a leguminous pulpwood tree}, journal = {Indian Journal of Biotechnology}, volume = {7}, number = {3}, year = {2008}, month = {JUL}, pages = {388-393}, publisher = {NATL INST SCIENCE COMMUNICATION-NISCAIR}, type = {Article}, address = {DR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIA}, abstract = {

An efficient in vitro plant regeneration system in subabul (Leucaena leucocephala), a leguminous pulp wood tree species, was established. The induction of shoots was achieved from selected elite clones of subabul K-8, K-636 and also wild type on MS medium supplemented with 2\% sucrose and different concentrations (0.88 to 24.6 mu M) of plant growth regulators (BA, Kn, 2iP \& TDZ). The best medium for shoot regeneration was MS with 22.2 mu M BA (5 shoots per explant), followed by 22.7 mu M TDZ (4.6 shoots per explant). Addition of putriscine (9.3 mu M) to MS medium containing 22.2 mu M BA enhanced the number of multiple shoots to 7-8 but not the frequency of response. Shoot initials (measuring 1 cm) when separated and transferred on to MS medium containing 1.4 mu M GA(3) elongated to 2-5 cm in 15.20 d with 80\% frequency. The per cent frequency of shoot differentiation was almost identical in the genotypes K-8 and K-636 but it differed significantly from the wild type. Leaf yellowing and abscission in all the genotypes was curtailed by supplementing the medium with 685 mu M glutamine or 540 mu M adenine. The excised shoots were transferred to root regeneration media containing 2.46 and 4.98 mu M IBA or 2.6 and 5.3 mu M NAA. Root regeneration was noticed with 100\% frequency in all the three genotypes in presence of IBA or NAA. Plantlets were transferred successfully to the pots with 70\% survival rate with no visible morphological variations. The protocol can be utilized for mass propagation and genetic transformation studies of this important pulpwood species.

}, keywords = {hypocotyl explants, Leucaena lucocephala, pulpwood leguminous tree, shoot organogenesis}, issn = {0972-5849}, author = {Sirisha, V. L. and Prashant, S. and Ranadheer, D. and Ramprasad, P. and Shaik, N. M. and Arha, Manish and Gupta, S. K. and Srivastava, Sarneer and Yadav, A. K. and Kulkarni, P. S. and Othalathara U. Abhilash and Khan, Bashir Mohammad and Rawal, Shuban K. and Kishor, P. B. Kavi} } @article { ISI:000262435000012, title = {Phylogenetic analysis, homology modelling, molecular dynamics and docking studies of caffeoyl-CoA-O- methyl transferase (CCoAOMT 1 and 2) isoforms isolated from subabul (Leucaena leucocephala)}, journal = {Journal of Molecular Modeling}, volume = {15}, number = {2}, year = {2009}, month = {FEB}, pages = {203-221}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) is an important enzyme that participates in lignin biosynthesis especially in the formation of cell wall ferulic esters of plants. It plays a pivotal role in the methylation of the 3-hydroxyl group of caffeoyl CoA. Two cDNA clones that code CCoAOMT were isolated earlier from subabul and in the present study; 3D models of CCoAOMT1 and CCoAOMT2 enzymes were built using the MODELLER7v7 software to find out the substrate binding sites. These two proteins differed only in two amino acids and may have little or no functional redundancy. Refined models of the proteins were obtained after energy minimization and molecular dynamics in a solvated water layer. The models were further assessed by PROCHECK, WHATCHECK, Verify_3D and ERRAT programs and the results indicated that these models are reliable for further active site and docking analysis. The refined models showed that the two proteins have 9 and 10 alpha-helices, 6 and 7 beta-sheets respectively. The models were used for docking the substrates CoA, SAM, SAH, caffeoyl CoA, feruloyl CoA, 5-hydroxy feruloyl CoA and sinapyl CoA which showed that CoA and caffeoyl CoA are binding with high affinity with the enzymes in the presence and absence of SAM. It appears therefore that caffeoyl CoA is the substrate for both the isoenzymes. The results also indicated that CoA and caffeoyl CoA are binding with higher affinity to CCoAOMT2 than CCoAOMT1. Therefore, CCoAOMT2 conformation is thought to be the active form that exists in subabul. Docking studies indicated that conserved active site residues Met58, Thr60, Val63, Glu82, Gly84, Ser90, Asp160, Asp162, Thr169, Asn191 and Arg203 in CCoAOMT1 and CCoAOMT2 enzymes create the positive charge to balance the negatively charged caffeoyl CoA and play an important role in maintaining a functional conformation and are directly involved in donor-substrate binding.

}, keywords = {Caffeoyl-CoA 3-O-methyl transferase, docking, Modelling, S-adenosyl homocysteine}, issn = {1610-2940}, doi = {10.1007/s00894-008-0395-8}, author = {Pagadala, Nataraj Sekhar and Arha, Manish and Reddy, P. S. and Kumar, Ranadheer and Sirisha, V. L. and Prashant, S. and Reddy, K. Janardhan and Khan, Bashir Mohammad and Rawal, S. K. and Kishor, P. B. Kavi} } @article { ISI:000276010000034, title = {Cytotoxic activity of 9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol from Eulophia nuda against human cancer cells}, journal = {Journal of Ethnopharmacology}, volume = {128}, number = {1}, year = {2010}, month = {MAR}, pages = {251-253}, publisher = {ELSEVIER IRELAND LTD}, address = {ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND}, abstract = {

Ethnopharmacological relevance: Eulophia nuda L. (Orchidaceae) is a medicinally important terrestrial orchid used for the treatment of tumours and various health problems by the local healers throughout the Western Ghats region in Maharashtra (India). Aim of the study: To isolate the active molecule from Eulophia nuda and to study its cytotoxic potential against human cancer cells. Materials and methods: The crude methanolic extract of Eulophia nuda tubers was fractionated by stepwise gradient of the solvents chloroform-methanol to isolate the pure compound. Isolated pure compound was assessed for its cytotoxic potential against human breast cancer cell lines, MCF-7 and MDA-MB-231 using MTT assay. Structure elucidation of the isolated active compound was carried out by extensive spectroscopic analysis including (1)H NMR, (13)C NMR, NOESY, COSY, LC-MS and IR. Results: The isolated active molecule was identified as phenanthrene derivative 9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol. This compound showed good antiproliferative activity against human breast cancer cell lines MCF-7 (91\%) and MDA-MB-231 (85\%) at 1000 mu g/ml concentration. Conclusion: 9,10-Dihydro-2,5-dimethoxyphenanthrene-1,7-diol from Eulophia nuda tubers showed good growth suppressive effect against human cancer cell lines MCF-7 and MDA-MB-231 making it a potential biomolecule against human cancer. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

}, keywords = {Cytotoxic activity, Eulophia nuda, Phenanthrene derivatives}, issn = {0378-8741}, doi = {10.1016/j.jep.2009.12.031}, author = {Shriram, Varsha and Kumar, Vinay and Kishor, P. B. Kavi and Suryawanshi, Sharad B. and Upadhyay, Ankur K. and Bhat, Manoj K.} } @article { ISI:000287716400004, title = {Expression analysis of cinnamoyl-CoA reductase (CCR) gene in developing seedlings of Leucaena leucocephala: A pulp yielding tree species}, journal = {Plant Physiology and Biochemistry}, volume = {49}, number = {2}, year = {2011}, month = {FEB}, pages = {138-145}, publisher = {ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER}, address = {23 RUE LINOIS, 75724 PARIS, FRANCE}, abstract = {

Removal of lignin is a major hurdle for obtaining good quality pulp. Leucaena leucocephala (subabul) is extensively used in paper industry in India; therefore, as a first step to generate transgenic plants with low lignin content, cDNA and genomic clones of CCR gene were isolated and characterized. The cDNA encoding CCR (EC 1.2.1.44) was designated as LI-CCR; the sequence analysis revealed an Open Reading Frame (ORF) of 1005 bp. Phylogenetic analysis showed that LI-CCR sequence is highly homologous to CCRs from other dicot plants. The 2992 bp genomic clone of Leucaena CCR consists of 5 exons and 4 introns. The haploid genome of L leucocephala contains two copies as revealed by DNA blot hybridization. LI-CCR gene was over-expressed in Escherichia coli, which showed a molecular mass of approximately 38 kDa. Protein blot analysis revealed that LI-CCR protein is expressed at higher levels in root and in stem, but undetectable in leaf tissues. Expression of CCR gene in Leucaena increased up to 15 d in case of roots and stem as revealed by QRT-PcR studies in 0-15 d old seedlings. ELISA based studies of extractable CCR protein corroborated with QRT-PCR data. CCR protein was immuno-cytolocalized around xylem tissue. Lignin estimation and expression studies of 5,10 and 15 d old stem and root suggest that CCR expression correlates with quantity of lignin produced, which makes it a good target for antisense down regulation for producing designer species for paper industry. (C) 2010 Elsevier Masson SAS. All rights reserved.

}, keywords = {Cinnamoyl-CoA reductase, Developing seedling, Leucaena leucocephala, Lignin biosynthesis}, issn = {0981-9428}, doi = {10.1016/j.plaphy.2010.11.001}, author = {Srivastava, Sameer and Gupta, Ranadheer K. and Arha, Manish and Vishwakarma, Rishi K. and Rawal, Shuban K. and Kishor, P. B. Kavi and Khan, Bashir Mohammad} } @article { ISI:000302573400003, title = {Cloning, characterization and impact of up- and down-regulating subabul cinnamyl alcohol dehydrogenase (CAD) gene on plant growth and lignin profiles in transgenic tobacco}, journal = {Plant Growth Regulation}, volume = {66}, number = {3}, year = {2012}, month = {APR}, pages = {239-253}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

Both cDNA including 5{\textquoteright}UTR and 3{\textquoteright}UTR and genomic clones of cinnamyl alcohol dehydrogenase (CAD) were isolated and characterized from a pulp-yielding leguminous tree Leucaena leucocephala (LlCAD1). The deduced amino acid sequence shared high identity with orthologous sequences of Acacia mangium x Acacia auriculiformis (83\%), Medicago sativa (83\%), Nicotiana tabaccum (83\%) and Aralia cordata (81\%). Full length cDNA contained 78 bases of 5{\textquoteright}UTR and 283 bases of 3{\textquoteright}UTR, while the genomic clone contained 5 exons and 4 introns. Western blot analysis revealed elevated expression of LlCAD1 in seedling roots and shoots compared to leaves. Sense and antisense CAD tobacco transgenics showed increased and reduced CAD activity accompanied by a change in monomeric lignin composition. Histochemical staining of lignin in down-regulated plants suggested an increase in aldehyde units and a decrease in S/G ratio. Down-regulation of CAD resulted in accumulation of syringic, ferulic, p-coumaric and sinapic acids compared to untransformed controls. These observations were validated by anatomical studies of down-regulated transgenic stems which showed thin walled, elongated phloem and xylem fibres, accompanied by a reduction in the density of vessel elements and amount of secondary xylem when compared to untransformed plants. Furthermore, Klason lignin analysis of CAD antisense transgenics showed 7-32\% reduced lignin and normal phenotype as compared to untransformed plants. Such a reduction was not noticed in up-regulated transgenics. These results demonstrate a unique opportunity to explore the significant role that down-regulation of CAD gene plays in reducing lignin content thereby offering potential benefits to the pulp and paper industry.

}, keywords = {Cinnamyl alcohol dehydrogenase, Lignin down-regulation, Subabul (Leucaena leucocephala), Tobacco}, issn = {0167-6903}, doi = {10.1007/s10725-011-9647-1}, author = {Sirisha, V. L. and Prashant, S. and Kumar, D. Ranadheer and Pramod, S. and Jalaja, N. and Kumari, P. Hima and Rao, P. Maheshwari and Rao, S. Nageswara and Mishra, Preeti and Karumanchi, S. Rao and Khan, Bashir Mohammad and Kishor, P. B. Kavi} }