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211.
Benoit Jacq Thierry Tétu Rajbir S. Sangwan Ad De Laat Brigitte S. Sangwan-Norreel 《Plant cell reports》1992,11(7):329-333
A simple and reproducible protocol for regeneration of sugarbeet plants from hypocotyl expiants derived from 21 day-old-seedlings has been developed. Expiants were cultured on MS medium containing 0.3 mg/l N6-Benzylaminopurine, 0.1 mg/l Naphthalene Acetic Acid, 50 mg/l adenine and 0.5% (w/v) fructose, 0.5% (w/v) sucrose and 0.5% (w/v) glucose to induce the formation of organogenic calli (2.3% to 46.5% organogenic efficiency, depending on populations). Shoot formation was induced in callus cultures of more than 1600 genotypes. Physiological age affected culture response and different genotypes had different temperature optima for organogenesis. Following transfer of regenerated plants to the greenhouse, DNA determinations were made to study the stability of ploidy. Differences in ploidy were observed in plants derived from both shortterm and long-term callus cultures; diploid true-to-type regenerants were 96% and 83%, respectively, from shortterm and long-term callus cultures.Abbreviations MS
Murashige and Skoog medium
- BAP
N6-benzylaminopurine
- IBA
Indolebutyric acid
- NAA
Naphthalene acetic acid
- TIBA
2,3,5 triiodobenzoic Acid
- GM
Germination Medium
- IM
Induction Medium
- RG
Regeneration Medium
- RM
Rooting Medium 相似文献
212.
Kant R van Passel MW Palva A Lucas S Lapidus A Glavina del Rio T Dalin E Tice H Bruce D Goodwin L Pitluck S Larimer FW Land ML Hauser L Sangwan P de Vos WM Janssen PH Smidt H 《Journal of bacteriology》2011,193(11):2902-2903
Chthoniobacter flavus Ellin428 is the first isolate from the class Spartobacteria of the bacterial phylum Verrucomicrobia. C. flavus Ellin428 can metabolize many of the saccharide components of plant biomass but is incapable of growth on amino acids or organic acids other than pyruvate. 相似文献
213.
Parul?Gupta Nehal?Akhtar Shri?Krishna?Tewari Rajender?Singh?Sangwan Prabodh?Kumar?TrivediEmail author 《Plant Growth Regulation》2011,65(1):93-100
Withania somnifera (L.) Dunal (Family, Solanaceae), commonly known as Ashwagandha is one of the most valuable medicinal plants synthesizing
large number of pharmacologically active secondary metabolites known as withanolides. Though the plant has been well characterized
in terms of phytochemical profiles as well as pharmaceutical activities, not much is known about the genes responsible for
biosynthesis of these compounds. In this study, we have characterized a gene encoding farnesyl diphosphate synthase (FPPS;
EC 2.5.1.10), a key enzyme in the pathway of biosynthesis of isoprenoids, from W. somnifera. The full-length cDNA of Withania somnifera FPPS (WsFPPS) of 1,253 bps encodes a polypeptide of 343 amino acids. The amino acid sequence homology and phylogenetic analysis suggest
that WsFPPS has close similarity to its counterparts from tomato (SlFPPS) and capsicum (CaaFPPS). Using semi quantitative RT–PCR, the expression pattern of the WsFPPS gene was analyzed in different tissues of Withania chemotypes (NMITLI-101, NMITLI-108, NMITLI-118 and NMITLI-135) as well as in response to elicitors (salicylic acid and methyl
jasmonate) and mechanical wounding. The expression analysis suggests that WsFPPS expression varies in different tissues (with maximal expression in flower and young leaf) and chemotypes (with highest level
in NMITLI-101) and was significantly elevated in response to salicylic acid, methyl jasmonate and mechanical injury. This
is the first report on characterization of an isoprenoid pathway gene involved in withanolide biosynthesis. 相似文献
214.
Steven M. Swick Joaquin M. Alzola Vinod K. Sangwan Samuel H. Amsterdam Weigang Zhu Leighton O. Jones Natalia Powers‐Riggs Antonio Facchetti Kevin L. Kohlstedt George C. Schatz Mark C. Hersam Michael R. Wasielewski Tobin J. Marks 《Liver Transplantation》2020,10(23)
The synthesis and characterization of new semiconducting materials is essential for developing high‐efficiency organic solar cells. Here, the synthesis, physiochemical properties, thin film morphology, and photovoltaic response of ITN‐F4 and ITzN‐F4, the first indacenodithienothiophene nonfullerene acceptors that combine π‐extension and fluorination, are reported. The neat acceptors and bulk‐heterojunction blend films with fluorinated donor polymer poly{[4,8‐bis[5‐(2‐ethylhexyl)‐4‐fluoro‐2‐thienyl]benzo[1,2‐b:4,5‐b′]‐dithiophene‐2,6‐diyl]‐alt‐[2,5‐thiophenediyl[5,7‐bis(2‐ethylhexyl)‐4,8‐dioxo‐4H,8H‐benzo[1,2‐c:4,5‐c′]dithiophene‐1,3‐diyl]]} (PBDB‐TF, also known as PM6) are investigated using a battery of techniques, including single crystal X‐ray diffraction, fs transient absorption spectroscopy (fsTA), photovoltaic response, space‐charge‐limited current transport, impedance spectroscopy, grazing incidence wide angle X‐ray scattering, and density functional theory level computation. ITN‐F4 and ITzN‐F4 are found to provide power conversion efficiencies greater and internal reorganization energies less than their non‐π‐extended and nonfluorinated counterparts when paired with PBDB‐TF. Additionally, ITN‐F4 and ITzN‐F4 exhibit favorable bulk‐heterojunction relevant single crystal packing architectures. fsTA reveals that both ITN‐F4 and ITzN‐F4 undergo ultrafast hole transfer (<300 fs) in films with PBDB‐TF, despite excimer state formation in both the neat and blend films. Taken together and in comparison to related structures, these results demonstrate that combined fluorination and π‐extension synergistically promote crystallographic π‐face‐to‐face packing, increase crystallinity, reduce internal reorganization energies, increase interplanar π–π electronic coupling, and increase power conversion efficiency. 相似文献
215.
Laxmana Naik Bimlesh Mann Rajesh Bajaj R. B. Sangwan Rajan Sharma 《International journal of peptide research and therapeutics》2013,19(3):231-237
Whey is a protein complex derived from milk, exhibit highest protein quality rating among other proteins, being touted as a functional food with number of health benefits. In the present investigation, whey proteins hydrolysates produced using trypsin enzyme to augment antioxidant activity and to assess angiotensin converting enzyme (ACE) inhibition activity. Hydrolysis parameters were standardized applying response surface methodology. The response antioxidant activity in terms of Trolox equivalent antioxidant capacity (TEAC) values was determined by radical scavenging assay method. Optimum conditions for maximum antioxidant activity were standardized at 88 °C of preheating, 7.3 pH, 0.05 enzymes to substrate ratio and hydrolysis was carried up to 8 h at 36.5 °C. Resulting peptide fractions obtained at 11.8 % of degree of hydrolysis displayed antioxidant capacity with TEAC values of 1.37 ± 0.12. The designed model found to be significant with R2 value of 0.9972 for antioxidant activity and lack of fit test-as non significant, indicating that the optimized conditions were best suited. The hydrolysate further investigated for antihypertensive activity. The outcome indicate that to affect decrease in ACE inhibition activity 4,166.72 μg of native whey protein is required when compared to 229.96 μg of hydrolysates. These results indicate hydrolysate produced under these conditions could be an effective nutraceutical. 相似文献
216.
Nehal Akhtar Parul Gupta Neelam Singh Sangwan Rajender Singh Sangwan Prabodh Kumar Trivedi 《Protoplasma》2013,250(2):613-622
Withania somnifera (L.) Dunal is one of the most valuable medicinal plants synthesizing a large number of pharmacologically active secondary metabolites known as withanolides, the C28-steroidal lactones derived from triterpenoids. Though the plant has been well characterized in terms of phytochemical profiles as well as pharmaceutical activities, not much is known about the biosynthetic pathway and genes responsible for biosynthesis of these compounds. In this study, we have characterized the gene encoding 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR; EC 1.1.1.34) catalyzing the key regulatory step of the isoprenoid biosynthesis. The 1,728-bp full-length cDNA of Withania HMGR (WsHMGR) encodes a polypeptide of 575 amino acids. The amino acid sequence homology and phylogenetic analysis suggest that WsHMGR has typical structural features of other known plant HMGRs. The relative expression analysis suggests that WsHMGR expression varies in different tissues as well as chemotypes and is significantly elevated in response to exposure to salicylic acid, methyl jasmonate, and mechanical injury. The functional color assay in Escherichia coli showed that WsHMGR could accelerate the biosynthesis of carotenoids, establishing that WsHMGR encoded a functional protein and may play a catalytic role by its positive influence in isoprenoid biosynthesis. 相似文献
217.
P.N. Sivalingam D. Singh H.K. Changal Hanif Khan R. Sangwan D.K. Samadia 《Archives Of Phytopathology And Plant Protection》2013,46(3):301-309
A survey was conducted in major chilli-growing hot arid regions of Rajasthan, namely, Bikaner, Nagur, Jodhpur and Jalore districts, during November 2009. Among the four districts surveyed for chilli leaf curl disease (ChLCD), maximum disease incidence was recorded in Jodhpur (98%) followed by Jalore district (88%). The number of whiteflies was also counted in top, middle and bottom leaf of chilli plants grown in these areas. The average number of whiteflies per plant ranged from 0.0 to 4.0. Higher number of whiteflies (4.0) was recorded in Jodhpur and lowest (1.8) in Jalore district. On the basis of conserved region in the genome of begomoviruses infecting chilli, a set of primers was designed to amplify all begomoviruses infecting chilli by PCR; ChCPF 5'-ATTAGGGCTAAGAATTATGTC-3' and ChCPR 5'-AAATTCCAATCTTTATTAATT-3'. These primers were validated by cloning and sequencing (HM004433) of PCR-amplified products and detection from infected chilli leaf samples. These primers were utilised while screening chilli cultivars against begomovirus infection in the asymptomatic plants. Our investigation suggests that the leaf curl disease of chilli is widespread in the hot arid regions of Rajasthan and is caused by a begomovirus associated with a satellite DNA β. The PCR primers designed in this study could be highly useful in chilli breeding programmes. 相似文献
218.
219.
Plant delta-aminolevulinic acid dehydratase. Expression in soybean root nodules and evidence for a bacterial lineage of the Alad gene. 总被引:3,自引:1,他引:2
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We isolated a soybean (Glycine max) cDNA encoding the heme and chlorophyll synthesis enzyme delta-aminolevulinic acid (ALA) dehydratase by functional complementation of an Escherichia coli hemB mutant, and we designated the gene Alad. ALA dehydratase was strongly expressed in nodules but not in uninfected roots, although Alad mRNA was only 2- to 3-fold greater in the symbiotic tissue. Light was not essential for expression of Alad in leaves of dark-grown etiolated plantlets as discerned by mRNA, protein, and enzyme activity levels; hence, its expression in subterranean nodules was not unique in that regard. The data show that soybean can metabolize the ALA it synthesizes in nodules, which argues in favor of tetrapyrrole formation by the plant host in that organ. Molecular phylogenetic analysis of ALA dehydratases from 11 organisms indicated that plant and bacterial enzymes have a common lineage not shared by animals and yeast. We suggest that plant ALA dehydratase is descended from the bacterial endosymbiont ancestor of chloroplasts and that the Alad gene was transferred to the nucleus during plant evolution. 相似文献
220.