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71.
Deepti Barnawal Deepamala Maji Nidhi Bharti Chandan Singh Chanotiya Alok Kalra 《Journal of Plant Growth Regulation》2013,32(4):809-822
This study was aimed at protecting Trigonella plants by reducing stress ethylene levels through ACC (1-aminocyclopropane-1-carboxylic acid) deaminase-containing Bacillus subtilis (LDR2) and promoting plant growth through improved colonization of beneficial microbes like Ensifer meliloti (Em) and Rhizophagus irregularis (Ri) under drought stress. A plant growth-promoting rhizobacterium strain possessing high levels of ACC deaminase characterized as B. subtilis was selected. Application of this strain considerably protected Trigonella plants under severe drought stress conditions; this protection was correlated with reduced levels of ACC (responsible for generation of stress ethylene). The experiment consisted of eight inoculation treatments with different combinations of ACC deaminase-containing rhizobacteria LDR2, Ri, and Em under three water regimes. The tripartite combination of LDR2 + Ri + Em acted synergistically to induce protective mechanisms against decreased soil water availability in Trigonella plants and improved plant weight by 56 % with lower ACC concentration (39 % less than stressed noninoculated plants) under severe drought conditions. Drought-induced changes in biochemical markers like reduced chlorophyll concentration, increased proline content, and higher lipid peroxidation were monitored and clearly indicated the protective effects of LDR2 under drought stress. Under drought conditions, apart from alleviating ethylene-induced damage, LDR2 enhanced nodulation and arbuscular mycorrhizal fungi colonization in the plants resulting in improved nutrient uptake and plant growth. 相似文献
72.
Dhammaprakash Pandhari Wankhede Dipul Kumar Biswas Subramani Rajkumar Alok Krishna Sinha 《Protoplasma》2013,250(6):1239-1249
Podophyllotoxin, an aryltetralin lignan, is the source of important anticancer drugs etoposide, teniposide, and etopophos. Roots/rhizome of Podophyllum hexandrum form one of the most important sources of podophyllotoxin. In order to understand genes involved in podophyllotoxin biosynthesis, two suppression subtractive hybridization libraries were synthesized, one each from root/rhizome and leaves using high and low podophyllotoxin-producing plants of P. hexandrum. Sequencing of clones identified a total of 1,141 Expressed Sequence Tags (ESTs) resulting in 354 unique ESTs. Several unique ESTs showed sequence similarity to the genes involved in metabolism, stress/defense responses, and signalling pathways. A few ESTs also showed high sequence similarity with genes which were shown to be involved in podophyllotoxin biosynthesis in other plant species such as pinoresinol/lariciresinol reductase. A full length coding sequence of pinoresinol/lariciresinol reductase (PLR) has been cloned from P. hexandrum which was found to encode protein with 311 amino acids and show sequence similarity with PLR from Forsythia intermedia and Linum spp. Spatial and stress-inducible expression pattern of PhPLR and other known genes of podophyllotoxin biosynthesis, secoisolariciresinol dehydrogenase (PhSDH), and dirigent protein oxidase (PhDPO) have been studied. All the three genes showed wounding and methyl jasmonate-inducible expression pattern. The present work would form a basis for further studies to understand genomics of podophyllotoxin biosynthesis in P. hexandrum. 相似文献
73.
Mycobacteriosis is a progressive disease of a wide range of wild and captive, marine and freshwater fish species. Conventional detection of fish Mycobacteria is based on histopathology, culture, and biochemical characteristics. The present study analyzed the occurrence of Mycobacteria in clinically ill ornamental fish of different species, from different places of India. In first group, 60 fish were examined for presence of granulomatous inflammation and acid-fast bacteria. Thirty-eight (63.34 %) fish were positive for granulomatous inflammations. Presences of acid-fast bacteria were detected in 27 (45 %) fish having granulomatous inflammation and in two (3.33 %) fish without granulomatous inflammation. In total, AFB were found in 29 (48.34 %) of the 60 fish examined. In second group, 20 fish having granulomatous inflammation, 12 (60 %) samples were positive using Ziehl–Neelsen (Z-N) staining and 11 (55 %) of them were culture positive. Eight (40 %) samples were Z-N negative but two (10 %) of them were culture positive. In total, 13 (65 %) of the 20 examined fish were culture positive. On the basis of biochemical tests and 16S rRNA sequencing, 13 isolates were identified: five as Mycobacterium fortuitum, five as Mycobacterium gordonae, and three as Mycobacterium chelonae. In comparison of two decontamination methods, 2 % HCl treatment was better than 4 % NaOH treatment. Mycobacteria recovery from decontaminated samples was significantly high on Lowenstein–Jensen medium compared to Middlebrook 7H11 agar and Stonebrink (SB) media. The disease is transmissible from fish to fish and also from fish to human, so the significance of Mycobacteria in ornamental fish should not be overlooked. 相似文献
74.
Damien Y. Duveau Xin Hu Martin J. Walsh Suneet Shukla Amanda P. Skoumbourdis Matthew B. Boxer Suresh V. Ambudkar Min Shen Craig J. Thomas 《Bioorganic & medicinal chemistry letters》2013,23(3):682-686
The importance of the trifluoromethyl group in the polypharmacological profile of nilotinib was investigated. Molecular editing of nilotinib led to the design, synthesis and biological evaluation of analogues where the trifluoromethyl group was replaced by a proton, fluorine and a methyl group. While these analogues were less active than nilotinib toward Abl, their activity toward Kit was comparable, with the monofluorinated analogue being the most active. Docking of nilotinib and of analogues 2a–c to the binding pocket of Abl and of Kit showed that the lack of shape complementarity in Kit is compensated by the stabilizing effect from its juxtamembrane region. 相似文献
75.
D. D. Giri P. N. Shukla Singh Ritu Ajay Kumar K. D. Pandey 《World journal of microbiology & biotechnology》2013,29(4):635-643
We analyzed methylotrophs in Bina natural vegetation (BNV), and revegetated overburden dump of four (ROBD4) and 12 years (ROBD12), at Bina coal mine in Sonbhadra district. The cultured strains identified as Pseudomonas, Acinetobacter, Stenotrophomonas and Cellvibrio (γ-Proteobacteria), Methylophilus, Ralstonia, Burkholderia (α-Proteobacteria) Methylobacterium and Inquilinus (β-Proteobacteria), Bacillus (Firmicutes) and Flexibacter (Sphingobacteria) in their 16s rRNA gene sequence similarity. The strains differed in citrate, lactose, formate, urea and xylose utilization. Methanol utilization by Stenotrophomonas, Inquilinus, Cellvibrio and Flexibacter is for first time. The preferred N- sources were proline, glutamate and nitrate for most of the strains. All strains tolerated (2.5 % NaCl) and SDS (0.2 %); 16 strains survived in crystal violet (0.01 %) and nine strains in sodium azide (0.02 %. Methylotrophic population trend was BNV > ROBD12 > ROBD4. The presence of majority of strain of BNV at ROBD12 and ROBD4 indicated restoration of soil methylotrophic functional diversity in revegetated dumps. 相似文献
76.
Atul Tripathi D. K. Mishra Jitendra Kumar Shukla 《Trees - Structure and Function》2013,27(4):1049-1060
A total of 113 Jatropha curcas clonal accessions collected from different regions of India were studied to quantify the magnitude of genetic variability present in the test population and to identify important yield-attributing characters useful for developing high-yielding Jatropha cultivars. High heritability was observed for fruits per plant, seeds per plant, 100-seed weight, seed/kernel (S/K) ratio and kernel oil percentage coupled with high genetic advance suggesting that the accessions can be considered improvement. The significant positive association of seed oil content (%) with 100-seed weight suggested the effectiveness of indirect selection for seed oil content through 100-seed weight. Accessions 76, 120, 29, 86 and 84 showed above average higher values for all yield attributes (viz. fruit and seed yield, 100-seed weight, S/K ratio and oil content) suggesting these as best out of the test accessions. Accessions showing higher values for one or the other yield attributes could be selected as parents for further improvement. 相似文献
77.
Nisha Goyal Praveen Rishi Geeta Shukla 《World journal of microbiology & biotechnology》2013,29(6):1049-1057
The present study describes the in vivo modulatory potential of Lactobacillus rhamnosus GG (LGG), an effective probiotic, in Giardia intestinalis-infected BALB/c mice. Experimentally, it was observed that oral administration of lactobacilli prior or simultaneous with Giardia trophozoites to mice, efficiently (p < 0.05) reduced both the severity and duration of giardiasis. More specifically, probiotics fed, Giardia-infected mice, showed a significant increase in the levels of antioxidants [reduced glutathione (GSH) and superoxide dismutase (SOD)] and intestinal disaccharidases [sucrase and lactase] and decreased levels of oxidants in the small intestine, in comparison with Giardia-infected mice. Histopathological findings also revealed almost normal cellular morphology of the small intestine in probiotic-fed Giardia-infected mice compared with fused enterocytes, villous atrophy and increased infiltration of lymphocytes in Giardia-infected mice. The results of the present study has shed new light on the anti-oxidative properties of LGG in Giardia mediated tissue injury, thereby suggesting that the effects of probiotic LGG are biologically plausible and could be used as an alternative microbial interference therapy. 相似文献
78.
Yu‐Sin Jang Alok Malaviya Joungmin Lee Jung Ae Im Sang Yup Lee Julia Lee Moon‐Ho Eom Jung‐Hee Cho Do Young Seung 《Biotechnology progress》2013,29(4):1083-1088
Butanol is considered as a superior biofuel, which is conventionally produced by clostridial acetone‐butanol‐ethanol (ABE) fermentation. Among ABE, only butanol and ethanol can be used as fuel alternatives. Coproduction of acetone thus causes lower yield of fuel alcohols. Thus, this study aimed at developing an improved Clostridium acetobutylicum strain possessing enhanced fuel alcohol production capability. For this, we previously developed a hyper ABE producing BKM19 strain was further engineered to convert acetone into isopropanol. The BKM19 strain was transformed with the plasmid pIPA100 containing the sadh (primary/secondary alcohol dehydrogenase) and hydG (putative electron transfer protein) genes from the Clostridium beijerinckii NRRL B593 cloned under the control of the thiolase promoter. The resulting BKM19 (pIPA100) strain produced 27.9 g/l isopropanol‐butanol‐ethanol (IBE) as a fuel alcohols with negligible amount of acetone (0.4 g/l) from 97.8 g/l glucose in lab‐scale (2 l) batch fermentation. Thus, this metabolically engineered strain was able to produce 99% of total solvent produced as fuel alcohols. The scalability and stability of BKM19 (pIPA100) were evaluated at 200 l pilot‐scale fermentation, which showed that the fuel alcohol yield could be improved to 0.37 g/g as compared to 0.29 g/g obtained at lab‐scale fermentation, while attaining a similar titer. To the best of our knowledge, this is the highest titer of IBE achieved and the first report on the large scale fermentation of C. acetobutylicum for IBE production. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1083–1088, 2013 相似文献
79.
ABCB1, also known as P-glycoprotein (P-gp) or multidrug resistance protein 1 (MDR1), is a membrane-associated multidrug transporter of the ATP-binding cassette (ABC) transporter family. It is one of the most widely studied transporters that enable cancer cells to develop drug resistance. Reliable high-throughput assays that can identify compounds that interact with ABCB1 are crucial for developing new therapeutic drugs. A high-throughput assay for measuring ABCB1-mediated calcein AM efflux was developed using a fluorescent and phase-contrast live cell imaging system. This assay demonstrated the time- and dose-dependent accumulation of fluorescent calcein in ABCB1-overexpressing KB-V1 cells. Validation of the assay was performed with known ABCB1 inhibitors, XR9576, verapamil, and cyclosporin A, all of which displayed dose-dependent inhibition of ABCB1-mediated calcein AM efflux in this assay. Phase-contrast and fluorescent images taken by the imaging system provided additional opportunities for evaluating compounds that are cytotoxic or produce false positive signals. Compounds with known therapeutic targets and a kinase inhibitor library were screened. The assay identified multiple agents as inhibitors of ABCB1-mediated efflux and is highly reproducible. Among compounds identified as ABCB1 inhibitors, BEZ235, BI 2536, IKK 16, and ispinesib were further evaluated. The four compounds inhibited calcein AM efflux in a dose-dependent manner and were also active in the flow cytometry-based calcein AM efflux assay. BEZ235, BI 2536, and IKK 16 also successfully inhibited the labeling of ABCB1 with radiolabeled photoaffinity substrate [125I]iodoarylazidoprazosin. Inhibition of ABCB1 with XR9576 and cyclosporin A enhanced the cytotoxicity of BI 2536 to ABCB1-overexpressing cancer cells, HCT-15-Pgp, and decreased the IC50 value of BI 2536 by several orders of magnitude. This efficient, reliable, and simple high-throughput assay has identified ABCB1 substrates/inhibitors that may influence drug potency or drug-drug interactions and predict multidrug resistance in clinical treatment. 相似文献
80.
Neeru Singh Praveen K. Bharti Mrigendra P. Singh Sweta Mishra Man M. Shukla Ravendra K. Sharma Rajesh K. Singh 《PloS one》2013,8(3)