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41.
In order to further increase shoot regeneration frequency of Vigna mungo (L.) Hepper., the effects of AgNO3 on this process was investigated in this study. The shoot tip and cotyledonary node explants were cultured on MS salts B5 Vitamins medium containing BA+TDZ+Ads+AgNO3 for multiple shoot induction. AgNO3 influenced the shoot bud formation and their subsequent proliferation. The best medium composition for multiple shoot induction was BA, TDZ combination with Ads and AgNO3 in MSB5 medium. Maximum 39 shoots in cotyledonary node and 22 shoots in shoot tip were obtained per explants after 4 – 6 wk. of culture. Elongation and rooting were performed in GA3 (0.6mg/l) and IBA (0.4mg/L) containing media respectively. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to the field with a survival rate of 78%. 相似文献
42.
Ardra Punnappuzha JagadeeshBabu PonnanEttiyappan Reval Sekhar Nishith Sanjay Hadigal Preethi Ganapathi Pai 《International journal of peptide research and therapeutics》2014,20(4):465-472
Uricase, an enzyme used for the treatment of hyperuricemia, is conjugated with polysialic acid (PSA) of average molecular weight of 10 kDa by reductive amination in presence of NaCNBH3 in order to improve its pharmacological properties. Polysialylation with 50-,100-,150- and 200-fold molar excess of PSA increased the percentage substitution of the free amino groups on enzyme surface (46, 66, 78 and 80 % respectively). The SDS-PAGE is used to visualize the conjugates with increased molecular weight and it retained almost 65 % of their initial specific activity after conjugation. The stability studies at physiological condition reveals improved stability and activity than the native enzyme. The apparent KM of the enzyme has increased slightly from 4.18 × 10?5 M to 5.46 × 10?5 M suggesting that the affinity of the substrate to the enzyme has not been altered to a higher extent. The conjugates, when probed against anti-uricase antibodies generated in rabbit, showed a clean decline in the affinity by 35 % and also have retained double the catalytic activity than that of the native enzyme after exposure to antiserum. The results suggest that uricase-PSA conjugates can be used as an alternative to the conventional synthetic polymer-enzyme conjugates. 相似文献
43.
Two experiments were conducted to determine the effects of protease and phytase (PP) and a Bacillus sp. direct-fed microbial (DFM) on dietary energy and nutrient utilization in broiler chickens. In the first experiment, Ross 308 broiler chicks were fed diets supplemented with PP and DFM in a 2×2 factorial arrangement. The 4 diets (control (CON), CON + PP, CON + DFM, and CON + PP + DFM) were fed from 15–21 days of age. In Experiment 1, significant interaction (P≤0.01) between PP and DFM on the apparent ileal digestibility coefficient for starch, crude protein, and amino acid indicated that both additives increased the digestibility. Both additives increased the nitrogen retention coefficient with a significant interaction (P≤0.01). Although no interaction was observed, significant main effects (P≤0.01) for nitrogen-corrected apparent ME (AMEn) for PP or DFM indicated an additive response. In a follow-up experiment, Ross 308 broiler chicks were fed the same experimental diets from 1–21 days of age. Activities of ileal brush border maltase, sucrase, and L-alanine aminopeptidase were increased (P≤0.01) by PP addition, while a trend (P = 0.07) for increased sucrase activity was observed in chickens fed DFM, in Experiment 2. The proportion of cecal butyrate was increased (P≤0.01) by DFM addition. Increased nutrient utilization and nitrogen retention appear to involve separate but complementary mechanisms for PP and DFM, however AMEn responses appear to have separate and additive mechanisms. 相似文献
44.
Vengadesan G. Ganapathi A. Prem Anand R. Ramesh Anbazhagan V. 《Plant Cell, Tissue and Organ Culture》2000,61(1):23-28
In vitro morphogenesis via organogenesis was achieved from callus cultures derived from hypocotyl explants of Acacia sinuata on MS (Murashige and Skoog, 1962) medium. Calli were induced from hypocotyl explants excised from 7-day-old seedlings on
MS medium containing 3% sucrose, 0.8% agar, 6.78 μM 2,4-dichlorophenoxyacetic acid and 2.22 μM 6-benzylaminopurine. Regeneration
of adventitious buds from callus was achieved when they were cultured on MS medium supplemented with 10% coconut water, 13.2
μM 6-benzylaminopurine and 3.42 μM indoleacetic acid. Addition of gibberellic acid (1.73 μM) favored shoot elongation. Regenerated
shoots produced prominent roots when transferred to half strength MS medium supplemented with 7.36 μM indolebutyric acid.
Rooted plantlets, thus developed were hardened and successfully established in the soil. This protocol yielded an average
of 20 plants per hypocotyl explant over a period of 4 months.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
45.
John H. Huffman Robert W. Sidwell Roland K. Robins Ganapathi R. Revankar Dominique Y. Pifat 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):1159-1160
Abstract Eleven compounds were compared to ribavirin for their in vitro and in vivo inhibition of Punta Toro virus (PTV), a phlebovirus in the Bunyaviridae virus family. 相似文献
46.
The selected NaCl tolerant clones ofMorus alba L. cv. MR2 grow better at higher concentration of NaCl than non-selected clones. With increasing NaCl concentration the Na+, Cl? and proline content increased more and K+ and Ca2+ content decrease less in selected clones in comparison with non-selected ones. 相似文献
47.
Evolution of eutherian cytochrome c oxidase subunit II: heterogeneous rates of protein evolution and altered interaction with cytochrome c 总被引:3,自引:1,他引:2
Cytochrome c oxidase subunit II (COII), encoded by the mitochondrial
genome, exhibits one of the most heterogeneous rates of amino acid
replacement among placental mammals. Moreover, it has been demonstrated
that cytochrome c oxidase has undergone a structural change in higher
primates which has altered its physical interaction with cytochrome c. We
collected a large data set of COII sequences from several orders of mammals
with emphasis on primates, rodents, and artiodactyls. Using phylogenetic
hypotheses based on data independent of the COII gene, we demonstrated that
an increased number of amino acid replacements are concentrated among
higher primates. Incorporating approximate divergence dates derived from
the fossil record, we find that most of the change occurred independently
along the New World monkey lineage and in a rapid burst before apes and Old
World monkeys diverged. There is some evidence that Old World monkeys have
undergone a faster rate of nonsynonymous substitution than have apes. Rates
of substitution at four-fold degenerate sites in primates are relatively
homogeneous, indicating that the rate heterogeneity is restricted to
nondegenerate sites. Excluding the rate acceleration mentioned above,
primates, rodents, and artiodactyls have remarkably similar nonsynonymous
replacement rates. A different pattern is observed for transversions at
four-fold degenerate sites, for which rodents exhibit a higher rate of
replacement than do primates and artiodactyls. Finally, we hypothesize
specific amino acid replacements which may account for much of the
structural difference in cytochrome c oxidase between higher primates and
other mammals.
相似文献
48.
Molecular evolution of cytochrome c oxidase: rate variation among subunit VIa isoforms 总被引:3,自引:1,他引:2
Schmidt TR; Jaradat SA; Goodman M; Lomax MI; Grossman LI 《Molecular biology and evolution》1997,14(6):595-601
Cytochrome c oxidase (COX) consists of 13 subunits, 3 encoded in the
mitochondrial genome and 10 in the nucleus. Little is known of the role of
the nuclear-encoded subunits, some of which exhibit tissue-specific
isoforms. Subunit VIa is unique in having tissue-specific isoforms in all
mammalian species examined. We examined relative evolutionary rates for the
COX6A heart (H) and liver (L) isoform genes along the length of the
molecule, specifically in relation to the tissue-specific function(s) of
the two isoforms. Nonsynonymous (amino acid replacement) substitutions in
the COX6AH gene occurred more frequently than in the ubiquitously expressed
COX6AL gene. Maximum-parsimony analysis and sequence divergences from
reconstructed ancestral sequences revealed that after the ancestral COX6A
gene duplicated to yield the genes for the H and L isoforms, the sequences
encoding the mitochondrial matrix region of the COX VIa protein experienced
an elevated rate of nonsynonymous substitutions relative to synonymous
substitutions. This is expected for relaxed selective constraints after
gene duplication followed by purifying selection to preserve the
replacements with tissue-specific functions.
相似文献
49.
Induction of C-reactive protein by cytokines in human hepatoma cell lines is potentiated by caffeine.
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M K Ganapathi A Mackiewicz D Samols A Brabenec I Kushner D Schultz S I Hu 《The Biochemical journal》1990,269(1):41-46
Progesterone 5 alpha-reductase, which catalyses the reduction of progesterone to 5 alpha-pregnane-3,20-dione, was isolated and characterized from cell cultures of Digitalis lanata (foxglove). Optimum enzyme activity was observed at pH 7.0, and the enzyme had an apparent Km value of 30 microM for its substrate progesterone. The enzyme needs NADPH as reductant, which could not be replaced by NADH. For NADPH, the apparent Km value is 130 microM. The optimum temperature was 40 degrees C; at temperatures below 45 degrees C, the product 5 alpha-pregnane-3,20-dione was reduced by a second reaction to 5 alpha-pregnan-3 beta-ol-20-one. Progesterone 5 alpha-reductase activity was not dependent on bivalent cations. In the presence of EDTA, 0.1 mM-Mn2+ had no influence on enzyme activity, whereas 0.1 mM-Ca2+, -Co2+ and -Zn2+ decreased progesterone 5 alpha-reductase activity. Only 0.1 mM-Mg2+ was slightly stimulatory. EDTA and thiol reagents such as dithiothreitol stimulate progesterone 5 alpha-reductase activity. By means of linear sucrose gradient fractionation of the cellular membranes, progesterone 5 alpha-reductase was found to be located in the endoplasmic reticulum. 相似文献
50.
There is a growing interest to develop oral vaccines for infectious diseases, as it is the most convenient and effective way to attain mucosal immunity. Hepatitis B continues to be a major infectious disease in many developing countries despite the availability of recombinant vaccine. On a global scenario, Hepatitis B Virus infection is probably the single most prevalent cause of persistent viraemia in humans. There are about 350 million chronic carriers of HBV, which is about 5% of the total world population. It is estimated that 75-100 million of them will die of liver cirrhosis and/or hepatocellular carcinoma. Progress in plant genetic engineering has enabled the transfer of useful genes for desirable traits. The recent trend is to use this technique to exploit plants as biofactories for the production of therapeutic proteins including vaccines. Rapid progress has been made in this area to develop plant-based vaccines for hepatitis B. This review describes the expression, characterization, and immunogenicity studies of hepatitis B vaccines produced in recombinant plant systems and their implications for developing a plant-based vaccine. 相似文献