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101.
Kim DS Paek J Shin JH Kim DW Jung MY Kim RN Sin Y Kook JK Nam SH Kim A Kang A Park HS Choi SH Chang YH 《Journal of bacteriology》2012,194(10):2748-2749
A new Myroides species has been isolated from the urine of a patient with fever in spite of multiple antibiotic treatments who had undergone a radical hysterectomy for cervical cancer and percutaneous nephrostomies for hydronephrosis in the past. The isolate, Myroides injenensis M09-0166(T) (KCTC 23367(T)), showed a high level of resistance to multiple antibiotic agents. Here we provide the first report of the draft genome sequence of a novel species in the genus Myroides within the nonfermenting Gram-negative group. 相似文献
102.
Qiaoping?Qin Quentin?Kaas Chi?Zhang Luping?Zhou Xiaoyan?Luo Mingbing?Zhou Xiaoming?Sun Lanlan?Zhang Kee-Yoeup?Paek Yongyi?CuiEmail author 《Journal of Plant Growth Regulation》2012,31(2):139-155
Massive flowering of tropical Phalaenopsis orchids is coordinated by the cold-induced release of reproductive bud dormancy. Light and temperature are the two key factors
integrated by the dormancy mechanism to both stop and reactivate the meristem development of many other angiosperm species,
including fruit trees and ornamental plants. It is well established that leaves and roots play a major role in inducing flower
development; however, currently, knowledge of molecular events associated with reproductive bud dormancy release in organs
other than the bud is limited. Using differential gene expression, we have shown that the leaves of a hybrid of Phalaenopsis species, Doritaenopsis ‘Tinny Tender’, undergo major metabolic modifications. These changes result in the production of sucrose and amino acids,
both of which can sustain bud outgrowth, and auxin and ethylene, which may play important roles in awaking the dormant buds.
Intake of abscisic acid and synthesis of the hormone jasmonate may also explain the inhibition of vegetative growth that coincides
with bud growth. Interestingly, many genes that were upregulated by cold treatment are homologous for genes involved in flower
induction and vernalization in Arabidopsis, indicating that processes regulating flowering induction and those regulating reproductive bud dormancy release may use
similar pathways and effector molecules. 相似文献
103.
The increasing global demand for biomass of medicinal plant resources reflects the issues and crisis created by diminishing renewable resources and increasing consumer populations. Moreover, diverse usage of plants and reduced land for cultivation in the world accelerated the deficiency of plant resources. In addition, the preparation of safety of plant based medicine whips up demand for biomass of valuable medicinal plants. As one of alternative approach to upswing the productivity of plant-based pharmaceutical compounds, automation of adventitious root culture system in air-lift bioreactor was adopted to produce cosmic amount of root biomass along with enriched diverse bioactive molecules. In this review, various physiological, engineering parameters, and selection of proper cultivation strategy (fed-batch, two-stage etc.) affecting the biomass production and secondary metabolite accumulation have been discussed. In addition, advances in adventitious root cultures including factors for process scale-up as well as recent research aimed at maximizing automation of the bioreactor production processes are also highlighted. Examples of the scale-up of cultures of adventitious roots of Morinda citrifolia, Echinacea purpurea and angustifolia, Hypericum perforatum and Panax ginseng by applying 20L to 10,000L bioreactors in our lab were demonstrated with a view of commercial application. 相似文献
104.
Chitinase is a rate-limiting and endo-splitting enzyme involved in the bio-degradation of chitin, an important component of the cuticular exoskeleton and peritrophic matrix in insects. We isolated a cDNA-encoding chitinase from the last larval integument of the cabbage moth, Mamestra brassicae (Lepidoptera; Noctuidae), cloned the ORF cDNA into E. coli to confirm its functionality, and analyzed the deduced amino acid sequence in comparison with previously described lepidopteran chitinases. M. brassicae chitinase expressed in the transformed E. coli cells with the chitinase-encoding cDNA enhanced cell proliferation to about 1.6 times of the untransformed wild type strain in a colloidal chitin-including medium with only a very limited amount of other nutrients. Compared with the wild type strain, the intracellular levels of chitin degradation derivatives, glucosamine and N-acetylglucosamine were about 7.2 and 2.3 times higher, respectively, while the extracellular chitinase activity was about 2.2 times higher in the transformed strain. The ORF of M. brassicae chitinaseencoding cDNA consisted of 1686 nucleotides (562 amino acid residues) except for the stop codon, and its deduced amino acid composition revealed a calculated molecular weight of 62.7 and theoretical pI of 5.3. The ORF was composed of N-terminal leading signal peptide (AA 1-20), catalytic domain (AA 21-392), linker region (AA 393-498), and C-terminal chitin-binding domain (AA 499-562) showing its characteristic structure as a molting fluid chitinase. In phylogenetic analysis, the enzymes from 6 noctuid species were grouped together, separately from a group of 3 bombycid and 1 tortricid enzymes, corresponding to their taxonomic relationships at both the family and genus levels. 相似文献
105.
Lee HY Park JH Seok SH Baek MW Kim DJ Lee KE Paek KS Lee Y Park JH 《Biochimica et biophysica acta》2006,1761(7):736-744
Many previous studies have reported that conjugated linoleic acid could be produced by starter culture bacteria, but the effects of the bacteria were not investigated. Moreover, there was no evidence of the conjugated linoleic acid-producing bacteria having potential health or nutritional effects related to conjugated linoleic acid, including reducing body fat. Here, we investigated the anti-obesity effect of Lactobacillus rhamnosus PL60, a human originated bacterium that produces t10, c12-conjugated linoleic acid, on diet-induced obese mice. After 8 weeks of feeding, L. rhamnosus PL60 reduced body weight without reducing energy intake, and caused a significant, specific reduction of white adipose tissue (epididymal and perirenal). Although the size of epididymal adipocytes was not reduced by L. rhamnosus PL60, apoptotic signals and UCP-2 mRNA levels increased in adipose tissue. Liver steatosis, a well known side effect of CLA, was not observed by L. rhamnosus PL60 treatment; on the contrary it seemed to be normalized. Results showed that the amount of conjugated linoleic acid produced by Lactobacillus rhamnosus PL60 was enough to produce an anti-obesity effect. 相似文献
106.
Copper-induced changes in the growth, oxidative metabolism, and saponin production in suspension culture roots of Panax ginseng in bioreactors 总被引:3,自引:0,他引:3
Roots of Panax ginseng exposed to various concentrations of Cu (0.0, 5, 10.0, 25.0, and 50.0 μM) accumulated high amounts of Cu in a concentration-dependent and duration-dependent manner. Roots treated with 50 μM Cu resulted in 52% and 89% growth inhibition after 20 and 40 days, respectively. Saponin synthesis was stimulated at a Cu concentration between 5 and 25 μM but decreased at 50 μM Cu. Malondialdehyde content (MDA), lipoxygenase activity (LOX), superoxide ion (O2
•−) accumulation, and H2O2 content at 5 and 10 μM Cu-treated roots were not increased but strongly increased at 50 μM Cu resulting in the oxidation of ascorbate (ASC) and glutathione (GSH) to dehydroascorbate (DHA) and glutathione disulfide (GSSG), respectively indicating a clear oxidative stress. Seven well-resolved bands of superoxide dismutase (SOD) were detected in the gel and an increase in SOD activity seemed to be mainly due to the induction of Fe-SOD 3. Five to 10 μM Cu slightly induced activity of ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR), guaiacol peroxidase (G-POD) but inhibited monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) enzyme activities. No changes in catalase (CAT) activity and in activity gel were found up to 25 μM Cu, but both G-POD and CAT activities were inhibited at 50 μM Cu. Glutathione metabolism enzymes such as γ-glutamylcysteine synthetase (γ-GCS), glutathione-S-transferase (GST), and glutathione peroxidase activities (GPx) were activated at 5 and 10 μM Cu but were strongly inhibited at 50 μM Cu due to the Cu accumulation in root tissues. The strong depletion of GSH at 50 μM Cu was associated to the strong induction of γ-glutamyltranspeptidase (γ-GGT) activity. These results indicate that plant could grow under Cu stress (5–25 μM) by modulating the antioxidant defense mechanism for combating Cu induced oxidative stress. 相似文献
107.
Rice Virescent3 and Stripe1 Encoding the Large and Small Subunits of Ribonucleotide Reductase Are Required for Chloroplast Biogenesis during Early Leaf Development 总被引:7,自引:0,他引:7 下载免费PDF全文
108.
Fu-Nan Li Nam-Jung Kim Seung-Mann Paek Do-Yeon Kwon Kyung Hoon Min Yeon-Su Jeong Sun-Young Kim Young-Ho Park Hee-Doo Kim Hyeung-Geun Park Young-Ger Suh 《Bioorganic & medicinal chemistry》2009,17(10):3557-3567
We have developed a new class of diarylalkyl amides as novel TRPV1 antagonists. They exhibited potent 45Ca2+ uptake inhibitions in rat DRG neuron. In particular, the amide 59 was identified as a potent antagonist with IC50 of 57 nM. The synthesis and structure–activity relationship of the diarylalkyl amides are also described. 相似文献
109.
Senescence is a developmentally regulated and highly ordered sequence of events. Senescence leads to abscission of plant organs
and eventually leads to death of a plant or part of it. Present study revealed that Phalaenopsis flower undergo senescence due to over activation of O2
·−generating xanthine oxidase (XO), which consequently increases the concentrations of O2
·− leading to enhanced oxidative damage and disturbed cellular redox environment as indicated by increased lipid peroxidation
and DHA/AsA + DHA ratio, respectively. While activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and non-specific
peroxidase (POD) were enhanced in sepals and petals of old flower, activities of catalase (CAT) and glutathione reductase
(GR) were decreased. Exogenous application of nitric oxide (NO) retarded H2O2-induced senescence of Phalaenopsis flower by downregulating activity of XO and concentrations of O2
·−, H2O2 and malondialdehyde (MDA, an index of lipid peroxidation). Exogenous application of NO also downregulated SOD activity and
upregulated antioxidant enzymes involved in the detoxification of H2O2 (CAT and APX), and in the regulation of redox couples viz, monodehydroascorbate reductase (MDHAR) and GR, together with the
modulation in non-protein thiol status and DHA/AsA + DHA ratio. 相似文献
110.
C. S. Jeong H. N. Murthy E. J. Hahn H. L. Lee K. Y. Paek 《Acta Physiologiae Plantarum》2009,31(1):219-222
The effect of the root-inoculum size and axuin concentration on growth of adventitious roots and accumulation of ginsenosides
were studied during suspension cultures of ginseng (Panax ginseng C.A. Meyer). Of the various concentrations of indole-3-butyric acid (IBA) and γ-naphthaleneacetic acid (NAA) used as supplementary
growth regulators along with Murashige and Skoog medium, 25 μM IBA was found suitable for lateral root induction and growth,
as well as accumulation of ginsenosides. Inoculum size of 5 g L−1 was found suitable for optimal biomass (10.5 g L−1 dry biomass) and ginsenosides (5.4 mg g−1 DW) accumulation. Of the various length of root inocula tested (chopped to 1–3, 4–6, 7–10 mm and un-chopped), root inocula
of 7–10 mm was found suitable for biomass and ginsenoside accumulation. 相似文献