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981.
Ga-Young Kang Eun-Hee Park Kyunghoon Kim Chang-Jin Lim 《Journal of microbiology (Seoul, Korea)》2009,47(1):60-67
The structural gene encoding bacterioferritin comigratory protein (Bcp) was amplified using PCR from the genomic DNA of Schizosaccharomyces pombe, and transferred into the shuttle vector pRS316 to generate the recombinant plasmid pBCPlO. The bcp
+ mRNA level in the pBCPlO-containing yeast cells was significantly higher than that in the control yeast cells, indicating
that the cloned gene is functioning. The S. pombe cells harboring the plasmid pBCPIO exhibited higher survival on the solid minimal media with hydrogen peroxide, tert-BOOH or cadmium than the control yeast cells. They also exhibited enhanced cellular viability in the liquid media containing
the stressful agents. The increased viabilities of the fission yeast cells harboring the plasmid pBCP10 were also obtained
with 0.4% glucose or 0.4% sucrose as a sole carbon source, and nitrogen starvation, compared with those of the control yeast
cells. The total glutathione (GSH) content and total GSH/GSSG ratio were significantly higher in the yeast cells harboring
the plasmid pBCP10 than in the control yeast cells. In brief, the S. pombe Bcp plays a protective role in the defensive response to oxidative stress possibly via up-regulation of total and reduced
glutathione levels. 相似文献
982.
We explored to determine if iNOS could be induced by insulin in osteoblast-like UMR-106 cells. Insulin (100 nM) stimulated nitric oxide production by twofold and significantly increased iNOS mRNA and protein levels. Insulin also increased collagen synthesis, but had little effect on alkaline phosphatase activity. In contrast, IGF-1 had little effect on NO production below 10 nM and it stimulated NO production by only 57% at 100 nM. IGF-1 had little effect on collagen levels, whereas it inhibited alkaline phosphatase activities in a dose-dependent manner. When an MEK inhibitor was preincubated, insulin failed to stimulate NO production, whereas insulin dramatically increased NO production in the ERK1 overexpressed cells. Taken together, it is proposed that insulin increases iNOS mRNA, iNOS protein, and NO production, possibly via activation of ERK. These may play an important role in osteoblast functions such as collagen synthesis. 相似文献
983.
Ji-Suk Cho Su-Hwan Chun Song-Jae Lee Ik-Hwan Kim Dong-Il Kim 《Biotechnology and Bioprocess Engineering》2000,5(5):372-378
The cell culture ofAngelica gigas Nakai producing decursin derivatives and immunostimulating polysaccharides was preserved in liquid nitrogen after pre-freezing
in a deep freezer at −70°C for 480 min. The effects of the cryoprotectant and pretreatment before cooling were investigated
to obtain the optimal procedure for cyropreservation. When compared to mannitol, sorbitol, or NaCl with a similar osmotic
pressure, 0.7M sucrose was found to be the best osmoticum for the cryopreservation ofA. gigias cells. In the pre-culture medium, the cells in the exponential growth phase showed the best post-freezing survival after
cryopre-servation. A mixture of sucrose, glycerol, and DMSO was found to be an effective cryoprotectant and a higher concentration
of the cryoprotectant provided better cell viability. When compared with the vitrification, the optimum cryopreservation method
proposed in this study would seem to be more effective for the long-term storage of suspension cells. The highest relative
cell viability established with the optimal procedure was 89%. 相似文献
984.
Bussenius J Anand NK Blazey CM Bowles OJ Bannen LC Chan DS Chen B Co EW Costanzo S DeFina SC Dubenko L Engst S Franzini M Huang P Jammalamadaka V Khoury RG Kim MH Klein RR Laird D Le DT Mac MB Matthews DJ Markby D Miller N Nuss JM Parks JJ Tsang TH Tsuhako AL Wang Y Xu W Rice KD 《Bioorganic & medicinal chemistry letters》2012,22(6):2283-2286
985.
986.
Kurokawa K Kim MS Ichikawa R Ryu KH Dohmae N Nakayama H Lee BL 《Journal of bacteriology》2012,194(13):3299-3306
Bacterial lipoproteins are believed to exist in only one specific lipid-modified structure, such as the diacyl form or the triacyl form, in each bacterium. In the case of Staphylococcus aureus, recent extensive matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry analysis revealed that S. aureus lipoproteins exist in the α-aminoacylated triacyl form. Here, we discovered conditions that induce the accumulation of diacyl lipoproteins that lack α-aminoacylation in S. aureus. The accumulation of diacyl lipoproteins required a combination of conditions, including acidic pH and a post-logarithmic-growth phase. High temperatures and high salt concentrations additively accelerated the accumulation of the diacyl lipoprotein form. Following a post-logarithmic-growth phase where S. aureus MW2 cells were grown at pH 6, SitC lipoprotein was found almost exclusively in its diacyl structure rather than in its triacyl structure. This is the first report showing that the environment mediates lipid-modified structural alterations of bacterial lipoproteins. 相似文献
987.
Background
Restless legs syndrome (RLS) is a sensorimotor neurological disorder characterized by an irresistible urge to move the legs. It has been reported that RLS patients show cognitive deficits, presumably due to hyperactivity causing loss of attention, or malfunctions in the frontal region resulting from sleep deprivation. However, the mechanism underlying cognitive deficits in RLS patients is mostly unknown. As an effort to clarifying this, we investigated the differences in neural activity and phase synchrony between healthy controls and RLS patients during cognitive task performances.Methodology/Principal Findings
Seventeen female drug-naive RLS patients were enrolled in the study, and an age-matched group of thirteen healthy female volunteers served as controls. Multichannel event-related potentials (ERPs) were recorded from RLS patients and normal controls while performing a visual oddball task. In addition to conventional analyses of ERP waveforms and spectra, interregional gamma-band phase synchrony (GBPS) was investigated to observe the differences in interregional neural synchronies between normal and RLS patient groups. Strong GBPS was observed primarily between anterior and posterior regions along the midline for both groups. Along with significant reduction and delay of P300 ERP and induced gamma-band activity (GBA), the GBPS was considerably decreased in RLS patients compared to normal subjects, especially at frontal region.Conclusions
Overall, our results support that cognitive dysfunction in RLS patients is associated with reduced interregional neural synchrony as well as alterations in local neural activity. 相似文献988.
989.
Jung W Lee SG Kang SW Lee YS Lee JH Kang SH Jin ES Kim HJ 《Journal of microbiology and biotechnology》2012,22(7):902-906
Expressed sequence tags (ESTs) from the Antarctic green algae Pyramimonas gelidicola were analyzed to obtain molecular information on cold acclimation of psychrophilic microorganisms. A total of 2,112 EST clones were sequenced, generating 222 contigs and 219 singletons, and 200 contigs and 391 singletons from control (4 degrees C) and cold-shock conditions (-2 degrees C), respectively. The complete EST sequences were deposited to the DDBJ EST database (http:// www.ddbj.nig.ac.jp/index-e.html) and the nucleotide sequences reported in this study are available in the DDBJ/EMBL/ GenBank. These EST databases of Antarctic green algae can be used in a wide range of studies on psychrophilic genes expressed by polar microorganisms. 相似文献
990.
Park CG Kim BJ Kim HY Yun YJ Ko KS Miyamoto H Kim BJ Kook YH 《Microbiology and immunology》2012,56(8):572-578
The population structure of Korean (150 strains) and Japanese (92 strains) Legionella pneumophila isolates along with 18 reference strains were investigated using hsp60 sequence (1647 bp) analysis. Twelve clonal subgroups (hsP-I to hsP-X and hsF-I and hsF-II) were designated on the hsp60 tree, inferred from representative sequences using the neighbor-joining method. Some of the isolates showed unique subgroups depending on the source of isolates, including hsP-I, hsF-I, and hsF-II from cooling tower water, and subgroups hsP-VIII and hsP-X from circulating hot water bath. These subgroups may be useful for epidemiological studies to chase or specify sources of infection in Korea and Japan. 相似文献