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991.
Lee C Chung KW Kim TS Choi KM Choi YK Chung NJ Rhie HG Lee HS Lee SJ Lee HW 《Experimental parasitology》2011,129(3):227-233
Merozoite surface protein-1 (MSP-1), a major asexual blood stage antigen, and circumsporozoite protein (CSP), a component of sporozoites that includes a Plasmodium vivax B-cell epitope, are strong candidates for use in a malaria vaccine. A chimeric recombinant gene containing portions of both msp-1 and csp from P. vivax separated by Pro-Gly linker motif was generated. The construct gene was named mlc (msp-1, linker, and csp). The MLC chimeric recombinant protein had a molecular weight of approximately 25 kDa when expressed in Escherichia coli, as determined with sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) analysis. The purified chimeric protein reacted with the sera of patients infected with P. vivax but not with the sera of uninfected patients according to western blot analysis. The chimeric protein reacted well with sera of malaria patients (109/115, 94.78%) as assessed with enzyme-linked immunosorbent assay (ELISA). BALB/c mice that were orally immunized with the MLC chimeric recombinant protein successfully produced antigen-specific antibodies. Additionally, levels of the Th1-associated cytokines IL-12(p40), TNF-α, and IFN-γ were significantly increased in the spleens of the BALB/c mice. Therefore, the E. coli-expressed MLC chimeric recombinant protein might be used as a valuable vaccine candidate for oral immunization against vivax malaria. 相似文献
992.
Jang SI Lillehoj HS Lee SH Lee KW Lillehoj EP Bertrand F Dupuis L Deville S 《Experimental parasitology》2011,127(1):36-41
Leishmaniasis is a disease caused by the unicellular Leishmania parasite. World wide millions of people are affected by this vector born disease. The disease presents itself in different clinical manifestations which are caused by specific Leishmania species. The therapeutic strategy depends on the Leishmania species involved. It is important to detect Leishmania and subsequently type the infecting species in a sensitive way using PCR. Various targets have been proposed but two seem to be best suited, the ITS1 region and the mini-exon. There is, however, no consensus as to which of these two is best. The aim of this study was to compare both targets with our current method, a PCR on the 18S ribosomal RNA gene. The ITS1 PCR proved to be slightly more sensitive and more practical than the mini-exon. Nevertheless, the mini-exon is more polymorphic and is needed in subtyping Leishmania species belonging to the L. Viannia subgenus. The ITS1 method was adapted to use as a real-time PCR for diagnostic purposes. In addition, designing and testing a new primer set improved sensitivity of the PCR on the mini-exon. 相似文献
993.
Chi SW Jeong DG Woo JR Lee HS Park BC Kim BY Erikson RL Ryu SE Kim SJ 《FEBS letters》2011,585(4):664-670
Heat shock protein 33 (Hsp33) from Escherichia coli is a redox-regulated molecular chaperone that protects cells from oxidative stress. To understand the molecular basis for the monomer-dimer switch in the functional regulation of E. coli Hsp33, we generated a constitutively monomeric Hsp33 by introducing the Q151E mutation in the dimeric interface and determined its crystal structure. The overall scaffold of the monomeric Hsp33(1-235) (Q151E) mutant is virtually the same as that of the dimeric form, except that there is no domain swapping. The measurement of chaperone activity to thermally denatured luciferase showed that the constitutively monomeric Hsp33 mutant still retains chaperone activity similar to that of wild-type Hsp33(1-235), suggesting that a Hsp33 monomer is sufficient to interact with slowly unfolded substrate. 相似文献
994.
Corynebacterium nuruki S6-4(T), isolated from Korean alcohol fermentation starter, is a strictly aerobic, nonmotile, Gram-positive, and rod-shaped bacterium belonging to the genus Corynebacterium and the actinomycete group. We report here the draft genome sequence of C. nuruki strain S6-4(T) (3,106,595 bp, with a G+C content of 69.5%). 相似文献
995.
Lee JH Chae JP Lee JY Lim JS Kim GB Ham JS Chun J Kang DK 《Journal of bacteriology》2011,193(18):5030-5031
Lactobacillus johnsonii PF01, an autochthonous bacterium of the gastrointestinal tract, was isolated from a fecal sample from a piglet. The strain adhered specifically to the duodenal and jejunal epithelial cells of the piglet and had high bile resistance activity. Here we report the genomic sequence of L. johnsonii PF01. 相似文献
996.
Charles Margraves Kenneth Kihm Sang Youl Yoon Chang Kyoung Choi Seong‐ho Lee Jason Liggett Seung Joon Baek 《Biotechnology and bioengineering》2011,108(10):2504-2508
Intracellular vesicles, comprised of protein clusters, were individually tracked inside human brain cancer cells and characterized to simultaneously determine the average vesicle size and effective cytoplasmic viscosity. The cells were transfected with a TGF‐β superfamily gene, non‐steroidal anti‐inflammatory drug‐Activated Gene‐1 (NAG‐1) tagged with green fluorescent proteins (GFPs). Using total internal reflection fluorescent microscopy (TIRFM) the individual movements of the vesicles were categorized into either Brownian, caged, or directional type motion. In the near‐field region confined by the evanescent wave field of TIRFM, the hindrance of these vesicles was created by interactions with the glass coverslip and/or sub‐cellular structures. Measured particle motions were compared with theoretical predictions of hindered motion to estimate the unknown size and viscosity parameters using a nonlinear regression technique. For the tested human brain cancer cells, the average vesicle size and effective intracellular fluid viscosity were calculated to be 496 nm and 0.068 Pa s, respectively. This finding suggests that most of the hindrance experienced by vesicles can be due to non‐hydrodynamic interactions with microtubules and other intracellular structures. It should be also noted that this method provides a way to examine changes in vesicle size due to outside stimulus such as drug interaction, cytotoxicity, etc., unlike standard measurement techniques which require fixing the cells themselves. Biotechnol. Bioeng. 2011;108: 2504–2508. © 2011 Wiley Periodicals, Inc. 相似文献
997.
998.
Park EJ Kim KH Abell GC Kim MS Roh SW Bae JW 《Applied and environmental microbiology》2011,77(4):1284-1291
Viruses are recognized as the most abundant biological components on Earth, and they regulate the structure of microbial communities in many environments. In soil and marine environments, microorganism-infecting phages are the most common type of virus. Although several types of bacteriophage have been isolated from fermented foods, little is known about the overall viral assemblages (viromes) of these environments. In this study, metagenomic analyses were performed on the uncultivated viral communities from three fermented foods, fermented shrimp, kimchi, and sauerkraut. Using a high-throughput pyrosequencing technique, a total of 81,831, 70,591 and 69,464 viral sequences were obtained from fermented shrimp, kimchi and sauerkraut, respectively. Moreover, 37 to 50% of these sequences showed no significant hit against sequences in public databases. There were some discrepancies between the prediction of bacteriophages hosts via homology comparison and bacterial distribution, as determined from 16S rRNA gene sequencing. These discrepancies likely reflect the fact that the viral genomes of fermented foods are poorly represented in public databases. Double-stranded DNA viral communities were amplified from fermented foods by using a linker-amplified shotgun library. These communities were dominated by bacteriophages belonging to the viral order Caudovirales (i.e., Myoviridae, Podoviridae, and Siphoviridae). This study indicates that fermented foods contain less complex viral communities than many other environmental habitats, such as seawater, human feces, marine sediment, and soil. 相似文献
999.
The most prevalent disease-causing mutation of CFTR is the deletion of Phe508 (ΔF508), which leads to defects in conventional Golgi-mediated exocytosis and cell surface expression. We report that ΔF508-CFTR surface expression can be rescued in vitro and in vivo by directing it to an unconventional GRASP-dependent secretion pathway. An integrated molecular and physiological analysis indicates that mechanisms associated with ER stress induce cell surface trafficking of the ER core-glycosylated wild-type and ΔF508-CFTR via the GRASP-dependent pathway. Phosphorylation of a specific site of GRASP and the PDZ-based interaction between GRASP and CFTR are critical for this unconventional surface trafficking. Remarkably, transgenic expression of GRASP in ΔF508-CFTR mice restores CFTR function and rescues mouse survival without apparent toxicity. These findings provide insight into how unconventional protein secretion is activated, and offer a potential therapeutic strategy for the treatment of cystic fibrosis and perhaps diseases stemming from other misfolded proteins. 相似文献
1000.
Yi SS Hwang IK Kim DW Shin JH Nam SM Choi JH Lee CH Won MH Seong JK Yoon YS 《Neurochemical research》2011,36(1):117-128
Because it appears that oxidative stress and inflammation are implicated with disease pathogenesis in the diabetic brain,
many researchers have used streptozotocin (STZ)-induced diabetic animals to study superoxide production and the effects of
superoxide scavengers like Cu,Zn-superoxide dismutase (SOD1). However, many studies have been conducted without considering
temporal changes after STZ injection. Interestingly, though SOD activities were not significantly different among the groups,
SOD1 and 4-hydroxy-2-nonenal (4-HNE) immunoreactivities were significantly enhanced at 3 weeks after an STZ injection (STZ3w)
versus only marginal levels in sham controls, whereas microglial activity was remarkably reduced in injected rats at this
time. However, SOD1 immunoreactivity and microglial activities were only at the sham level at STZ4w. The present study provides
important information concerning cell damage by ROS generated by STZ. Microglial response was found to be inactivated at STZ3w
and neuronal cells (NeuN) showed a non-significant tendency to be reduced in number at STZ4w except in the dentate gyrus.
We speculated that the above oxidative stress-related events should be accomplished at STZ3w in the brains of STZ-induced
diabetes animal models. Therefore, the aim of the present study was to investigate chronological changes in SOD1 immunoreactivity
associated with lipid peroxidation and inflammatory responses in the hippocampi of STZ-induced type I diabetic rats. 相似文献