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991.
Gunsup Lee Hye-Kyung Shim Myung-Hee Kwon Su-Hwan Son Ki-Yoon Kim Eul-Yong Park Taek-Kyun Lee Woo-Ram Lee Chung-Kyoon Auh Donggiun Kim Yong-Sung Kim Sukchan Lee 《Plant Cell, Tissue and Organ Culture》2013,115(2):179-187
A catalytic single chain variable antibody (scFv), 3D8 scFv, which has DNase activities, was functionally expressed in Nicotiana tabacum. The subcellular localization of the GFP-fused 3D8 indicated that the 3D8 protein was expressed in the cytosol of the N. tabacum protoplasts. Progenies of the transgenic tobacco plants exhibited complete resistance against two single stranded (ss) DNA geminiviruses, including the Beet curly top virus and the Beet severe curly top virus, without viral accumulation or disease symptoms. We presented a novel strategy for targeting the viral DNA itself in a sequence non-specific manner, rather than the viral proteins or RNAs, in order to generate virus-resistant transgenic plants. No noticeable adverse effects on the growth and reproduction of the transgenic plants were observed. Our results demonstrated that targeting viral DNA is an effective strategy for protecting plants from ssDNA viruses. 相似文献
992.
Reza Khakvar Kamaruzaman Sijam Kwai Lin Thong Son Radu Mui Yun Wong Jeffery Jones 《Archives Of Phytopathology And Plant Protection》2013,46(6):594-601
Abstract Surveys were conducted between the years of 2005 and 2006 at several locations in the northern, central and southern parts of West Malaysia to study the polymorphism of Ralstonia solanacearum strains. These sites included vegetables and farms with known hosts of the pathogen, such as banana, tomato, eggplant, chili and tobacco. Samples were collected from the suspected wilted plants and weeds, including soil and water samples, in selected areas. The bacterium was isolated in all samples using semi-selective tetrazolium chloride medium (TZC). The bacteria strains were detected by using the BIOLOG identification system and were confirmed by nested-PCR. Fatty Acid Methyl Esters (FAME) profiling was performed to determine polymorphism among 58 bacterial isolates. The results showed that the fatty acid composition varied for all R. solanacearum isolates. Grouping of R. solanacearum isolates by fatty acid composition suggested that the existence of distinct groups that were significantly related to host of bacteria but low correlation between fatty acid profiles and biovar or sampling site was detected. A unique FAME profile was found among the strains that have been isolated from banana. 相似文献
993.
994.
Do Bich Hang Nguyen Thi Phuong Thao Ho Nguyen Quynh Chi Le Thanh Long Hoang Nghia Son Doan Chinh Chung 《Molecular biology reports》2020,47(5):3675-3689
Molecular Biology Reports - Malignant melanoma is a very aggressive and serious type of cutaneous cancer. Previous studies indicated the anti-cancer activity of aqueous extract of Moringa oleifera... 相似文献
995.
Vo Minh Son Chin-Chyuan Chang Mi-Chen Wu Yuan-Kuang Guu Chiu-Hsia Chiu Winton Cheng 《Fish & shellfish immunology》2009,26(5):691-698
The percent weight gain (PWG) and feed efficiency (FE) of Epinephelus coioides were calculated, and the lactobacilli and total microbiota in the posterior intestines, and non-specific immune parameters of grouper, and its susceptibility to Streptococcus sp. and an iridovirus were determined when the fish were fed diets containing Lactobacillus plantarum at 0 (control), 106, 108, or 1010 colony-forming units (cfu) kg?1 for 4 weeks. Results showed that grouper fed a diet containing L. plantarum at the levels of 106, 108, and 1010 cfu kg?1 had significantly increased PGW and FE especially at 108 cfu kg?1 group which were 404.6% and 1.26, respectively. L. plantarum significantly increased in the fish posterior intestines during the L. plantarum feeding period, but decreased rapidly from the intestine within 1 week after changing to the control diet (without L. plantarum). Fish fed a diet containing L. plantarum at 106 and 108 cfu kg?1 had significantly higher survival rates than those fed the control diet after challenge with Streptococcus sp., as well as those fed 108 cfu kg?1 after challenge with an iridovirus, causing increases in the survival rates of 23.3%, 20.0%, and 36.7%, respectively, compared to the control group. The alternative complement activity (ACH50) level of fish fed diets containing L. plantarum after 4 weeks was significantly higher than that of fish fed the control diet, and that of the 108 cfu kg?1 group was significantly higher than those of the 106 and 1010 cfu kg?1 groups, which increased by 83.4% compared to the control group. The lysozyme activity and glutathione peroxidase (GPx) activity of fish fed the L. plantarum-containing diets at 108 and 1010 cfu kg?1 significantly increased compared to those fed the 106 cfu kg?1 L. plantarum diet and control diet, and had increased by 76.3% and 136.6%, and 57.1% and 113.3%, respectively, compared to those fed the control diet. The phagocytic activity (PA), phagocytic index (PI), and respiratory bursts of head kidney leucocytes of fish fed 106, 108, and 1010 cfu kg?1 L. plantarum diets were significantly higher than those of fish fed the control diet after 4 weeks of feeding, and increased 2.2-, 2.2-, and 2.3-fold; 1.8-, 1.8-, and 2.0-fold; and 1.4-, 1.4-, and 1.4-fold, respectively, compared to the control group. We therefore recommend dietary L. plantarum administration at 108 cfu kg?1 to promote growth and enhance immunity and resistance against Streptococcus sp. and an iridovirus of E. coioides. 相似文献
996.
997.
X. Nassif † J. C. Mathison E. Wolfson J. A. Koziol R. J. Ulevitch M. Son † 《Molecular microbiology》1992,6(5):591-597
Tumour necrosis factor alpha (TNF-alpha) has been shown to be the principal mediator of Gram-negative bacterial endotoxin-induced shock. Nevertheless, evidence suggests that TNF-alpha plays a beneficial role in controlling bacterial infections when multiplication of the microorganism is required to kill the host. Using an infant rat model of Neisseria meningitidis infection, we found that blood TNF-alpha concentration reaches a peak three hours after intraperitoneal injection of 3 x 10(6) bacteria. Thereafter, the level of TNF-alpha decreased and was undetectable six to eight hours after infection. A correlation was observed between the magnitude of initial TNF-alpha response and a fatal outcome. Pretreatment of the animals with polyclonal anti-TNF antiserum significantly reduced mortality relative to animals pretreated with control serum. However, pretreatment of animals with anti-TNF antibody did not alter the bacterial invasion of the cerebrospinal fluid. Injection of heat-killed bacteria did not cause death and induced lower TNF-alpha levels than the same number of live bacteria. This excludes the possibility that the role of TNF-alpha is to mediate a shock induced by the endotoxin component of the bacterial inoculum. These results indicate that TNF-alpha has a deleterious effect in this model of bacteraemia. Identification of the critical factors that determine the action of TNF-alpha during lethal bacteraemia will lead to a better understanding of these diseases and the development of appropriate therapeutic intervention. 相似文献
998.
Rapid and simple method for DNA extraction from plant and algal species suitable for PCR amplification using a chelating resin Chelex 100 总被引:1,自引:0,他引:1
Kwon HwangBo Su Hyun Son Jong Suk Lee Sung Ran Min Suk Min Ko Jang R. Liu Dongsu Choi Won Joong Jeong 《Plant biotechnology reports》2010,4(1):49-52
A DNA extraction method using Chelex 100 is widely used for bacteria, Chlamydomonas, and animal cell lines, but only rarely for plant materials due to the need for additional time-consuming and tedious steps.
We have modified the Chelex 100 protocol and successfully developed a rapid and simple method of DNA extraction for efficient
PCR-based detection of transgenes from a variety of transgenic plant and algal species. Our protocol consists of homogenizing
plant tissue with a pestle, boiling the homogenized tissue in a microfuge tube with 5% Chelex 100 for 5 min, and centrifuging
the boiled mixture. The supernatant, which is used for PCR analysis, was able to successfully amplify transgenes in transgenic
tobacco, tomato, potato, Arabidopsis, rice, strawberry, Spirodela polyrhiza, Chlamydomonas, and Porphyra tenera. The entire DNA extraction procedure requires <15 min and is therefore comparable to that used for bacteria, Chlamydomonas, and animal cell lines. 相似文献
999.
Joon Kim Dongho Lee Jinkyu Hong Sinkyu Kang Su-Jin Kim Sang-Ki Moon Jong-Hwan Lim Yowhan Son Jaeseok Lee Sanghyun Kim Namchil Woo Kyongha Kim Buyong Lee Byong-Lyol Lee Sung Kim 《Ecological Research》2006,21(6):881-889
The KoFlux program is dedicated to understanding the fluxes of energy and matter, water resource management, and net ecosystem
production in key ecosystems of Monsoon Asia. Under the framework of AsiaFlux, it is a joint effort with determined, comprehensive
international strategies to bring Asia’s key ecosystems under observation. Built upon the augmented KoFlux infrastructure
(i.e., Gwangneung supersite), the ‘HydroKorea’ and ‘CarboKorea’ projects pursue new methodologies to assess water and carbon
cycles at various temporal, spatial, and process scales. Particularly, the multiscaling approaches are used to link process-level
studies, flux footprint, ecohydrological and biogeochemical schemes, and high-resolution satellite images. We hope that the
work presented here encourages more ground-breaking studies aimed at bridging the gaps in the cross-scale studies of ecohydrological
and biogeochemical cycles in heterogeneous and complex landscapes. 相似文献
1000.
Crystal structure of the catalytic domain of human MAP kinase phosphatase 5: structural insight into constitutively active phosphatase 总被引:1,自引:0,他引:1
Jeong DG Yoon TS Kim JH Shim MY Jung SK Son JH Ryu SE Kim SJ 《Journal of molecular biology》2006,360(5):946-955
MAP kinase phosphatase 5 (MKP5) is a member of the mitogen-activated protein kinase phosphatase (MKP) family and selectively dephosphorylates JNK and p38. We have determined the crystal structure of the catalytic domain of human MKP5 (MKP5-C) to 1.6 A. In previously reported MKP-C structures, the residues that constitute the active site are seriously deviated from the active conformation of protein tyrosine phosphatases (PTPs), which are accompanied by low catalytic activity. High activities of MKPs are achieved by binding their cognate substrates, representing substrate-induced activation. However, the MKP5-C structure adopts an active conformation of PTP even in the absence of its substrate binding, which is consistent with the previous results that MKP5 solely possesses the intrinsic activity. Further, we identify a sequence motif common to the members of MKPs having low catalytic activity by comparing structures and sequences of other MKPs. Our structural information provides an explanation of constitutive activity of MKP5 as well as the structural insight into substrate-induced activation occurred in other MKPs. 相似文献