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131.
Wei Zhao Xiao-Hua Wang Hong-Mei Li Shi-Hua Wang Tao Chen Zhan-Peng Yuan Ya-Jie Tang 《Applied microbiology and biotechnology》2014,98(5):1991-2002
Fifty-two polysaccharides were isolated from the fermentation systems of Tuber melanosporum, Tuber indicum, Tuber sinense, Tuber aestivum and the fruiting bodies of Tuber indicum, Tuber himalayense, Tuber sinense by elution with an activated carbon column. Polysaccharides from Tuber fermentation system exhibited relatively higher in vitro antitumor activity against HepG2, A549, HCT-116, SK-BR-3, and HL-60 cells than those from Tuber fruiting bodies. All polysaccharides were mainly composed of d-mannose, d-glucose, and d-galactose, which suggested that the polysaccharides from Tuber fruiting bodies and fermentation system have identical chemical compositions. The results of antitumor activity and structural identification indicated that the polysaccharide fractions could promote antitumor activity. Tuber polysaccharides from Tuber fermentation system exhibited relatively higher than that from Tuber fruiting bodies. These results confirm the potential of Tuber fermentation mycelia for use as an alternative resource for its fruiting bodies. 相似文献
132.
The net photosynthetic rate (P N), the sample room CO2 concentration (CO2S) and the intercellular CO2 concentration (C i) in response to PAR, of C3 (wheat and bean) and C4 (maize and three-colored amaranth) plants were measured. Results showed that photorespiration (R p) of wheat and bean could not occur at 2 % O2. At 2 % O2 and 0 μmol mol?1 CO2, P N can be used to estimate the rate of mitochondrial respiration in the light (R d). The R d decreased with increasing PAR, and ranged between 3.20 and 2.09 μmol CO2 m?2 s?1 in wheat. The trend was similar for bean (between 2.95 and 1.70 μmol CO2 m?2 s?1), maize (between 2.27 and 0.62 μmol CO2 m?2 s?1) and three-colored amaranth (between 1.37 and 0.49 μmol CO2 m?2 s?1). The widely observed phenomenon of R d being lower than R n can be attributed to refixation, rather than light inhibition. For all plants tested, CO2 recovery rates increased with increasing light intensity from 32 to 55 % (wheat), 29 to 59 % (bean), 54 to 87 % (maize) and 72 to 90 % (three-colored amaranth) at 50 and 2,000 μmol m?2 s?1, respectively. 相似文献
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Presently, the understanding of bacterial enteric diseases in the community and their virulence factors relies almost exclusively on clinical disease reporting and examination of clinical pathogen isolates. This study aimed to investigate the feasibility of an alternative approach that monitors potential enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) prevalence and intimin gene (eae) diversity in a community by directly quantifying and characterizing target virulence genes in the sanitary sewage. The quantitative PCR (qPCR) quantification of the eae, stx1, and stx2 genes in sanitary sewage samples collected over a 13-month period detected eae in all 13 monthly sewage samples at significantly higher abundance (93 to 7,240 calibrator cell equivalents [CCE]/100 ml) than stx1 and stx2, which were detected sporadically. The prevalence level of potential EPEC in the sanitary sewage was estimated by calculating the ratio of eae to uidA, which averaged 1.0% (σ = 0.4%) over the 13-month period. Cloning and sequencing of the eae gene directly from the sewage samples covered the majority of the eae diversity in the sewage and detected 17 unique eae alleles belonging to 14 subtypes. Among them, eae-β2 was identified to be the most prevalent subtype in the sewage, with the highest detection frequency in the clone libraries (41.2%) and within the different sampling months (85.7%). Additionally, sewage and environmental E. coli isolates were also obtained and used to determine the detection frequencies of the virulence genes as well as eae genetic diversity for comparison. 相似文献
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138.
Kunda P Rodrigues NT Moeendarbary E Liu T Ivetic A Charras G Baum B 《Current biology : CB》2012,22(3):231-236
Animal cells undergo dramatic actin-dependent changes in shape as they progress through mitosis; they round up upon mitotic entry and elongate during chromosome segregation before dividing into two [1-3]. Moesin, the sole Drosophila ERM-family protein [4], plays a critical role in this process, through the construction of a stiff, rounded metaphase cortex [5-7]. At mitotic exit, this rigid cortex must be dismantled to allow for anaphase elongation and cytokinesis through the loss of the active pool of phospho-Thr559moesin from cell poles. Here, in an RNA interference (RNAi) screen for phosphatases involved in the temporal and spatial control of moesin, we identify PP1-87B RNAi as having elevated p-moesin levels and reduced cortical compliance. In mitosis, RNAi-induced depletion of PP1-87B or depletion of a conserved noncatalytic PP1 phosphatase subunit Sds22 leads to defects in p-moesin clearance from cell poles at anaphase, a delay in anaphase elongation, together with defects in bipolar anaphase relaxation and cytokinesis. Importantly, similar cortical defects are seen at anaphase following the expression of a constitutively active, phosphomimetic version of moesin. These data reveal a new role for the PP1-87B/Sds22 phosphatase, an important regulator of the metaphase-anaphase transition, in coupling moesin-dependent cell shape changes to mitotic exit. 相似文献
139.
The full-length genome analysis of a street rabies virus strain isolated in Yunnan province of China
Jian Zhang Hai-lin Zhang Xiao-yan Tao Hao Li Qing Tang Xiu-yun Jiang Guo-dong Liang 《中国病毒学》2012,27(3):204-213
The epidemic of rabies has rapidly increased and expanded in Yunnan province in recent years.In order to further analyze and understand the etiological reasons for the rapid expansion of rabies in Yunn... 相似文献
140.
The pH-modified citrus pectin (MCP) has been demonstrated to inhibit galectin-3 in cancer progression. The components and structures of MCP related to this inhibition remained unknown. In this paper, we fractionated MCP on DEAE-cellulose column into a homogenous neutral fraction MCP-N (about 20?kDa) and a pectin mixture fraction MCP-A (wide molecular distribution on Sepharose CL-6B chromatography). Both MCP-N and MCP-A inhibited hemagglutination mediated by galectin-3 with minimum inhibition concentration (MIC) 625 and 0.5?μg/ml, respectively. MCP-N was identified to be a type I arabinogalactan (AG-I) with a main chain of β-1→4-galactan. MCP-N was digested by α-L-arabinofuranosidase to give its main chain structure fraction (M-galactan, around 18?kDa), which was more active than the original molecule, MIC 50?μg/ml. The acidic degradation of M-galactan increased the inhibitory activity, MIC about 5 times lower than M-galactan. These results above showed that the functional motif of the β-1→4-galactan fragment might lie in the terminal residues rather than in the internal region of the chain. Therefore, MCP-N and its degraded products might be developed to new potential galectin-3 inhibitors. This is the first report concerning the fractionation of MCP and its components on galectin-3 inhibition. The information provided in this paper is valuable for screening more active galectin-3 inhibitors from natural polysaccharides. 相似文献