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991.
Nan Zhang Zhen Song Yuhua Xie Ping Cui Hongxia Jiang Tao Yang Ruicheng Ju Yuhua Zhao Jinyu Li Xunli Liu 《World journal of microbiology & biotechnology》2013,29(8):1443-1452
An antifungal Actinomyces BS-112 strain, with Aspergillus flavus as the target pathogen, was isolated from soil in the forest land of Mountain Tai. This strain showed a strong antagonistic activity against various mold fungi in food and feed. Strain BS-112 was identified as Streptomyces hygroscopicus based on its morphologic, cultural, physiological, biochemical characteristics, cell wall components and 16S rDNA sequence. Four active components were separated and purified from strain BS-112. These four antifungal components were identified as tetrins A and B and tetramycins A and B using spectroscopic analysis including mass spectrometry and nuclear magnetic resonance spectroscopy. Tetrins A and B and tetramycins A and B strongly inhibited the growth of A. flavus, A. alutaceus, A. niger, and A. fumigatus in vitro. 相似文献
992.
兼性甲烷氧化菌在新陈代谢上具有独一无二的特性:它们能够利用甲烷或一些含碳碳键的有机物作为唯一碳源和能源.甲基细胞菌属(Methylocella)、甲基孢囊菌属(Methylocystis)和甲基帽菌属(Methylocapsa)的一些菌株已经被确定为兼性甲烷氧化菌.它们都属于a-变形菌纲,能够像利用甲烷一样在大分子有机酸或乙醇里生长.本文全面系统地总结了兼性甲烷氧化菌的研究发展历史,推断出兼性甲烷氧化菌易在酸性环境富集生长;介绍了与之有相近功能的兼性甲烷氧化生物;浅析了其对多碳化合物的代谢机理;最后讨论了兼性甲烷氧化菌研究的现存问题和工程应用前景. 相似文献
993.
994.
Haipo Xu Yupeng Sun Xiaolong Zhang Ronghua Chen Zhixiong Cai Bixing Zhao Xiaolong Liu Jingfeng Liu 《Microbial biotechnology》2023,16(4):838-846
Currently, malaria is still one of the major public health problems commonly caused by the four Plasmodium species. The similar symptoms of malaria and the COVID-19 epidemic of fever or fatigue lead to frequent misdiagnosis. The disadvantages of existing detection methods, such as time-consuming, costly, complicated operation, need for experienced technicians, and indistinguishable typing, lead to difficulties in meeting the clinical requirements of rapid, easy, and accurate typing of common Plasmodium species. In this study, we developed and optimized a universal two-dimensional labelled probe-mediated melting curve analysis (UP-MCA) assay based on multiplex and asymmetric PCR for rapid and accurate typing of five Plasmodium species, including novel human Plasmodium, Plasmodium knowlesi (Pk), in a single closed tube following genome extraction. The assay showed a limit of detection (LOD) of 10 copies per reaction and could accurately distinguish Plasmodium species from intra-plasmodium and other pathogens. Additionally, we proposed and validated different methods of fluorescence quenching and tag design for probes that are suitable for UP-MCA assays. Moreover, the clinical performance of the Plasmodium UP-MCA assay using a base-quenched universal probe was evaluated using 226 samples and showed a sensitivity of 100% (164/164) and specificity of 100% (62/62) at a 99% confidence interval, with the microscopy method as the gold standard. In summary, the UP-MCA assay showed excellent sensitivity, specificity, and accuracy for genotyping Plasmodium species spp. Additionally, it facilitates convenient and rapid Plasmodium detection in routine clinical practice and has great potential for clinical translation. 相似文献
995.
Chunqiao Zhao Yuesen Yue Qiang Guo Juying Wu Jinku Song Qinghai Wang Cui Li Yang Hu Sisi Wang Ning Yuan Zhengang Wang Ranran Fan Xincun Hou Xifeng Fan 《Global Change Biology Bioenergy》2023,15(9):1105-1118
Miscanthus spp. show excellent application prospects due to its bioenergy potential and multiple ecological services. Annual N export with biomass harvest from Miscanthus, even without fertilizer supplement, do not reduce soil N levels. The question arises regarding how Miscanthus can maintain stable soil N levels. Metagenomic strategies were used to reveal soil N-cycling-related microbiome and their functional contributions to processes of soil N-cycling based on the comparison among the bare land, cropland, 10-year Miscanthus × giganteus, and 15-year Miscanthus sacchariflorus fields. The results showed that, after long-term cropland-to-Miscanthus conversion (LCMC), 16 of 21 bacterial phyla and all the archaeal phyla exhibited significant changes. Soil microbial denitrification and nitrification functions were significantly weakened, and N fixation (NF) was significantly enhanced. The biosynthesis of amino acids, especially alanine, aspartate, and glutamate metabolism, in soil N-cycling-related microbiome was dramatically promoted. The genus Anaeromyxobacter contributed largely to the NF process after LCMC. Variations in the soil available potassium, available N, organic C, and total N contents drove a functional shift of soil microbiome from cropland to Miscanthus pattern. We conclude that Miscanthus can recruit Anaeromyxobacter communities to enhance NF benefiting its biomass sustainability and soil N balance. 相似文献
996.
Yanhui Liu Guohui Zhang Yulong Guan Xiaoliang Zhao Quan Wang Hua Li Jinhong Qi 《Journal of cellular and molecular medicine》2020,24(18):10615-10620
The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population. 相似文献
997.
998.
999.
Guoli Zhao Yingga Wu Li Du Wenhua Li Ying Xiong Aiyu Yao Qifu Wang Yong Q. Zhang 《PLoS genetics》2015,11(3)
Synaptic connections must be precisely controlled to ensure proper neural circuit formation. In Drosophila melanogaster, bone morphogenetic protein (BMP) promotes growth of the neuromuscular junction (NMJ) by binding and activating the BMP ligand receptors wishful thinking (Wit) and thickveins (Tkv) expressed in motor neurons. We report here that an evolutionally conserved, previously uncharacterized member of the S6 kinase (S6K) family S6K like (S6KL) acts as a negative regulator of BMP signaling. S6KL null mutants were viable and fertile but exhibited more satellite boutons, fewer and larger synaptic vesicles, larger spontaneous miniature excitatory junctional potential (mEJP) amplitudes, and reduced synaptic endocytosis at the NMJ terminals. Reducing the gene dose by half of tkv in S6KL mutant background reversed the NMJ overgrowth phenotype. The NMJ phenotypes of S6KL mutants were accompanied by an elevated level of Tkv protein and phosphorylated Mad, an effector of the BMP signaling pathway, in the nervous system. In addition, Tkv physically interacted with S6KL in cultured S2 cells. Furthermore, knockdown of S6KL enhanced Tkv expression, while S6KL overexpression downregulated Tkv in cultured S2 cells. This latter effect was blocked by the proteasome inhibitor MG132. Our results together demonstrate for the first time that S6KL regulates synaptic development and function by facilitating proteasomal degradation of the BMP receptor Tkv. 相似文献
1000.
Qiang Tong Qing Cai Tristan de Mooij Xia Xu Shengming Dai Wenchun Qu Dongbao Zhao 《PloS one》2015,10(3)