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961.
Zhang Zhe Fan Junxia Long Chuannan He Bin Hu Zhihong Jiang Chunmiao Li Yongkai Ma Long Wen Jingshang Zou Xiaojin Chen Yuan Ge Zhenxiang Zeng Bin 《Journal of industrial microbiology & biotechnology》2019,46(12):1769-1780
Journal of Industrial Microbiology & Biotechnology - The ZRT, IRT-like protein (ZIP) family exists in many species and plays an important role in many biological processes, but little is known... 相似文献
962.
Li Yanjun Yan Fangqing Wu Heyun Li Guoliang Han Yakun Ma Qian Fan Xiaoguang Zhang Chenglin Xu Qingyang Xie Xixian Chen Ning 《Journal of industrial microbiology & biotechnology》2019,46(1):81-90
Journal of Industrial Microbiology & Biotechnology - Although CRISPR/Cas9-mediated gene editing technology has developed vastly in Escherichia coli, the chromosomal integration of large DNA... 相似文献
963.
Haifeng Zhou Xiaolun He Shuo Wang Qingzhou Ma Bingjian Sun Shengli Ding Linlin Chen Meng Zhang Honglian Li 《Environmental microbiology》2019,21(8):2740-2754
To investigate the distribution and diversity of the pathogens associated with Fusarium crown rot in the Huanghuai wheat-growing region (HHWGR) of China, we collected wheat samples with symptomatic stem bases from seven provinces in the HHWGR between 2013 and 2016. A total of 1196 isolates obtained from 222 locations were identified as 9 Fusarium species based on morphological and molecular identification. Of these pathogen species, F. pseudograminearum was the dominant species. Furthermore, F. sinensis was isolated from the disease specimens and tested for virulence to wheat. The result of the pathogenicity revealed that an intraspecific differentiation existed in F. pseudograminearum; sequence analysis of the EF-1α gene showed that 194 F. pseudograminearum isolates were differentiated into two distinct clades which closed to the strains from Australia and China respectively, but neither pathogenicity nor EF-1α sequence was related to the geographic origins of these isolates. However, universal rice primers-polymerase chain reaction showed a correlation with the geographical origins of the 194 isolates, which were divided into eight subclusters, the level of genetic diversity was higher within a geographical population than among the different populations. The results of these analyses can be directly used to facilitate disease monitoring and development of control strategies. 相似文献
964.
Yonghong Yu Jianrong Ma Qiaoqiao Guo Jincheng Ma Haihong Wang 《Molecular Plant Pathology》2019,20(12):1696-1709
Xanthomonas campestris pv. campestris (Xcc), the causal agent of black rot in crucifers, produces a membrane-bound yellow pigment called xanthomonadin to protect against photobiological and peroxidative damage, and uses a quorum-sensing mechanism mediated by the diffusible signal factor (DSF) family signals to regulate virulence factors production. The Xcc gene XCC4003, annotated as Xcc fabG3, is located in the pig cluster, which may be responsible for xanthomonadin synthesis. We report that fabG3 expression restored the growth of the Escherichia coli fabG temperature-sensitive mutant CL104 under non-permissive conditions. In vitro assays demonstrated that FabG3 catalyses the reduction of 3-oxoacyl-acyl carrier protein (ACP) intermediates in fatty acid synthetic reactions, although FabG3 had a lower activity than FabG1. Moreover, the fabG3 deletion did not affect growth or fatty acid composition. These results indicate that Xcc fabG3 encodes a 3-oxoacyl-ACP reductase, but is not essential for growth or fatty acid synthesis. However, the Xcc fabG3 knock-out mutant abolished xanthomonadin production, which could be only restored by wild-type fabG3, but not by other 3-oxoacyl-ACP reductase-encoding genes, indicating that Xcc FabG3 is specifically involved in xanthomonadin biosynthesis. Additionally, our study also shows that the Xcc fabG3-disrupted mutant affects Xcc virulence in host plants. 相似文献
965.
中国自然保护地空间重叠分析与保护地体系优化整合对策 总被引:5,自引:0,他引:5
自然保护地体系的构建是国际社会高度重视的生物多样性保护策略。近年来, 中国已关注到自然保护地空间重叠交叉的问题, 并出台了《关于建立以国家公园为主体的自然保护地体系的指导意见》。为落实这一战略, 需要对现有保护地的彼此关系与空间分布进行系统研究。为此, 本研究收集了8,572个不同类型和级别自然保护地的坐标、生态系统类型、行政区域及边界等信息, 筛选出1,532个具有空间重叠、管理部门交叉的自然保护地, 计算地理集中指数并采用ArcGIS软件进行了核密度分析, 得出空间重叠保护地分布的生态地理区、生态系统类型、交叉管理部门、所在省份等空间分布特点。研究结果显示: (1)鲁中山区、太行山、大别山、天目山-怀玉山、皖江等生态功能区的自然保护地重叠最为严重(核密度Mean > 6, Max > 8), 其中太行山区、大别山区、天目山-怀玉山区为重叠保护地密度高的生物多样性优先保护区, 目前10个国家公园试点区域中仅大熊猫国家公园体制试点区、湖南南山国家公园体制试点区、钱江源国家公园体制试点区三处位于保护地重叠高密度区; (2)原主管部门中, 原国家林业局与住房和城乡建设部的交叉管理保护地数量最多, 为294个; (3)黑龙江、安徽、山东、河南、湖北、湖南等省范围内的自然保护地空间重叠状况明显高于其他省区, 而晋冀豫与皖鄂赣这两处三省交界处重叠程度更高, 其他多处三省交界区域也存在保护地的中度重叠。故上述生态地理区、原主管部门与行政区应作为中国自然保护地体系优先普查区域与优化整合重点对象。基于重叠保护地核密度热点区、生物多样性保护优先区与生态系统文化服务的分析框架, 本研究按照国家公园、自然保护区、自然公园三类, 对不同生态功能区自然保护地优化整合优先性与类型提出了初步建议, 以期为当前中国自然保护地体系改革的紧迫需求提供参考。 相似文献
966.
967.
968.
Teng Liu Min Lu Binguo Chen Qinsong Zhong Jingyu Li Honghui He Hua Mao Hui Ma 《Journal of biophotonics》2019,12(12)
Recently, the incidence of inflammatory bowel diseases, especially the Crohn's disease (CD) and gastrointestinal luminal tuberculosis (ITB), has grown rapidly worldwide. Currently there is no general gold standard to distinguish between CD and ITB tissues, which both have tuberculosis and surrounding fibrous structures. Mueller matrix imaging technique is suitable for describing the location, density and distribution behavior of such fibrous structures. In this study, we apply the Mueller matrix microscopic imaging to the CD and ITB tissue samples. The 2D Mueller matrix images of the CD and ITB tissue slices are measured using the Mueller matrix microscope developed in our previous study, then the Mueller matrix polar decomposition and Mueller matrix transformation parameters are calculated. To evaluate the distribution features of the fibrous structures surrounding the tuberculosis areas more quantitatively and precisely, we analyze the retardance related Mueller matrix derived parameters, which show clear different distribution behaviors between the CD and ITB tissues, using the Tamura image processing method. It is demonstrated that the Mueller matrix derived parameters can reveal the structural features of tuberculosis areas and be used as quantitative indicators to distinguish between CD and ITB tissues, which may be useful for the clinical diagnosis. 相似文献
969.
Yao Yu Menghan Yu Jian Liu Ning Ding Jiangmei Huang Dong Wan Yuliang Zhao Zhenhe Ma 《Journal of biophotonics》2019,12(11)
The objective of this study is to establish a novel method for continuously monitoring thrombus progression with various outcome measures and to assess the efficacy of antithrombotic drugs in murine thrombosis model in mice. In the study, thrombus was induced in the femoral vein of mice by FeCl3 and monitored over time by spectral‐domain optical coherence tomography (OCT). Three‐dimensional images of thrombi with or without heparin as an antithrombotic agent were obtained from OCT angiography. In addition, several parameters of thrombi were analyzed and compared between control and anticoagulant groups. By using OCT, we were able to trace thrombus generation in the same mouse in real time. We found that in our model heparin reduced thrombus size by ~60% and thrombus cross‐sectional area by 50%. OCT results also show that both time to thrombus size (>0.02mm3) and time to occlusion (>30%) were significantly reduced after heparin addition. This study demonstrates that OCT reliably monitors thrombus generation and progression from various aspects including thrombus size. This enables us to measure the kinetic of thrombosis more accurately, and effectively evaluate the efficacy and activities of antithrombotic drugs. This model may represent a useful tool in antithrombotic drug discoveries in preclinical studies. 相似文献
970.
Various tissue optical clearing techniques have sprung up for large volume imaging. However, there are few methods showed clearing and imaging data on different organs while most of them were focused on mouse brain, and as a result, it is difficult to select the suitable method for organs in practical applications due to lack of quantitative evaluation and comprehensive comparison. Therefore, it is necessary to evaluate and compare the performances of clearing methods for different organs. In this paper, several typical optical clearing methods were applied, including 3DISCO, uDISCO, SeeDB, FRUIT, CUBIC, ScaleS and PACT to clear intact brain, heart, kidney, liver, spleen, stomach, lung, small intestine, skin and muscle. The clearing efficiency, sample deformation, fluorescence preservation and imaging depth of these methods were quantitatively evaluated. Finally, based on the systemic evaluation of various parameters described above, the appropriate clearing method for specific organ including kidney or intestine was screened out. This paper will provide important references for selection of appropriate clearing methods in related researches. 相似文献