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The paper reports the isolation and structural elucidation of seven diketopiperazines from the title microorganisms. Although all isolates are known, three of which were isolated from the actinomycetes for the first time. And this is also the first report to isolate four DKPs from the D. avara-associated microorganism. 相似文献
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Xiaohui Liang Xiangyi Fang Manwen Yao Yucong Yang Junfeng Li Hongjun Liu Linyu Wang 《Luminescence》2016,31(1):168-172
Direct competitive chemiluminescence immunoassays (CLIA) based on gold‐coated magnetic nanospheres (Au‐MNPs) were developed for rapid analysis of chloramphenicol (CAP). The Au‐MNPs were modified with carboxyl groups and amino groups by 11‐mercaptoundecanoic acid (MUA) and cysteamine respectively, and then were respectively conjugated with CAP base and CAP succinate via an activating reaction using 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N‐hydroxysuccinimide (NHS). NSP‐DMAE‐NHS, a new and effective luminescence reagent, was employed to label anti‐CAP antibody (mAb) as a tracer in direct CLIA for CAP detection using a ‘homemade’ luminescent measurement system that was set up with a photomultiplier tube (PMT) and a photon counting unit linked to a computer. The sensitivities and limits of detection (LODs) of the two methods were obtained and compared according to the inhibition curves. The 50% inhibition concentration (IC50) values of the two methods were about 0.044 ng/mL and 0.072 ng/mL respectively and LODs were approximately 0.001 ng/mL and 0.006 ng/mL respectively. To our knowledge, they were much more sensitive than any traditional enzyme‐linked immunosorbent assay (ELISA) ever reported. Moreover, the new luminescence reagent NSP‐DMAE‐NHS is much more sensitive and stable than luminol and its derivatives, contributing to the sensitivity enhancement. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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中华按蚊CYP6Y亚家族基因的鉴定和生物信息学分析 总被引:1,自引:0,他引:1
【目的】鉴定中华按蚊Anopheles sinensis CYP6Y亚家族基因,分析它们的结构和特征,推测其可能的功能。【方法】以冈比亚按蚊An. gambiae CYP6Y1作为询问序列,通过双向Blast方法检索中华按蚊转录组中CYP6Y亚家族基因,并通过生物信息学方法分析基因结构、特征及可能的功能。【结果】从中华按蚊转录组测序数据中鉴定出2条CYP6Y亚家族基因,分别命名为AsCYP6Y1(GenBank登录号:KF709397)和AsCYP6Y2(GenBank登录号:KF709398)。序列分析显示,AsCYP6Y1和AsCYP6Y2全长分别为1 713 bp和1 815 bp,分别编码502和526个氨基酸。基因结构分析显示,该亚家族基因仅含有1个相位1型内含子并与其他P450基因形成保守的共线性分布。蛋白结构分析显示,这2个基因编码的蛋白含P450特有的5个特征序列和6个底物结合位点,且均不存在信号肽,其亚细胞定位为细胞质。3D结构分析显示,AsCYP6Y1有18条α螺旋和13股反向平行的β折叠,AsCYP6Y2有19条α螺旋和11股反向平行的β折叠。通过同样的方法,在达林按蚊An. darlingi中也鉴定出2个CYP6Y亚家族基因。系统进化分析显示,AsCYP6Y1和AsCYP6Y2分别与其他3种按蚊的CYP6Y1和CYP6Y2聚成一支,Bootstrap值均大于90%。替换率分析显示,中华按蚊AsCYP6Y1和AsCYP6Y2与其他3种按蚊同源基因的Ka/Ks均小于1。相对进化速率分析显示,中华按蚊CYP6Y和CYP6M亚家族的相对进化速率均显著快于CYP6P亚家族,而CYP6Y和CYP6M亚家族之间没有显著差异。【结论】在中华按蚊和达林按蚊中存在2个CYP6Y亚家族基因,之前在冈比亚按蚊和不吉按蚊An. funestus中也发现2个CYP6Y亚家族基因,表明CYP6Y亚家族基因可能在按蚊属广泛存在,且可能为按蚊属昆虫所特有。 相似文献
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记述采自河南省蚱科二新种,即鸡公山蚱Tetrix jigongshanensis sp. nov.和突背蚱Tetrix glochinota sp. nov..鸡公山蚱近似于凹额蚱Tetrix cavifrontalis Liang, 1998, 主要区别为:1)头顶前缘平直;2)侧面观,头顶与额面隆起呈钝角形;3)侧面观,额面隆在侧单眼前直,不凹陷;4)侧观,前胸背板上缘呈弧形;5)前胸背板前缘钝角形突出;6)后突到达后足股节中部;7)后翅略不到达后突顶端;8)中足股节明显宽于前翅宽.突背蚱近似于仿蚱Tetrix simulans(B.-Bienko, 1929)及云龙蚱Tetrix yunlongensis Zheng et Mao, 2002, 其与二者的区别为:1)头顶前缘平直;2)侧面观,背板上缘前半部球形突出,后半段平直;3)后突到达后足股节顶端.其区别于前者为:1)侧面观,额面隆起在侧单眼前凹陷;2)中足股节宽于前翅等宽.其区别于后者为头顶宽为一眼宽的1.7倍.模式标本保存于陕西师范大学动物研究所昆虫标本室. 相似文献
109.
Jing Guo Tomer Fishman Yao Wang Alessio Miatto Wendy Wuyts Licheng Zheng Heming Wang Hiroki Tanikawa 《Journal of Industrial Ecology》2021,25(1):162-175
Construction materials are considerable forces of global environmental impacts, but their dynamics vis‐à‐vis urban development are poorly documented, in part because their long lifespans require elusive and sometimes nonexistent decade‐long high‐resolution data. This study analyzes the construction material flow and stock trends that shaped and were shaped by the development, decline, and renewal of the Tiexi district of Shenyang, a microcosm of China's urban transformations since the early 20th century. Chronicling building‐by‐building the material flows and stock accumulations involved in the buildup of this area, we shed light on the physical resource context of its socioeconomic history. We find that 42 million tonnes of construction materials were needed to develop the Tiexi district from 1910 to 2018, and 18 million tonnes of material outflows were generated by end‐of‐life building demolition. However, over 55% of inflows and 93% of outflows occurred since 2002 during a complete redevelopment of the district. Only small portions of end‐of‐life materials could have been reused or recycled because of temporal and typological mismatches of supply and demand and technical limitations. Our analysis reveals a dramatic decrease in median building lifetimes to as low as 6 years in the early 21st century. These findings contribute to the discussion of long‐term environmental efficiency and sustainability of societal development through construction and reflect on the challenges of urban renewal processes not only in China but also in other developing and developed countries that lost (or may lose) their traditional economic base and restructure their urban forms. This article met the requirements for a Silver/Silver JIE data openness badge described at http://jie.click/badges . 相似文献
110.
通过野外观察、室内饲养等方法研究了酢浆灰蝶Pseudozizeeria maha(Kollar)的生活史及生物学特性。在南京地区,该蝶幼虫以酢浆草科Oxalidaceae的黄花酢浆草(Oxalis corniculataL.)为食,1年5代,世代交替发生。酢浆灰蝶在10月末以蛹在枯枝落叶或土壤表层浅洞中越冬,越冬代成虫次年5月始见、中旬为高峰期,5月中旬始见第1代卵及幼虫,6—10月间各月各虫态均同时发生,期间每月中下旬为成虫活动高峰期。幼虫共4龄,野外2~4龄幼虫具迁移、避热与适蚁行为。在室内饲养条件下,卵期为3~4d,幼虫期为22~26d,蛹期为6~7d。 相似文献