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51.
The iron-reducing capability of anammox bacteria was examined in this study using Percoll purified anammox bacteria. Anammox bacteria could reduce Fe(III) to Fe(II) with organic matters as the electron donor. The activity of anammox iron-reducing process was dependent on different electron donor, acceptor and pH. The highest iron-reducing activity of anammox bacteria was achieved with Fe(III)-NTA (nitrilotriacetic acid) as electron acceptor and formate as the electron donor at pH7. Similar to other iron reducers, 80 % of the iron reductase in anammox bacteria was located in the membrane fraction. Due to the chemical oxidant of NO2 ? and the NO3 ? dependent ferrous iron oxidation by anammox bacteria, the iron-reducing activity of anammox bacteria could be severely inhibited when iron-reducing pathway and the anammox process were coupled. However, the total nitrogen removal efficiency was not significantly affected in the presence of Fe(III). The iron-reducing capability of anammox bacteria could influence both N and Fe cycle on earth, and it is a potential way for wastewater treatment. 相似文献
52.
黄河三角洲刺槐白蜡混交对土壤细菌群落结构及多样性的影响 总被引:1,自引:0,他引:1
为探讨黄河三角洲刺槐白蜡混交对土壤细菌群落结构及多样性的影响,通过高通量测序技术分析比较了刺槐白蜡混交林及刺槐纯林、白蜡纯林土壤细菌群落结构及多样性。结果表明:(1)混交林与两种纯林土壤细菌群落共36门。酸杆菌门、变形菌门、放线菌门(相对丰度大于10%)为刺槐白蜡混交林与两种纯林土壤中共有的优势菌群;硝化螺旋菌门为刺槐纯林土壤中的优势菌群。不同人工林土壤中各门细菌相对丰度差异显著。(2)混交改变了土壤细菌群落结构,提高了细菌多样性。刺槐白蜡混交林土壤细菌物种数、Chao1指数、Shannon指数分别为1934.5、2629.1、9.1,显著高于两种纯林。(3)相关性分析表明,土壤含水量与放线菌门细菌呈显著正相关;pH与芽单胞菌门细菌呈极显著正相关,与酸杆菌门细菌呈显著负相关。细菌多样性与土壤含水量呈显著正相关,与速效钾、有机质含量呈显著负相关。研究表明,刺槐白蜡混交林土壤细菌群落结构与两种纯林之间有一定差异,多样性差异显著,刺槐白蜡混交改变细菌群落结构,提高细菌多样性。 相似文献
53.
基于PAE编码系统构建的半自然条件下长江江豚行为谱 总被引:2,自引:0,他引:2
识别和编制动物行为谱是深入研究动物行为及其与环境复杂关系的基础和前提。本研究于2013年8月至2014年4月以栖息在铜陵淡水豚国家级自然保护区半自然水域的8头长江江豚为研究对象,采用焦点动物取样法和随机动物取样法观察记录了动物行为发生的过程、内容和环境,并以"姿势—动作—环境"(posture-act-environment,PAE)为轴心,以行为的功能为依据,构建了长江江豚的PAE行为谱。共分辨记录了半自然水域长江江豚的8种姿势、33种动作和46种行为,并定性描述了不同行为出现频率与年龄组、性别的关系。该行为谱综合了姿势和环境信息,有助于进一步研究长江江豚的生态与行为、促进长江江豚的保护。 相似文献
54.
55.
Shuang Geng Xin-Chi Pan Ran Mei Ya-Nan Wang Ji-Quan Sun Xue-Ying Liu Yue-Qin Tang Xiao-Lei Wu 《Current microbiology》2015,70(1):110-118
A Gram staining negative, rod-shaped, aerobic bacterial strain J5-3T with a single polar flagellum was isolated from coking wastewater collected from Shaoguan, Guangdong, China. It was motile and capable of optimal growth at pH 6–8, 30 °C, and 0–2 % (w/v) NaCl. Its predominant fatty acids were 11-methyl C18:1 ω7c (29.2 %), C16:0 (20.6 %), C19:0 cyclo ω8c (18.2 %), C18:0 (11.0 %), and C18:1 ω7c/C18:1 ω6c (10.9 %) when grown on trypticase soy agar. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unknown glycolipids (GL1, GL2), and two unknown phospholipid (PL1, PL2). The predominant ubiquinone was Q-10, and the genome DNA G+C content was 61.7 mol %. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain J5-3T belonged to the family Hyphomicrobiaceae in Alphaproteobacteria. It shared the 16S rRNA gene sequence similarities of 93.8–96.1 % with the genus Devosia, 94.5–94.8 % with the genus Pelagibacterium, and <92.0 % with all the other type strains in family Hyphomicrobiaceae. It can be distinguished from the closest phylogenetic neighbors based on several phenotypic and genotypic features, including α-galactosidase activity, tetracycline susceptibility, major fatty acid composition, polar lipid profile, DNA gyrase B subunit (gyrB) gene sequence, and random-amplified polymorphic DNA profile. Therefore, we consider strain J5-3T to represent a novel species of a novel genus within the family Hyphomicrobiaceae, for which the name Paradevosia shaoguanensis gen. nov., sp. nov. is proposed. The type strain of Paradevosia shaoguanensis is J5-3T (=CGMCC 1.12430T =LMG 27409T). 相似文献
56.
Changkun Huang Huanghao Deng Yinhuai Wang Hongyi Jiang Ran Xu Xuan Zhu Zhichao Huang Xiaokun Zhao 《Journal of cellular and molecular medicine》2019,23(9):6112-6119
In recent years, circular RNAs (circRNAs) have been identified to be essential regulators of various human cancers. However, knowledge of the functions of circRNAs in prostate cancer remains very limited. The correlation between circABCC4 and human cancer is largely unknown. This study aims to investigate the biological functions of circABCC4 in prostate cancer progression and illustrate the underlying mechanism. We found that circABCC4 was remarkably up‐regulated in prostate cancer tissues and cell lines and promoted FOXP4 expression by sponging miR‐1182 in prostate cancer cells. CircABCC4 knockdown markedly suppressed prostate cancer cell proliferation, cell‐cycle progression, migration and invasion in vitro. Furthermore, silencing of the circRNA also delayed tumor growth in vivo. Taken together, our findings indicated that circABCC4 facilitates the malignant behaviour of prostate cancer by promoting FOXP4 expression through sponging of miR‐1182. The circABCC4–miR‐1182‐FOXP4 regulatory loop may be a promising therapeutic target for prostate cancer intervention. 相似文献
57.
本文通过红外线照相的方法,对发育期的林睡鼠幼鼠进行室内活动规律及行为观察,为充分了解林睡鼠越冬前的能量储备形式提供饲养参考。将鼠密度监测仪固定在饲养笼具上方,24h连续拍照,采集和分析6-9月年龄在10周内的幼鼠各种活动数据。结果显示:幼鼠一天中超过70%的时间都在窝内度过,大部分时间都蜷缩成一团少有动作;在窝外活动时间多在玩耍,如攀爬笼架。用于进食和饮水的时间不超过全天的2%。林睡鼠幼鼠主要活动时间在21:00-07:00,活动高峰在21:00-03:00之间。幼鼠出生3周后开始出窝活动,哺乳期30d后开始采食,5周后幼鼠有交配玩耍行为。随着日龄的增长,活动高峰从23:00提前到21:00,活动时间也逐渐延长,但9周龄后活动时间逐渐缩短,幼鼠的饮水进食时间与其活动的时间长短较为一致。10周体重可达成年体重的70%。研究表明,林睡鼠在夏秋季节基本是昼伏夜出动物。光照是影响其在外活动的重要因素之一。幼鼠6周后所需的饲料和水量大于成年林睡鼠,在此期间要注意饲料和水的补充。 相似文献
58.
Milena Z. Živković Stošić Niko S. Radulović Marija S. Genčić Vladimir N. Ranđelović 《化学与生物多样性》2021,18(7):e2100285
Herein n-, iso- and anteiso-series of very-long-chained (VLC) alkanes (C21–C35), fatty acid benzyl esters (FABEs; C20–C32), and 2-alkanones (C23–C35) were identified in the wax of Primula veris L. and P. acaulis (L.) L. (Primulaceae). For the very first time in a sample of natural origin, the presence of iso- and anteiso-VLC FABEs and 2-alkanones was unequivocally confirmed by synthetic work, derivatization, and NMR. It should be noted that the studied species produced unusually high amounts of branched wax constituents (e. g., >50 % of 2-alkanones were branched isomers). The domination of iso-isomers, probably biosynthesized from leucine-derived starters, is a unique feature in the Plant Kingdom. The plant organ distribution of these VLC compounds in P. acaulis samples (different habitats and phenological phases) pointed to their possible ecological value. This was supported by a eutectic behavior of binary blends of FABEs and alkanes, as well as by high UV-C absorption by FABEs. 相似文献
59.
Hee Seon Lim Dong-Ho Seo In-Tae Cha Hyunjin Lee Young-Do Nam Myung-Ji Seo 《World journal of microbiology & biotechnology》2018,34(3):44
A putative gene (gadlbhye1) encoding glutamate decarboxylase (GAD) was cloned from Lactobacillus brevis HYE1 isolated from kimchi, a traditional Korean fermented vegetable. The amino acid sequences of GADLbHYE1 showed 48% homology with the GadA family and 99% identity with the GadB family from L. brevis. The cloned GADLbHYE1 was functionally expressed in Escherichia coli using inducible expression vectors. The expressed recombinant GADLbHYE1 was successfully purified by Ni–NTA affinity chromatography, and had a molecular mass of 54 kDa with optimal hydrolysis activity at 55 °C and pH 4.0. Its thermal stability was determined to be higher than that of other GADs from L. brevis, based on its melting temperature (75.18 °C). Kinetic parameters including Km and Vmax values for GADLbHYE1 were 4.99 mmol/L and 0.224 mmol/L/min, respectively. In addition, the production of gamma-aminobutyric acid in E. coli BL21 harboring gadlbhye1/pET28a was increased by adding pyridoxine as a cheaper coenzyme. 相似文献
60.
夏家店等古人骨DNA的提取、扩增及序列分析 总被引:9,自引:0,他引:9
古DNA从距今 2 0 0 0~ 50 0 0年的古代人骨 (编号为 :M89,ⅢM11,ⅢM12和AM4 )中提取出来 ,利用聚合酶链式反应分别对线粒体DNA中MTND4 基因中 112 10~ 11414(2 0 5bp)以及RegionV中 8196~ 83 16(12 1bP)进行了扩增 ,并被测序 .实验结果表明古代人骨中仍存在有大量的遗传信息 ,通过提取、扩增可以得到真实可靠的序列 .对序列进行比较发现 112 4 8,112 4 9,112 83及 112 93为易发生突变的位点 .结果经同源性分析后发现 ,ⅢM11和ⅢM12有很高同源性 ,而M89和AM4与ⅢM11和ⅢM12的同源性却比较低 .这对人类学、考古学及分子进化的研究有重要的辅助作用 . 相似文献