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N-Acylhomoserine Lactones (AHLs), QseB/C Gene Detection, Virulence Factors and Antibiotics Resistance of <i>Aeromonas hydrophila</i>
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作者 Emmanuel Konadu Sarkodie Shuxin Zhou Weihua Chu 《Advances in Microbiology》 2019年第5期495-506,共12页
The aim of this research was to detect the N-acyl homoserine lactones (AHLs) production and QseB/C gene of Aeromonas hydrophila. We analyzed the potentials of these isolates of Aeromonas hydrophila in causing biofilm ... The aim of this research was to detect the N-acyl homoserine lactones (AHLs) production and QseB/C gene of Aeromonas hydrophila. We analyzed the potentials of these isolates of Aeromonas hydrophila in causing biofilm formation, hemolysis, protease, and lipase. The antibiotic susceptibility of the 15 Aeromonas hydrophila isolates was also investigated. The detection of AHLs was carried out using the Chromobacterium violaceum strain CV026 as biosensors. The isolated strains were tested for the reaction of C. violaceum CV026 by cross-streaking on an agar plate. Production of AHLs was determined by the diffusing via the agar plates and the tinge of the biosensor strains. All isolated strains produced AHLs. A polymerase chain reaction (PCR) showed the isolated strains had qseB and qseC genes. Susceptibility tests of A. hydrophila isolates were administered against 25 different antibiotic disks representing 12 classes of antibiotics. The strains were highly resistant to β-Lactam with 96.7% showing resistibility, whereas 97.7% susceptibility was found towards Aminoglycoside class of the antibiotic used. 60% showed intermediate resistant to Polypeptide. 100% of the strains showed no resistant to Aminoglycoside, Polypeptide, Monobactam, and Carbapenems class of antibiotics. Each of the isolates was found to be associated with at least one virulent factor. Our results clearly demonstrated that there is a presence of QseB/C genes in A. hydrophila and also produces AHLs molecule and virulence factors. The investigated isolates showed the pathogenic potential of Aeromonas hydrophila which makes it a serious threat to public health. 展开更多
关键词 AEROMONAS HYDROPHILA Antibiotic Susceptibility Virulence Factors Biofilm Formation N-Acyl HOMOSERINE lactoneS (AHLs)
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Histone Deacetylation Modifier Induced One New Resorcylic Acid Lactone 7′(Z)-zeaenol from the Zoanthid-Derived Fungus Cochliobolus lunatus
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作者 ZHANG Zhenkun WANG Jiaxiang +5 位作者 CAO Fei ZHOU Xiaojian WU Jingshuai FU Xiumei CHEN Min WANG Changyun 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期198-204,共7页
Chemical epigenetic manipulation was applied to the zoanthid-derived fungus Cochliobolus lunatus(TA26-46)with a histone deacetylation modifier(100μmol L^(−1) nicotinamide),resulting in the isolation of a new 14-membe... Chemical epigenetic manipulation was applied to the zoanthid-derived fungus Cochliobolus lunatus(TA26-46)with a histone deacetylation modifier(100μmol L^(−1) nicotinamide),resulting in the isolation of a new 14-membered resorcylic acid lactone named 7′(Z)-zeaenol(1),together with six known analogues(2−7)from the treated broth.The planar structure of 1 was determined by comprehensive NMR spectroscopy and HRESIMS data.The absolute configuration of 1 was elucidated by ECD spectrum,^(13)C NMR shift calculations,and on the basis of biogenetic considerations.Compound 5 exhibited cytotoxic activity against the human tumor cell lines A549,HCT-116,HT-29,Hela,MCF-7,and K562 with the IC_(50) values ranging from 2.54 to 7.44μmolL^(−1). 展开更多
关键词 Cochliobolus lunatus 14-membered resorcylic acid lactone chemical epigenetic manipulation cytotoxic activity
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Degradation of N-Acyl Homoserine Lactone Quorum Sensing Signals by Bacillus thuringiensis AHL Lactonase
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作者 Waeel H. Alramadhan Anthony Ejiofor Terrance Johnson 《Advances in Microbiology》 2023年第11期526-538,共13页
Bacterial cells rely on signaling molecules to communicate with others from the same species and induce certain genes in a process known as quorum sensing (QS). A common molecule is N-acyl homoserine lactone (AHL) whi... Bacterial cells rely on signaling molecules to communicate with others from the same species and induce certain genes in a process known as quorum sensing (QS). A common molecule is N-acyl homoserine lactone (AHL) which is responsible for the expression of virulence and other factors that allow the organisms to compete in a given environment. On the other hand, other bacteria produce certain enzymes such as AHL-lactonase that break down AHL molecules and prevent gene expression of these factors. The aim of this work was to examine the level of degradation of AHL molecules by AHL-lactonase in 62 Bacillus thuringiensis (Bt) strains isolated from Middle Tennessee, Mississippi, and Alabama. N-hexanoyl-homoserine lactone (C<sub>6</sub>-HSL) and N-3-oxo-hexanoyl homoserine lactone (3-oxo-C<sub>6</sub>-HSL), which cause Chromobacterium violaceum (CV026) to produce a purple pigment were tested at different concentrations to view the Bt lactonase activity. In addition, PCR was used to test for the presence of the lactonase gene. The results showed that among the 62 Bt strains, there were 58 that possessed the AHL-lactonase (aiiA) gene and 48 strains were able to degrade C<sub>6</sub>-HSL. At high concentrations of AHL, only 13 strains were able to completely degrade C6-HSL. In addition, degradation of 3-oxo-C<sub>6</sub>-HSL was weak compared to C<sub>6</sub>-HSL. The results also revealed that AHL lactonase was thermostable, and it was concluded that the level of degradation varies in Bt strains. Only 13 of the strains studied have potent inhibitory activity against C<sub>6</sub>-HSL, which may be good to be used in field applications to control agricultural pest. 展开更多
关键词 Quorum Sensing Quorum Sensing Inhibitor N-Acyl Homoserine lactone AHL lactonase Bacillus thuringiensis CV026
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Study on Induction of Microcystis aeruginosa Cell Apoptosis by Signal Molecule N-acetyl-homoserine Lactones(AHLs) 被引量:3
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作者 郭丽红 陈小兰 +1 位作者 黄子玥 张岸 《Agricultural Science & Technology》 CAS 2011年第1期30-32,共3页
[Objective]The relationship between signal molecule N-acety-homoserine lactones(AHLs) and Microcystis aeruginosa cell apoptosis was studied.[Method]With M.aeruginosa as the test materials treated by 5 μmol/L N-acet... [Objective]The relationship between signal molecule N-acety-homoserine lactones(AHLs) and Microcystis aeruginosa cell apoptosis was studied.[Method]With M.aeruginosa as the test materials treated by 5 μmol/L N-acety-homoserine lactones(AHLs),the morphology of cell apoptosis was observed through staining with DAPI.[Result]Microcystis aeruginosa cell apoptosis was induced by signal molecule N-acetyhomoserine lactones(AHLs) with the concentration of 1 μmol/L to inhibit the growth and proliferation of Microcystis aeruginosa.[Conclusion] The results provided the important scientific basis and new management ideas for the treatment of water bloom of Microcystis aeruginosa. 展开更多
关键词 N-acety-homoserine lactones(AHLs) Microcystis aeruginosa Cell apoptosis
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前列腺素关键中间体——手性Corey Lactone的合成研究进展 被引量:4
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作者 齐创宇 何煦昌 《合成化学》 CAS CSCD 2006年第6期539-545,551,共8页
综述了前列腺素的关键手性中间体———Corey lactone的制备方法,重点阐述了Corey lactone的外消旋体拆分法,不对称合成法及手性源原料法的最新研究进展。参考文献28篇。
关键词 前列腺素 中间体 Corey内酯 手性合成 综述
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Sesquiterpene Lactones from Elephantopus scaber 被引量:6
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作者 Qiao Li LIANG Zhi Da MIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期343-344,共2页
A new germacranolide sesquiterpene lactone, isoscabertopin, was isolated from Elephantopus scaber together with the known scabertopin. Their structures were determined by spectroscopic methods.
关键词 Elephantopus scaber COMPOSITAE germacranolide sesquiterpene lactone isoscabertopin.
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A new cassane diterpenoid lactone from the seed of Caesalpinia minax 被引量:7
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作者 Yan Cheng Li Yan Ma +3 位作者 Jian Hua Miao Xu Dong Xu Jing Quan Yuan Jun Shan Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期444-446,共3页
A new cassane diterpenoid lactone was isolated from the seed of Caesalpinia minax. On the basis of spectral evidences, its structure was established as 12α-methoxyl, 5α, 14β-dihydroxy-1α, 6α, 7β-triacetoxycass-1... A new cassane diterpenoid lactone was isolated from the seed of Caesalpinia minax. On the basis of spectral evidences, its structure was established as 12α-methoxyl, 5α, 14β-dihydroxy-1α, 6α, 7β-triacetoxycass-13(15)-en-16, 12-olide. 展开更多
关键词 CAESALPINIA Caesalpinia minax Cassane diterpenoid lactone
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A New Sesquiterpene Lactone from Ainsliaea bonatii 被引量:5
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作者 Jian Xin PU Jing Feng ZHAO +3 位作者 Xiao Dong YANG Shuang Xi MEI Hong Bin ZHANG Liang LI School of Pharmacy, Yunnan University, Kunming 650091 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第12期1454-1456,共3页
A new sesquiterpene lactone, Ainsliaolide A, was isolated from Ainsliaea bonatii. Thestructure was determined on the basis of spectral data.
关键词 Ainsliaea bonatii sesquiterpene lactone ainsliaolide A diaspanolide A.
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Eupatoranolide, a New Sesquiterpene Lactone from Eupatorium adenophorum 被引量:4
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作者 Zhi Hui DING Jing Kai DING(Laboratory of phytochemistry, Kunming Institute of Botany, Academia Sinica. Kunming 650204) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期491-494,共4页
A new sesquiterpene lactone eupatoranolide was isolated from the flowers of Eupatorium adenophorum, its structure was elucidated as 2 beta-acetoxy-(7 alpha, 9 beta H)-3.6(11)-cadinadien-12(7)-olide by spectral analysis.
关键词 Eupatorium adenophorum cadinene sesquiterpene lactone eupatoranolide
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A new ent-labdane diterpenoid lactone from Andrographis paniculata 被引量:3
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作者 Xiao Chi Ma Zhan Ping Gou +4 位作者 Chang Yuan Wang Ji Hong Yao Xiu Lan Xin Yuan Lin Ke Xin Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期587-589,共3页
A new ent-labdane diterpenoid lactone was isolated from Andrographis paniculata.Its structure was identified on the basis of spectral data including 2D NMR.
关键词 Andrographis paniculata Ent-labdane diterpenoid lactone
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Fenugreek lactone attenuates palmitate-induced apoptosis and dysfunction in pancreatic β-cells 被引量:2
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作者 Jing Gong Hui Dong +7 位作者 Shu-Jun Jiang Ding-Kun Wang Ke Fang De-Sen Yang Xin Zou Li-Jun Xu Kai-Fu Wang Fu-Er Lu 《World Journal of Gastroenterology》 SCIE CAS 2015年第48期13457-13465,共9页
AIM: To investigate the effect of fenugreek lactone(FL) on palmitate(PA)-induced apoptosis and dysfunction in insulin secretion in pancreatic NIT-1 β-cells. METHODS: Cells were cultured in the presence or absence of ... AIM: To investigate the effect of fenugreek lactone(FL) on palmitate(PA)-induced apoptosis and dysfunction in insulin secretion in pancreatic NIT-1 β-cells. METHODS: Cells were cultured in the presence or absence of FL and PA(0.25 mmol/L) for 48 h. Then, lipid droplets in NIT-1 cells were observed by oil red O staining, and the intracellular triglyceride content was measured by colorimetric assay. The insulin content in the supernatant was determined using an insulin radioimmunoassay. Oxidative stress-associated parameters, including total superoxide dismutase, glutathione peroxidase and catalase activity and malondialdehyde levels in the suspensions were also examined. The expression of upstream regulators of oxidative stress, such as protein kinase C-α(PKC-α), phospho-PKC-α and P47 phox, were determined by Western blot analysis and real-time PCR. In addition, apoptosis was evaluated in NIT-1 cells by flow cytometry assays and caspase-3 viability assays.RESULTS: Our results indicated that compared to the control group, PA induced an increase in lipid accumulation and apoptosis and a decrease in insulin secretion in NIT-1 cells. Oxidative stress in NIT-1 cells was activated after 48 h of exposure to PA. However, FL reversed the above changes. These effects were accompanied by the inhibition of PKC-α, phosphoPKC-α and P47 phox expression and the activation of caspase-3. CONCLUSION: FL attenuates PA-induced apoptosis and insulin secretion dysfunction in NIT-1 pancreatic β-cells. The mechanism for this action may be associated with improvements in levels of oxidative stress. 展开更多
关键词 FENUGREEK lactone Diabetes OXIDATIVESTRESS Insulin SECRETION Apoptosis
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A new nor-sesquiterpene lactone from Ainsliaea fulvioides 被引量:2
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作者 Yan Wang Ming Lu Xu +6 位作者 Hui Zi Jin Jian Jun Fu Xiao Jia Hu Jiang Jiang Qin Shi Kai Yan Yun Heng Shen Wei Dong Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期586-588,共3页
A new nor-sesquiterpene lactone ainsliatone A (1) was isolated from the aerial parts of Ainsliaeafulvioides. Its structure was established by the basis of spectroscopic methods and single-crystal X-ray diffraction a... A new nor-sesquiterpene lactone ainsliatone A (1) was isolated from the aerial parts of Ainsliaeafulvioides. Its structure was established by the basis of spectroscopic methods and single-crystal X-ray diffraction analysis. 展开更多
关键词 Ainsliaea fulvioides Ainsliatone A Nor-sesquiterpene lactone X-ray diffraction
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A new nine-membdered lactone from a marine fungus Cladosporium sp.F14 被引量:2
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作者 Cheng Hai Gao Xu Hua Nong +3 位作者 Shu Hua Qi Xiong Ming Luo Si Zhang Hai Rong Xiong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第11期1355-1357,共3页
A new nine-membered lactone,cladospolide E(1),was isolated from a culture broth of a marine fungus Cladosporium sp.F14. The structure of compound 1 was determined on the basis of extensive spectroscopic analysis,inc... A new nine-membered lactone,cladospolide E(1),was isolated from a culture broth of a marine fungus Cladosporium sp.F14. The structure of compound 1 was determined on the basis of extensive spectroscopic analysis,including 1D and 2D NMR data. 展开更多
关键词 Cladosporium sp Marine fungus Nine-membered lactone Cladospolide E
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A new ent-labdane eiterpenoid lactone from Andrographis paniculata 被引量:1
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作者 Xiao Chi Ma Bao Jing Zhang +3 位作者 Sha Deng Shan Shan Huang Ke Xin Liu Jing Ming Jia 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第3期317-319,共3页
A new ent-labdane diterpenoid lactone with a new natural product was isolated from Andrographis paniculata. Their structures were elucidated on the basis of spectral evidences including 2D NMR.
关键词 Andrographis paniculata Ent-labdane diterpenoid ACANTHACEAE lactone
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New Sesquiterpene Lactones from Carpesium Lipskyi 被引量:1
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作者 SHI Yan ping YANG Chao JIA Zhong jian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期115-117,共3页
NopreviousworkonthechemicalconstituentsofCarpesiumlipskyi(family:Compositae),usedasfolkmedicine,sinceancient... NopreviousworkonthechemicalconstituentsofCarpesiumlipskyi(family:Compositae),usedasfolkmedicine,sinceancienttimes,forrelievin... 展开更多
关键词 Carpesium Lipskyi COMPOSITAE Sesquiterpene lactones GERMACRANOLIDES
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Effects of coriaria lactone-activated,astrocyte-conditioned medium on estrogen receptor and progesterone receptor expression in rat cortical and hippocampal neurons 被引量:1
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作者 Jie Rong Shuhua Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期144-147,共4页
BACKGROUND: Coriaria lactone-activated astrocytes released bioactive substances that eventually caused epilepsy. OBJECTIVE: It has been suggested that activated astrocytes alter the expression of the estrogen recept... BACKGROUND: Coriaria lactone-activated astrocytes released bioactive substances that eventually caused epilepsy. OBJECTIVE: It has been suggested that activated astrocytes alter the expression of the estrogen receptor and progesterone receptor by releasing bioactive substances during epilepsy, thereby affecting neuronal activity in the brain. This study was designed to observe the expression of the estrogen receptor and the progesterone receptor in rat brain following lateral ventricle injection of coriaria lactone-activated, astrocyte-conditioned medium. DESIGN AND SETTING: This immunohistochemical, randomized, controlled, animal study was conducted at the Department of Pathology, Hospital Affiliated to Binzhou Medical College, China. MATERIAL: Coriaria lactone was provided by Huaxi Pharmaceutical Factory, China. METHODS: Forty adult, healthy, male, Sprague Dawley rats were randomly assigned into two groups. Astrocyte-conditioned medium (10 μ L) was injected into rat lateral ventricle in the control group (n = 8). Coriaria lactone-activated, astrocyte-conditioned medium (10 μL) was infused into the rat lateral ventricle in the coriaria lactone group (n = 32). At 2, 4, 8 and 12 hours following injection, rats were sacrificed and subjected to immunohistochemistry. Eight rats were studied at each time point. MAIN OUTCOME MEASURES: Behavioral changes were observed in rats of both groups. Expression of the estrogen receptor and the progesterone receptor in rat cortical and hippocampal neurons was measured using immunohistochemistry. RESULTS: Four hours after injection, estrogen receptor levels in rat cortical and hippocampal neurons were significantly higher in the coriaria lactone group than in the control group (P 〈 0.05). Progesterone receptor levels were significantly lower in the coriaria lactone group than in the control group (P 〈 0.05). Seizures were not observed in the control group. In the coriaria lactone group, convulsions appeared 30 minutes after injection; seizures reached grade Ⅲ at 45 minutes rat behavior was nearly normal at 2 hours. CONCLUSION: Activated astrocytes can induce seizures in the rat by enhancing estrogen receptor expression and decreasing progesterone receptor expression in cerebral cortical and hippocampal neurons. 展开更多
关键词 estrogen receptor progesterone receptor SEIZURE coriaria lactone astrocyte- conditioned medium
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Sesquiterpene Lactone Glycosides from Carpesium macrocephalum 被引量:1
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作者 ChaoYANG YanPingSHI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第3期247-248,共2页
Two new sesquiterpene lactone glycosides were isolated from the seeds of Carpesium macrocephalum. Their structures were elucidated as 2-O--D-glucopyranosy-5? 11?H- eudesma-4 (15)-en-12, 8?olide and 2 ?O--D-glucopyran... Two new sesquiterpene lactone glycosides were isolated from the seeds of Carpesium macrocephalum. Their structures were elucidated as 2-O--D-glucopyranosy-5? 11?H- eudesma-4 (15)-en-12, 8?olide and 2 ?O--D-glucopyranosy-5?H-eudesma-4 (15), 11 (13)- dien-12, 8?olide by spectral methods (HRMS, 1 D and 2 D NMR). 展开更多
关键词 Carpesium macrocephalum COMPOSITAE eudesmanolide sesquiterpene lactone gly- cosides.
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Synthesis of macrocyclic lactones with methoxysulfonyl side chain 被引量:1
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作者 Chuan Jin Hou Xiao Mei Liang Jing Ping Wu Dao Quan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第4期403-405,共3页
Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloai... Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates(1)in total yields of 45 and 57%,respectively. 展开更多
关键词 Macrocyclic lactone Ring enlargement α-Hydroxypropyl-α-methoxysulfonylcycloalkanones SYNTHESIS
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Effect of Coriaria Lactone on Membrane Potential of Hippocampal Neurons in Rats 被引量:1
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作者 胡谋先 王阿敬 +2 位作者 刘长金 吴惠敏 朱长庚 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2000年第2期103-105,共3页
Intracellular recording method of electrophysiology was used to study the effect of microinjection of coriaria lactone (CL) into hippocampus on membrane potential of hippocampal neurons in rats. The membrane potentia... Intracellular recording method of electrophysiology was used to study the effect of microinjection of coriaria lactone (CL) into hippocampus on membrane potential of hippocampal neurons in rats. The membrane potential in 34 neurons of 12 rats were recorded. The results showed that CL induced depolarization of all of 34 neurons examined. Among the 34 neurons, 15 had paroxysmal depolarization accompanied by spike discharge in cluster and spike discharge in cluster ceased when membrane was hyperpolarized, 7 showed continuous depolarization accompanied by continuous spike discharge and 12 had only depolarizing response. The results suggest that injection of CL into hippocampus may lead to an increase of excitability of local neurons accompanied by different patterns of epileptioform discharge. 展开更多
关键词 coriaria lactone HIPPOCAMPUS DEPOLARIZATION EPILEPSY
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Monooxygenase Gene from Acinetobacter sp. C42 Inactivates the Acyl Homoserine Lactone Quorum Sensing Signal 被引量:1
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作者 Aili TUREKE 《Agricultural Biotechnology》 CAS 2012年第5期30-33,39,共5页
[ Objective] This study aimed to investigate the function of aliD gene in the inactivation of AHLs. [ Method ] A bacterial isolate, Acinetobacter sp. CA2 from soil, is capable of inactivation of AHLs. A gene designed ... [ Objective] This study aimed to investigate the function of aliD gene in the inactivation of AHLs. [ Method ] A bacterial isolate, Acinetobacter sp. CA2 from soil, is capable of inactivation of AHLs. A gene designed as aliD, which is responsible for AHL-quenching activity and exhibits high similarity with Mo- nooxygenase genes, was cloned from the genomic library of Acinetobacter sp. CA2. [ Result ] The aliD gene in-frame deletion mutant, CA2 AliD, impaired its AHLs inactivating function when mixed with N-(3-oxooctanoyl) -L-homosefine lactone (30C8-HSL). Expression of AliD in plant pathogenic bacterium Pectobacterium ca- rotovorum subsp, carotovorum Z3-3 significantly reduced the AHLs production and the extracellular pectolytic enzyme activities, and attenuated soft rot disease symptoms on the plants tested, including potato, Chinese cabbage, radish and cabbage. [ Conclusion ] Our study suggests that the aliD gene complemented strain CA2-AliD showes a similar AHLs inactivating function. 展开更多
关键词 Quorum sensing ACINETOBACTER Qcyl-homoserine lactones MONOOXYGENASE
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