期刊文献+
共找到89篇文章
< 1 2 5 >
每页显示 20 50 100
Mitigation of lead-induced soil toxicity and plant growth promotion by phosphate-solubilizing bacterium Enterobacter hormaechei KR2215 isolated from mangrove rhizosphere 认领 引用
1
作者 Sharmily Chakraborty Ritik Upare Surajit Das 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第5期834-856,共23页
Lead(Pb(Ⅱ))contamination in soil,primarily resulting from mining and agricultural practices,poses environmental and agricultural challenges due to its toxicity and persistence.This study investigated the potential of... Lead(Pb(Ⅱ))contamination in soil,primarily resulting from mining and agricultural practices,poses environmental and agricultural challenges due to its toxicity and persistence.This study investigated the potential of a phosphate solubilizing bacterium(PSB),Enterobacter hormaechei KR2215,isolated from mangrove rhizosphere,for Pb(Ⅱ)remediation and enhancement of Cicer arietinum(chickpea)growth under Pb(Ⅱ)stress.The strain tolerated Pb(Ⅱ)upto 1900 ppm and achieved 93.86%removal in biofilm mode.Biochemical analysis of extracellular polymeric substances(EPS)revealed reduction in carbohydrate content,while protein and lipid levels increased,under Pb(Ⅱ)stress.Electron microscopy coupled with elemental mapping confirmed Pb(Ⅱ)accumulation on the biofilm-EPS matrix,while structural analysis revealed alterations in EPS functional groups upon Pb(Ⅱ)exposure.EPS protein conformation shifted from α-helix(20.2%)to random coil(51.1%)at 1500 ppm Pb(Ⅱ).Phosphate solubilization(682.83±14.26 U m/L)and acid phosphatase activity(46.67±3.39 U m/L)peaked on 3rd day,but declined at higher Pb(Ⅱ)levels.Gene expression analysis indicated upregulation of phoR,pqqE,pgaC,and wzc at 500 ppm,while zntA expression peaked at 1000 ppm(17.82 fold,P<0.0001).Colonization of E.hormaechei KR2215 in the chickpea endorhizosphere was confirmed by scanning electron microscopy(SEM)and enterobacterial repetitive intergenic sequence-based polymerase chain reaction(ERIC-PCR).Inoculated plants exhibited improved growth and reduced Pb(Ⅱ)accumulation in roots(12.18%),shoots(26.81%),leaves(33.30%),and seeds(42.83%).Additionally,it enhanced antioxidant activity and reduced lipid peroxidation,suggesting its potential to improve crop productivity in Pb(Ⅱ)-contaminated soils. 展开更多
关键词 Enterobacter hormaechei KR2215 Phosphate solubilizing bacterium Biofilm-EPS Cicer arietinum Antioxidant activity Lipid peroxidation
暂未订购 下载PDF
细菌Enterobacter dissolvens的直流电解刺激过程 认领 引用 被引量:16
2
作者 佘鹏 宋波 +1 位作者 邢新会 刘铮 《过程工程学报》 EI CAS 北大核心 2006年第1期71-76,共6页
以葡萄糖为唯一碳源,研究了细菌Enterobacterdissolvens在直流电条件下的生长和代谢过程.实验结果表明,当使用盐桥屏蔽电极反应时,细胞生长曲线和葡萄糖代谢速率基本不受电流强度的影响,而当采用铂丝电极时,反应体系中发生水解反应,采用... 以葡萄糖为唯一碳源,研究了细菌Enterobacterdissolvens在直流电条件下的生长和代谢过程.实验结果表明,当使用盐桥屏蔽电极反应时,细胞生长曲线和葡萄糖代谢速率基本不受电流强度的影响,而当采用铂丝电极时,反应体系中发生水解反应,采用10mA电流通电12h后,菌液中细胞的脱氢酶比活力和葡萄糖降解率分别为对照的1.98倍和1.48倍,细胞生长亦有所加快,但在其活力下降时出现大量死亡.扫描电镜照片显示细胞结构受到明显破坏,并发生细胞膜穿孔现象,这表明可能受到了过氧化氢等阳极水解中间产物的刺激作用. 展开更多
关键词 直流电 电解刺激 Enterobacter dissolvens 脱氢酶 葡萄糖 氧化还原电位
暂未订购 下载PDF
孔雀石绿降解菌Enterobacter sp.B-20的分离、鉴定和降解特性研究 认领 引用 被引量:6
3
作者 刘单单 李春生 +4 位作者 杨贤庆 陈胜军 邓建朝 王悦齐 李来好 《南方水产科学》 CAS CSCD 北大核心 2018年第1期50-59,共10页
从受孔雀石绿污染的淡水鱼养殖池塘底泥中,筛选到一株孔雀石绿(C23H25Cl N2,malachite green,MG)高效降解菌,经16S r RNA基因序列及系统进化树分析,初步鉴定为Enterobacter sp.B-20。采用硼氢化钾(KBH4)还原-高效液相色谱法对Enterobact... 从受孔雀石绿污染的淡水鱼养殖池塘底泥中,筛选到一株孔雀石绿(C23H25Cl N2,malachite green,MG)高效降解菌,经16S r RNA基因序列及系统进化树分析,初步鉴定为Enterobacter sp.B-20。采用硼氢化钾(KBH4)还原-高效液相色谱法对Enterobacter sp.B-20的孔雀石绿降解特性进行研究。结果显示,孔雀石绿对菌株的生长有一定抑制作用,24 h内菌株对5~20 mg·L-1孔雀石绿降解率超过97%,12 h内对1~40 mg·L-1孔雀石绿降解率超过82%。菌株的孔雀石绿降解能力随着p H的增加而显著提高,最适降解p H为9。Enterobacter sp.B-20具有较强的耐盐性,在10~40 g·L-1的氯化钠(Na Cl)质量浓度下具有稳定的孔雀石绿降解特性。在高浓度金属离子条件下,Enterobacter sp.B-20表现出较强的耐性及稳定的孔雀石绿降解能力,0.1~1 mmol·L-1铁离子(Fe3+)、0.1~0.5 mmol·L-1铜离子(Cu2+)、0.1 mmol·L-1锰离子(Mn2+)、0.1~1 mmol·L-1铅离子(Pb2+)均能显著提高菌株的孔雀石绿降解率。结果表明,Enterobacter sp.B-20具有在复杂养殖水环境下降解孔雀石绿的应用潜力。 展开更多
关键词 孔雀石绿 Enterobacter sp. 降解特性 高效液相色谱 系统进化树
暂未订购 下载PDF
Enterobacter sp.CV-v对甲基橙的脱色特性与条件优化 认领 引用 被引量:5
4
作者 都林娜 李刚 +4 位作者 卢晓明 闫成进 卢圣佑 泮琇 陈文华 《中国环境科学》 EI CAS CSCD 北大核心 2014年第12期3175-3181,3181-3182,共7页
从浙江温州分离筛选到1株甲基橙高效脱色菌株CV-v,经16S rRNA基因序列分析表明,该菌株属于Enterobacter sp.属.单因素实验结果表明:当pH值在5.0~9.0之间时,培养48h以后,该菌株对甲基橙的脱色率均在80%以上;脱色的最适温度范围为30~40... 从浙江温州分离筛选到1株甲基橙高效脱色菌株CV-v,经16S rRNA基因序列分析表明,该菌株属于Enterobacter sp.属.单因素实验结果表明:当pH值在5.0~9.0之间时,培养48h以后,该菌株对甲基橙的脱色率均在80%以上;脱色的最适温度范围为30~40℃之间;所测碳源中的葡萄糖和麦芽糖、氮源中的牛肉膏和酵母粉对脱色的促进效果最为显著,且Ca2+和Mg2+也对脱色有显著的促进效应;此外,当接种量达到7%(V:V)以后,48h 的脱色率即可达近100%.响应面设计实验结果显示,该菌株对甲基橙脱色的最优操作条件为:pH 8.0,葡萄糖1.7g/L,酵母粉3.0g/L,氯化镁3.0mmol/L及培养温度35.9℃.验证实验结果表明在最优条件下,该菌株在10h内对甲基橙的脱色率可达88.0%.总体而言,该菌株在偶氮染料脱色中的应用潜能较大. 展开更多
关键词 Enterobacter sp. 偶氮染料 脱色特性 响应面设计
暂未订购 下载PDF
Enterobacter sp. CV-v对孔雀石绿的脱色特性及机理研究 认领 引用 被引量:5
5
作者 都林娜 李刚 +3 位作者 杨玉义 许方程 王阳 泮琇 《环境科学学报》 CAS CSCD 北大核心 2016年第10期3675-3682,共8页
采用单因素实验研究了各种操作因素对菌株Enterobacter sp.CV-v降解孔雀石绿的影响.结果表明,在供试碳源中,葡萄糖对脱色的促进效果最为显著,而供试氮源中,酵母粉对脱色的促进效果最优;同时,供试金属离子中,锰离子对脱色的促进效果最优.... 采用单因素实验研究了各种操作因素对菌株Enterobacter sp.CV-v降解孔雀石绿的影响.结果表明,在供试碳源中,葡萄糖对脱色的促进效果最为显著,而供试氮源中,酵母粉对脱色的促进效果最优;同时,供试金属离子中,锰离子对脱色的促进效果最优.在p H=3.0~10.0、温度20~50℃之间时,菌株CV-v对孔雀石绿的12 h脱色率在90%以上.此外,该菌株可在6 h内完全脱色浓度低于500 mg·L-1的孔雀石绿.动力学实验结果表明,该菌株对孔雀石绿脱色的动力学数据与一级动力学模型拟合度最好(R2=0.9755).酶分析实验结果表明,锰过氧化物酶和孔雀石绿还原酶可能与菌株CV-v降解孔雀石绿相关.此外,代谢产物分析实验结果表明,菌株CV-v降解孔雀石绿的主要产物为二甲氨基二苯甲酮和4-羟基-N,N-二甲基苯铵. 展开更多
关键词 Enterobacter sp. 孔雀石绿 脱色特性 代谢产物 代谢机理
暂未订购 下载PDF
Induction of nucleoside phosphorylase in Enterobacter aerogenes and enzymatic synthesis of adenine arabinoside 认领 引用 被引量:5
6
作者 Xiao-kun WEI Qing-bao DING +3 位作者 Lu ZHANG Yong-li GUO Lin OU Chang-lu WANG 《Journal of Zhejiang University-SCIENCE B》 SCIE CAS 2008年第7期520-526,共7页
Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5′-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP cou... Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5′-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP could distinctly increase the activities of purine nucleoside phosphorylase (PNPase), uridine phosphorylase (UPase) and thymidine phosphorylase (TPase) when they were added into medium from 0 to 8 h. In the process of enzymatic synthesis of adenine arabinoside from adenine and uracil arabinoside with wet cells of Enterobacter aerogenes DGO-04 induced by cytidine or CMP, the reaction time could be shortened from 36 to 6 h. After enzymatic reaction the activity of NPase in the cells induced remained higher than that in the cells uninduced. 展开更多
关键词 Nucleoside phosphorylase (NPase) Enterobacter aerogenes Cytidine Cytidine 5'-monophosphate (CMP) Adenine arabinoside
暂未订购 下载PDF
Enterobacter cloacae Z0206细菌胞外多糖的体外抗氧化活性研究 认领 引用 被引量:8
7
作者 徐春兰 钦传光 +1 位作者 牛卫宁 尚晓娅 《天然产物研究与开发》 CAS 2010年第6期1098-1102,共5页
本实验旨在对Enterobacter cloacae Z0206菌进行发酵培养,以制备胞外多糖,并对其体外抗氧化活性进行初步研究。通过产多糖菌E.cloacaeZ0206的深层发酵制备细菌胞外多糖,在此基础上对其清除DPPH自由基、超氧阴离子、抑制羟自由基的能力... 本实验旨在对Enterobacter cloacae Z0206菌进行发酵培养,以制备胞外多糖,并对其体外抗氧化活性进行初步研究。通过产多糖菌E.cloacaeZ0206的深层发酵制备细菌胞外多糖,在此基础上对其清除DPPH自由基、超氧阴离子、抑制羟自由基的能力以及还原力等四个方面进行实验,评价其抗氧化活性。结果表明,深层发酵制备的E.cloacaeZ0206胞外多糖产量为6.62g/L,其在5mg/mL时对DPPH自由基和羟自由基的清除率分别达到61.57%和40.08%。提示E.cloacaeZ0206细菌胞外多糖具有显著的抗氧化能力,具有开发为抗氧化类食品或药品的潜力。 展开更多
关键词 Enterobacter cloacae 胞外多糖 自由基 抗氧化
暂未订购 下载PDF
Sepsis resulting from Enterobacter aerogenes resistant to carbapenems after liver transplantation 认领 引用 被引量:5
8
作者 Chen, Hao Zhang, Ying +3 位作者 Chen, Ya-Gang Yu, Yun-Song Zheng, Shu-Sen Li, Lan-Juan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第3期320-322,共3页
BACKGROUND: Sepsis due to Enterobacter aerogenes (E. aerogenes) is rare after liver transplantation but is also a serious infection that may cause liver abscess. The purpose of this case report is to relate an unusual... BACKGROUND: Sepsis due to Enterobacter aerogenes (E. aerogenes) is rare after liver transplantation but is also a serious infection that may cause liver abscess. The purpose of this case report is to relate an unusual presentation of liver transplantation to show how successive treatment can be an appropriate option in septic patients after liver transplantation. METHOD: We report on a patient with liver transplantation who developed sepsis due to extended spectrum beta-lactamases and AmpC-producing E. aerogenes. RESULTS: A 39-year-old man had a biliary fistula and then was found to have multiple liver abscesses through abdominal ultrasound and an abdominal computed tomography scan, and carbapenem-sensitive E. aerogenes infection was confirmed. The patient was not successfully treated with conservative treatment consisting of intravenous carbapenems, percutaneous transhepatic cholangial drainage, and biliary stent placement by endoscopic retrograde cholangiopancreatography, so a second liver transplantation followed. Carbapenem-resistant E. aerogenes was detected in bile and blood after a five-week course of carbapenem therapy. The patient developed septic shock and multiple organ dysfunction syndrome. CONCLUSIONS: We first report an unusual case of sepsis caused by E. aerogenes after liver transplantation in China. Carbapenem-resistant E. aerogenes finally leads to uncontrolled sepsis with current antibiotics. We hypothesize that the infection developed as a result of biliary fistula and predisposing immunosuppressive agent therapy. Further research is progressing on the aspect of immunomodulation therapy. (Hepatobiliary Pancreat Dis Int 2009; 8: 320-322) 展开更多
关键词 sepsis Enterobacter aerogenes carbapenem therapy
暂未订购 下载PDF
菌株Enterobacter sp.降解除草剂阿特拉津产物测定及降解基因克隆 认领 引用 被引量:3
9
作者 刘丹丹 孙宛玉 +3 位作者 刘畅 马浩珂 王瑞娇 隋宇凡 《河南农业科学》 北大核心 2019年第10期70-76,共7页
为解析除草剂阿特拉津的生物降解过程,采用液相色谱与质谱联用技术对菌株Enterobacter sp.降解阿特拉津的产物进行检测,通过PCR扩增技术克隆降解基因,并利用GO功能富集分析对降解基因功能进行检测。在降解产物中先后检测出羟基阿特拉津... 为解析除草剂阿特拉津的生物降解过程,采用液相色谱与质谱联用技术对菌株Enterobacter sp.降解阿特拉津的产物进行检测,通过PCR扩增技术克隆降解基因,并利用GO功能富集分析对降解基因功能进行检测。在降解产物中先后检测出羟基阿特拉津、氰尿酸和尿素组分,克隆出降解基因L465-RS09425、L465-RS10465、L465-RS12445、L465-RS09100、L465-RS12200和UreA。初步推测菌株Enterobacter sp.在降解基因的作用下,经脱氯、脱烷基、脱氨基、环裂解、脱羧和脲基甲酸水解等过程,将阿特拉津逐步矿化。 展开更多
关键词 阿特拉津 降解产物 降解基因 基因功能 液质联用 Enterobacter sp. 除草剂
暂未订购 下载PDF
Enterobacter Cloacae Z0206细菌胞外富硒多糖的抗氧化活性 认领 引用 被引量:11
10
作者 徐春兰 钦传光 +1 位作者 尚晓娅 牛卫宁 《化学研究》 CAS 2010年第2期64-68,共5页
利用产多糖菌Enterobacter cloacae Z0206(E.cloacaeZ0206)的深层发酵法制备了E.cloacae Z0206细菌富硒多糖;测定了其还原能力和清除1,1-diphenyl-2-picrylhydrazyl(DPPH)自由基、超氧阴离子及羟自由基的能力.结果表明,通过深层富硒发... 利用产多糖菌Enterobacter cloacae Z0206(E.cloacaeZ0206)的深层发酵法制备了E.cloacae Z0206细菌富硒多糖;测定了其还原能力和清除1,1-diphenyl-2-picrylhydrazyl(DPPH)自由基、超氧阴离子及羟自由基的能力.结果表明,通过深层富硒发酵、醇沉离心等制备富硒多糖SEPS的产量为9.28g/L,富硒量为2.314mg/g;E.cloacae Z0206富硒多糖对DPPH自由基和羟自由基具有较好的清除作用,在浓度为5g/L时对DPPH自由基和羟自由基的清除率分别为80.35%和84.26%,并具有较强的还原能力,但其对超氧阴离子自由基的清除能力较差. 展开更多
关键词 Enterobacter cloacae 富硒多糖 细菌胞外多糖 抗氧化活性
暂未订购 下载PDF
功能内生菌株Enterobacter sp. PRd5定殖降低农作物芘污染技术研究 认领 引用 被引量:3
11
作者 刘文韬 朱雪竹 +4 位作者 陈雪梅 孙彦伟 吕百韬 王丹琴 王雪 《南京农业大学学报》 CAS CSCD 北大核心 2020年第2期274-283,共10页
[目的]本文旨在筛选适配的农作物-功能内生菌定殖系统,防治多环芳烃(PAHs)污染。[方法]以芘作为多环芳烃代表,选择空心菜、小麦、不结球白菜、菠菜、茼蒿5种常见农作物,通过在芘降解培养基中添加不同农作物匀浆液,探究目标农作物体内物... [目的]本文旨在筛选适配的农作物-功能内生菌定殖系统,防治多环芳烃(PAHs)污染。[方法]以芘作为多环芳烃代表,选择空心菜、小麦、不结球白菜、菠菜、茼蒿5种常见农作物,通过在芘降解培养基中添加不同农作物匀浆液,探究目标农作物体内物质和体内原有内生菌群对菌株Enterobacter sp.PRd5定殖效率及芘去除的影响,筛选合适的目标农作物-功能内生菌定殖体系。利用定殖培养试验,验证筛选获得的目标农作物-功能菌体系的促生长与降低芘污染的效能。[结果]筛选试验表明,菌株Enterobacter sp.PRd5可产生铁载体和吲哚乙酸(IAA)等促生长因子,促进作物生长。各农作物匀浆液与菌株Enterobacter sp.PRd5的混合液芘去除率从大到小依次为空心菜、小麦、不结球白菜、菠菜、茼蒿,芘去除率分别为83.7%、75.3%、72.6%、70.1%和61.4%。定殖试验显示,菌株Enterobacter sp.PRd5能高效定殖在小麦和空心菜体内,通过提高芘代谢酶活力,降低作物中芘污染。[结论]芘无机盐培养基中添加2%植物匀浆液的细菌培养试验可用于筛选适配的农作物-功能内生菌定殖系统,防治农产品多环芳烃污染。 展开更多
关键词 多环芳烃 农作物 功能植物内生菌定殖 Enterobacter sp.PRd5
暂未订购 下载PDF
Enterobacter sp.SYA2乳糖酶酶学性质研究 认领 引用 被引量:3
12
作者 张卫兵 张炎 +3 位作者 文鹏程 刘芳宁 巨蕾 梁琪 《中国酿造》 CAS 2012年第11期93-98,共6页
采用硫酸铵盐析法对Enterobacter sp.SYA2乳糖酶进行分级沉淀,研究了该酶的最适作用温度、热稳定性、最适作用pH、pH稳定性及金属离子的影响。结果表明:选取硫酸铵的饱和度30%~85%进行分级沉淀,分级沉淀后得到乳糖酶的比活为45.85U/mg... 采用硫酸铵盐析法对Enterobacter sp.SYA2乳糖酶进行分级沉淀,研究了该酶的最适作用温度、热稳定性、最适作用pH、pH稳定性及金属离子的影响。结果表明:选取硫酸铵的饱和度30%~85%进行分级沉淀,分级沉淀后得到乳糖酶的比活为45.85U/mg;该酶最适作用温度为40℃~45℃,在35℃和40℃处理时酶活损失不大,在45℃和50℃处理时酶活损失较大,最适作用pH为6.5,pH在6.0~8.5酶活最为稳定,Mg2+、Mn2+、Na+对该酶有一定激活作用,Zn2+、Cu2、Fe2+对该酶有不同程度的抑制作用,当酶添加量为1U/mL,乳清水解率3h达50%;而添加量为2U/mL时乳清水解率1h达50%。 展开更多
关键词 Enterobacter sp SYA2 乳糖酶 酶学性质
暂未订购 下载PDF
Enterobacter cloacae Z0206生物纳米单质硒的安全性及其相对生物学效价评定 认领 引用 被引量:2
13
作者 胡喻涵 李笑笑 +3 位作者 黄向韵 王凤芹 汪以真 路则庆 《动物营养学报》 CAS CSCD 北大核心 2019年第10期4825-4833,共9页
本试验旨在对Enterobacter cloacae Z0206生物纳米单质硒(BNS)的安全性及其相对生物学效价进行评定。首先,以20只无特定病原体(SPF)级昆明小鼠(雌雄各占1/2,体重18~22 g)为试验动物,采用急性经口毒性试验对BNS的安全性进行评价。在此基... 本试验旨在对Enterobacter cloacae Z0206生物纳米单质硒(BNS)的安全性及其相对生物学效价进行评定。首先,以20只无特定病原体(SPF)级昆明小鼠(雌雄各占1/2,体重18~22 g)为试验动物,采用急性经口毒性试验对BNS的安全性进行评价。在此基础上,选取84只4周龄清洁级Wistar雄性大鼠,随机分为对照组(24只)和硒缺乏组(60只),硒缺乏组饲喂缺硒饲粮(硒含量为0.02 mg/kg),对照组饲喂在缺硒饲粮基础上添加亚硒酸钠(Na2SeO3)的基础饲粮(硒含量为0.15 mg/kg)。饲喂21 d后,从2组随机各选6只大鼠采样,而后将硒缺乏组剩余的54只大鼠随机分为3组,每组6个重复,每个重复3只,分别饲喂在缺硒饲粮基础上添加Na2SeO3、酵母硒(Yeast-Se)和BNS的饲粮,3组饲粮硒含量均为0.15 mg/kg,进行为期35 d的硒补偿试验。结果显示:BNS对小鼠的半数致死剂量(LD 50)>90.46 mg/kg BW(以硒计),具有较高的安全性;经过21 d的硒耗竭,与对照组相比,硒缺乏组大鼠肝脏、肾脏、肌肉中硒含量和血浆、肝脏中谷胱甘肽过氧化物酶(GPx)活性均极显著降低(P0.05),且效果稍优于Yeast-Se。相对于Na2SeO3,以血浆和肝脏中GPx活性,肝脏、肾脏、肌肉中硒含量为评价指标,得出BNS的相对生物学效价分别为112.2%、114.6%、102.0%、155.3%、143.2%,酵母硒的相对生物学效价分别为101.1%、101.7%、103.4%、149.4%、110.6%。由此得出,BNS具有较高的安全性;与Na2SeO3相比,BNS在提高大鼠的采食量、组织硒沉积以及含硒抗氧化酶活性等方面具有明显优势,且BNS的相对生物学效价优于Na2SeO3和Yeast-Se。 展开更多
关键词 Enterobacter cloacae Z0206生物纳米单质硒 相对生物学效价 抗氧化 硒沉积 安全性
暂未订购 下载PDF
Enterobacter cloacae B5产转糖基β-半乳糖苷酶发酵条件优化 认领 引用 被引量:4
14
作者 卢丽丽 肖敏 徐晓东 《应用与环境生物学报》 CAS 北大核心 2008年第1期118-121,共4页
β-半乳糖苷酶是一类非常重要的糖苷水解酶,已被广泛应用于食品工业降低乳制品中的乳糖含量.某些种类的β-半乳糖苷酶还具有转糖基活性,近年来被应用于合成低聚半乳糖和半乳糖苷化合物.通过单因子试验和正交试验,对肠杆菌Enterobacter c... β-半乳糖苷酶是一类非常重要的糖苷水解酶,已被广泛应用于食品工业降低乳制品中的乳糖含量.某些种类的β-半乳糖苷酶还具有转糖基活性,近年来被应用于合成低聚半乳糖和半乳糖苷化合物.通过单因子试验和正交试验,对肠杆菌Enterobacter cloacae B5产生转糖基β-半乳糖苷酶的培养基组成及发酵条件进行了优化.结果表明,以无机盐溶液I(CaCl20.011%、MnSO40.0001%、MgSO4.7H2O0.03%、KH2PO40.005%、FeSO4.7H2O0.003%)、乳糖1.5%、酵母粉2%、蛋白胨0.5%、起始pH8.5的培养基在25℃培养E.cloacaeB5菌株38h,产酶量达到最高值4.663UmL-1,大约是未优化时的3倍.通过优化产酶条件提高了全细胞酶源的酶活量,不仅为功能性低聚半乳糖的生产降低了成本,同时也为商业化β-半乳糖苷酶的大量提纯降低了成本. 展开更多
关键词 Enterobacter cloacae B5 β-半乳糖苷酶 发酵条件 优化
暂未订购 下载PDF
Isolation and identification of a bacteria strain Enterobacter cloacae I7 for degradation of hydrolyzed polyacrylamide 认领 引用 被引量:2
15
作者 马放 李杰训 +3 位作者 魏利 陈忠喜 SHAIK FIRDOZ 赵光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第5期669-672,共4页
A bacteria strain for the degradation of hydrolyzed polyacrylamide (HPAM) was isolated from a curing pot in HPAM distribution station of Daqing Oilfield using Hungate anaerobic technique. The isolate was investigate... A bacteria strain for the degradation of hydrolyzed polyacrylamide (HPAM) was isolated from a curing pot in HPAM distribution station of Daqing Oilfield using Hungate anaerobic technique. The isolate was investigated from morphological, physiological, biochemical and molecular characterization. It is a Gram-negative, shortbacillus, non-spore-forming anaerobic bacteria with an optimum growth at 8.0 pH at 40℃. It can reduce sulfate to I-I2S. Alignment of 16S ribosomal DNA and 16S-23S ribosomal DNA intergenic spacer sequences suggests that this isolate is closely related to the Enterobacter cloacae. The isolate is identified as a new strain belonging to Enterobacter genus, temporarily named as Enterobacter cloacae 17. Analysis results of infrared spectroscopy (IR) show that the bacteria can use HPAM as the only carbon source, change the structure of HPAM polymer surface, and realize the hydrolysis of amide to carboxyl group by hydrolysis mechanism. It can degrade the side chain and change some functional groups, which obviously decreases the viscosity. GC-MS analysis indicates that the determined low-molecular weight degradation products of HPAM are polyacrylamide fragments with duplet bond, epoxy as well as carbonyl group, but most of them are acrylamide oligomer derivatives. 展开更多
关键词 PAM-degrading bacteria strain Hungate anaerobic technique biodegradation Enterobacter cloacae I7
暂未订购 下载PDF
Identification of anrF gene, a homology of admM of andrimid biosynthetic gene cluster related to the antagonistic activity of Enterobacter cloacae B8 认领 引用 被引量:1
16
作者 Xu-Ping Yu Jun-Li Zhu +5 位作者 Xue-Ping Yao Shi-Cheng He Hai-Ning Huang Wei-Liang Chen Yong-Hao Hu De-Bao Li 《World Journal of Gastroenterology》 SCIE CAS 2005年第39期6152-6158,共7页
AIM: To identify the gene (s) related to the antagonistic activity of Enterobacter cloacae B8 and to elucidate its antagonistic mechanism. METHODS: Transposon-mediated mutagenesis and tagging method and cassette P... AIM: To identify the gene (s) related to the antagonistic activity of Enterobacter cloacae B8 and to elucidate its antagonistic mechanism. METHODS: Transposon-mediated mutagenesis and tagging method and cassette PCR-based chromosomal walking method were adopted to isolate the mutant strain (s) of B8 that lost the antagonistic activity and to clone DNA fragments around Tn5 insertion site. Sequence compiling and open reading frame (ORF) finding were done with DNAStar program and homologous sequence and conserved domain searches were performed with BlastN or BlastP programs at www.ncbi.nlm.nih.gov. To verify the gene involved in the antagonistic activity, complementation of a full-length clone of the anrFgene to the mutant B8F strain was used. RESULTS: A 3 321 bp contig around the Tn5 insertion site was obtained and an ORF of 2 634 bp in length designated as anrFgene encoding for a 877 aa polyketide synthase-like protein was identified. It had a homology of 83% at the nucleotide level and 79% ID/87% SIM at the protein level, to the admM gene of Pantoea agglomerans andrimid biosynthetic gene cluster (AY192157). The Tn5 was inserted at 2 420 bp of the gene corresponding to the COG3319 (the thioesterase domain of type I polyketide synthase) coding region on BSF. The antagonistic activity against Xanthomonas oryzae pv. oryzae was resumed with complementation of the full-length anrFgene to the mutant B8F. CONCLUSION: The anrFgene obtained is related to the antagonistic activity of BS, and the antagonistic substances produced by B8 are andrimid and/or its analogs. 展开更多
关键词 Enterobacter doacae 138 Antagonistic mechanism anrFgene Andrimid biosynthetic gene cluster
暂未订购 下载PDF
Anaerobic Biodecolorization of Remazol Dye by a Strain of Enterobacter Isolated from Textile Sludge 认领 引用 被引量:1
17
作者 陈刚 陈晔 +1 位作者 黄满红 陈亮 《Journal of Donghua University(English Edition)》 EI CAS 2011年第3期336-339,共4页
Enterobacter GY-1 gained from a lab scale anaerobic-anoxic-aerobic (A2O) process treating textile effluent can effectively decolorize remazol dye. Under anaerobic condition, 91% of this remazol dye is decolorized, whi... Enterobacter GY-1 gained from a lab scale anaerobic-anoxic-aerobic (A2O) process treating textile effluent can effectively decolorize remazol dye. Under anaerobic condition, 91% of this remazol dye is decolorized, which is much higher than under aerobic condition. The optimum pH is 7 and the optimum temperature is 35 ℃ for the remazol dye decolorization by GY-1. Anthraquinone dyes and monoazo dyes are decolorized more efficiently by GY-1 than other dyes tested decolorized. GY-1 can not decolorize the remazol dye when it is the sole carbon source. Microbial cometabolism and decolorization of dye take place in the presence of some other carbon source called cometabolic substrate. The cometabolic substrate can be glucose, starch, peptone, beef extract, etc. The change of molecular structure of the dye before and after decolorized by GY-1 is studied by UV-Vis absorption spectrum. The results indicate that its molecular structure is changed evidently. 展开更多
关键词 Enterobacter GY-1 remazol dye decolorization biodegradation
暂未订购 下载PDF
Vigna radiata var. GM4 Plant Growth Enhancement and Root Colonization by a Multi-Metal-Resistant Plant Growth-Promoting Bacterium Enterobacter sp. C1D in Cr(VI)-Amended Soils 认领 引用 被引量:2
18
作者 Gangavarapu SUBRAHMANYAM Rakesh Kumar SHARMA +1 位作者 Gattupalli Naresh KUMAR Gattupalli ARCHANA 《Pedosphere》 SCIE CAS CSCD 2018年第1期144-156,共13页
Contamination of agricultural soils by heavy metals has become a major concern due to their toxic effects on plant growth,symbiosis and consequently the yields of crops. In the present study, to enhance plant growth i... Contamination of agricultural soils by heavy metals has become a major concern due to their toxic effects on plant growth,symbiosis and consequently the yields of crops. In the present study, to enhance plant growth in Cr(VI)-amended soils, novel metalresistant plant growth-promoting bacteria(PGPB) were isolated from a soil contaminated with industrial waste effluent. One of the bacterial isolates, identified as Enterobacter sp. C1 D by 16 S r RNA gene sequencing, was found to be multi-metal resistant in nature with excellent plant growth-promoting(PGP) traits. Mung bean(Vigna radiata var. GM4) inoculation with Enterobacter sp.C1 D significantly(P &lt; 0.01) increased root and shoot length, shoot and root weight, and chlorophyll content in a range of Cr(VI)treatments. Plant tolerance towards Cr(VI) measured as effective concentration showed higher values with Enterobacter sp. C1 Dtreated plants compared to un-inoculated plants. Root colonization study was also carried out using green fluorescence protein-labeled Enterobacter sp. C1 D under a hydroponic system. Confocal laser scanning microscopy of the plant roots showed heavy bacterial loads on the surface of the plant root specifically at the root tip and the point of root hair/lateral root formation. The results of PGP traits showed that elevated indole acetic acid levels and 1-aminocyclopropane-1-carboxylate deaminase activity enabled Enterobacter sp. C1 D to enhance V. radiata growth in Cr(VI)-amended soils, whereby it significantly increased plant tolerance towards elevated Cr(VI) concentrations. 展开更多
关键词 chromium(VI) Enterobacter sp C1D heavy metal metal toxicity plant tolerance
暂未订购 下载PDF
聚丙烯酰胺降解菌株Enterobacter cloacae的分离鉴定 认领 引用 被引量:1
19
作者 张兴福 向阳 +1 位作者 徐德会 陈忠喜 《哈尔滨商业大学学报(自然科学版)》 CAS 2010年第6期671-674,共4页
应用厌氧Hungate技术,从大庆油田聚合物配注站的熟化罐水溶液中分离到一株聚丙烯酰胺降解菌株.对该菌株进行形态、生理生化、分子生物学鉴定结果表明,菌株为G-,短杆状,无芽孢,最佳pH值为8.0,最适生长温度为40℃,具有硫酸盐还原功能,产H... 应用厌氧Hungate技术,从大庆油田聚合物配注站的熟化罐水溶液中分离到一株聚丙烯酰胺降解菌株.对该菌株进行形态、生理生化、分子生物学鉴定结果表明,菌株为G-,短杆状,无芽孢,最佳pH值为8.0,最适生长温度为40℃,具有硫酸盐还原功能,产H2S,严格厌氧,通过16S rDNA和16S^23S rDNA间隔区序列鉴定,菌株与Enterobacter cloacae有极高的相似性.初步鉴定为Enterobact-er中的新种,暂时命名为Enterobacter cloacae.红外光谱分析结果表明,菌株以聚丙烯酰胺为惟一碳源,菌株作用前后表面结构发生变化,分子链上的酰胺基水解成羧基,降解侧链,部分官能团发生改变,溶液黏度下降效果显著;GC-MS初步分析聚合物发生断链,低分子质量化合物除含双键、环氧和羰基的聚丙烯酰胺碎片外,大多属于一般丙烯酰胺低聚体的衍生物. 展开更多
关键词 聚丙烯酰胺降解菌 生物降解 Enterobacter cloacae I7 系统发育
暂未订购 下载PDF
细菌Enterobacter dissolvens的电解刺激效应研究 认领 引用 被引量:1
20
作者 宋波 《生物技术》 CAS 北大核心 2009年第1期84-87,共4页
以葡萄糖为惟一碳源,研究了细菌Enterobacter dissolvens在直流电条件下的生长和代谢过程。结果,在直流电刺激过程中,反应体系中发生水解反应。当屏蔽阴极电极时,阳极产生的氧气使细胞生长曲线和葡萄糖代谢速率急剧下降,菌液葡萄糖的降... 以葡萄糖为惟一碳源,研究了细菌Enterobacter dissolvens在直流电条件下的生长和代谢过程。结果,在直流电刺激过程中,反应体系中发生水解反应。当屏蔽阴极电极时,阳极产生的氧气使细胞生长曲线和葡萄糖代谢速率急剧下降,菌液葡萄糖的降解率和脱氢酶活性分别为对照参比的0.45倍和0.06倍,细胞浓度明显的下降;而屏蔽阳极电极时,阴极产生的氢气通过改变环境而使得细胞生长曲线和葡萄糖代谢急速上升,菌液葡萄糖的降解率和脱氢酶活性分别为对照参比的3倍和4.5倍,细胞浓度呈现明显的增长。分析原因可能是电极反应导致菌液的物化性质改变所致。 展开更多
关键词 直流电 电解刺激 Enterobacter dissolvens 脱氢酶 葡萄糖 氧化还原电位
暂未订购 下载PDF
上一页 1 2 5 下一页 到第
在线咨询 使用帮助 返回顶部 意见反馈