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Promotion mechanism of self-transmissible degradative plasmid transfer in maize rhizosphere and its application in naphthalene degradation in soil
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作者 Qiuyan Jiang Wenwei Lu +5 位作者 Lei Zhang Yeqing Jin Yujing Wang Jun Chen Ziyi Ye Ming Xiao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第5期240-252,共13页
Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much attention.Plant-microbe remediation is an effective way to promote pollutant biodegradation;howeve... Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much attention.Plant-microbe remediation is an effective way to promote pollutant biodegradation;however,some pollutants,such as naphthalene,are harmful to plants and result in inefficient plant-microbe remediation.In this study,trans-fer of a TOL-like plasmid,a self-transmissible plasmid loaded with genetic determinants for pollutant degradation,among different bacteria was examined in bulk and rhizosphere soils as well as addition of maize root exudate and its artificial root exudate(ARE).The results showed that the numbers of transconjugants and recipients as well as bacterial metabolic activities,such as xylE mRNA expression levels and catechol 2,3-dioxygenase(C23O)activ-ities of bacteria,remained high in rhizosphere soils,when compared with bulk soils.The number of transconjugants and bacterial metabolic activities increased with the increasing exudate and ARE concentrations,whereas the populations of donor and recipient bacteria were substantially unaltered at all concentrations.All the experiments consistently showed that a certain number of bacteria is required for self-transmissible plasmid transfer,and that the increased plasmid transfer might predominantly be owing to bacterial metabolic activ-ity stimulated by root exudates and ARE.Furthermore,ARE addition increased naphthalene degradation by transconjugants in both culture medium and soil.Thus,the combined action of a wide variety of components in ARE might contribute to the increased plasmid transfer and naphthalene degradation.These findings suggest that ARE could be an effectively al-ternative for plant-microbe remediation of pollutants in environments where plants cannot survive. 展开更多
关键词 Degradative plasmid transfer Naphthalene degradation RHIZOSPHERE Root exudates
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亚抑菌浓度万古霉素对质粒接合转移的促进作用
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作者 游祖姣 曾福鑫 +1 位作者 王志强 肖霞 《中国兽医杂志》 CAS 北大核心 2024年第5期78-85,共8页
为了分析亚抑菌浓度万古霉素对质粒接合转移的影响,本试验建立了以大肠杆菌(E.coli)J53作为受体菌,携带RP4-7质粒的E.coli DH5α和携带mcr-1阳性IncI2质粒的临床菌株E.coli LD67-1为供体菌的接合转移模型,测定亚抑菌浓度的万古霉素对接... 为了分析亚抑菌浓度万古霉素对质粒接合转移的影响,本试验建立了以大肠杆菌(E.coli)J53作为受体菌,携带RP4-7质粒的E.coli DH5α和携带mcr-1阳性IncI2质粒的临床菌株E.coli LD67-1为供体菌的接合转移模型,测定亚抑菌浓度的万古霉素对接合转移的影响,并通过细胞膜通透性检测、扫描电子显微镜观察、活性氧(ROS)检测和实时荧光定量PCR(RT-qPCR)方法探究其内在机制。结果显示,与空白对照组相比,亚抑菌浓度万古霉素可显著提高RP4-7质粒和mcr-1阳性IncI2质粒的接合转移频率(P<0.05);N-苯基-1-萘胺(NPN)和碘化丙啶(PI)探针检测显示,亚抑菌浓度万古霉素可使受体菌细胞内、外膜通透性增加,供体菌细胞外膜通透性增加;扫描电子显微镜观察显示,经1/4最小抑菌浓度(MIC)万古霉素处理后接合细菌细胞膜发生损伤;ROS检测结果显示,与空白对照组相比,虽然经1/4 MIC万古霉素处理的受体菌的ROS表达水平显著上调(P<0.05),但1/8 MIC万古霉素处理后,供体菌和受体菌的ROS水平均无显著变化(P>0.05);RT-qPCR结果显示,与空白对照组相比,亚抑菌浓度万古霉素显著上调了供体菌和受体菌的孔蛋白基因ompF和ompC的mRNA表达水平(P<0.05),极显著上调了trbBp基因(调控细菌间形成“连接桥”)的mRNA表达水平(P<0.01),显著上调了细菌SOS响应(SOS response)相关基因recA、recN、ruvA和lexA的mRNA表达水平(P<0.05)。结果表明,亚抑菌浓度的万古霉素可能通过提高细菌细胞膜通透性,触发SOS响应,促进接合转移“连接桥”形成等方式促进RP4-7质粒和mcr-1阳性IncI2质粒的接合转移过程。 展开更多
关键词 亚抑菌浓度 万古霉素 质粒接合转移 mcr-1
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除草剂对质粒介导ARGs接合转移的影响及机制
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作者 孙凤飞 王秀 +2 位作者 毛雨梦 刘珂 刘娟 《中国环境科学》 EI CAS CSCD 北大核心 2024年第11期6426-6434,共9页
本研究以同时携带四环素、氨苄青霉素和卡那霉素3种抗生素抗性基因(ARGs)的可移动质粒RP4为供体质粒(保存于供体菌E.coli DH5α中),以E.coli HB101为受体菌,以丁草胺、百草敌和草铵膦作为除草剂代表,研究了不同浓度除草剂对可移动质粒... 本研究以同时携带四环素、氨苄青霉素和卡那霉素3种抗生素抗性基因(ARGs)的可移动质粒RP4为供体质粒(保存于供体菌E.coli DH5α中),以E.coli HB101为受体菌,以丁草胺、百草敌和草铵膦作为除草剂代表,研究了不同浓度除草剂对可移动质粒介导的ARGs接合转移的影响,并从细菌细胞膜通透性、胞内ROS含量以及与接合转移相关调控基因的转录水平等角度,阐明了其作用机制.结果表明,100~800mg/L的丁草胺以及40~160mg/L的百草敌都可促进质粒RP4的接合转移.供试浓度范围内,丁草胺皆可刺激细菌胞内产生ROS,百草敌则使ROS水平下降.丁草胺和百草敌处理下,受体菌表面皆出现明显的皱缩,且随着浓度升高,出现孔洞甚至断裂现象.400~800mg/L的丁草胺和40~80mg/L的百草敌皆可通过提高细胞膜通透性,下调kor A基因的转录,同时上调trb Bp、trf Ap和tra A基因的转录,进而促进RP4的接合转移.供试浓度下,草铵膦对RP4的接合影响甚微,对细菌细胞膜通透性、胞内ROS水平以及接合相关调控基因转录水平的影响也不大.研究结果提示需要关注农田环境中除草剂的使用对ARGs传播的风险,并建议通过控制除草剂的种类及施用浓度来控制ARGs在农田生态系统中的接合转移. 展开更多
关键词 除草剂 可移动质粒RP4 抗生素抗性基因 水平迁移 二亲接合
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INCREASED EXPRESSION OF DIRECT GENE TRANSFER INISCHEMIC SKELETAL MUSCLES OF RABBITS 被引量:1
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作者 施娅雪 张柏根 +3 位作者 何天源 陈诗书 江兰英 胡庆沈 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1998年第Z1期5-7,共3页
Objective The gene expression of skeletal muscle under ischemic condition by direct gene injectionwas observed in order to find a new gene delivery method to treat chronic arterial occlusion disease. Methods Weestabli... Objective The gene expression of skeletal muscle under ischemic condition by direct gene injectionwas observed in order to find a new gene delivery method to treat chronic arterial occlusion disease. Methods Weestablished the rabbit hindlimb ischemic model and used plasmid PSV-β-gal as a reporter gene. We transferedgene intramuscularly and detected the activity of β-galactosidase by histochemistry method. Results Weobserved that the gene expression of skeletal muscle under ischemic condition was higher than normalmuscle. Conclusion The result demonstrated that the direct gene injection was suitable for the chronic peripheralarterial occlusion disease, and might be a novel gene delivery method for this disease. 展开更多
关键词 plasmids GENE transfer SKELETAL MUSCLE ISCHEMIA
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Construction and Expression of Recombinant Plasmid pCD-rbFGF in Osteoblasts
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作者 杨操 杨述华 +1 位作者 郭晓东 屈伸 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期109-111,共3页
Summary: To construct basic fibroblast growth factor (bFGF) eukaryotic expression vector and to evaluate the possibility of bFGF gene therapy in orthopedic disease, the pCD-rbFGF recombinant plasmid was constructed by... Summary: To construct basic fibroblast growth factor (bFGF) eukaryotic expression vector and to evaluate the possibility of bFGF gene therapy in orthopedic disease, the pCD-rbFGF recombinant plasmid was constructed by cloning rat basic fibroblast growth factor (bFGF) cDNA into an eukaryotic expression vector, pcDNA 3. Rat osteoblasts were transfected with pCD-rbFGF plasmid by lopofectin mediated gene transfer, the transient expression was detected by streptavidin-biotin-enzyme complex (SABC) method. It was observed that the expression of rat bFGF gene was detected 72 h after transfected distinctly. Basic fibroblast growth factor gene therapy is a method of potential for a wide array of orthopedic diseases. 展开更多
关键词 basic fibroblast growth factor recombinant plasmid gene transfer gene expression
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The Expression of the Plasmid DNA Encoding TGF-β_1 in Endothelium after Injection into the Anterior Chamber
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作者 胡燕华 黄琼 +1 位作者 姜发纲 陈宏 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第4期320-323,共4页
The method of gene transfer into corneal endothelium was investigated to provide a foundation for the study of TGF-β1 gene transfer to inhibit corneal graft rejection.Two days after direct injection of p MAM TGF-β... The method of gene transfer into corneal endothelium was investigated to provide a foundation for the study of TGF-β1 gene transfer to inhibit corneal graft rejection.Two days after direct injection of p MAM TGF-β1 mediated by liposom e into the anterior cham ber of rabbits,one half of corneas were made into paraffin slides and the endothelial layer was carefully torn from the other half to make a single layer slide of endothelia.By means of im munohistochemical technique, the plasmid p MAM TGF- β1 expression product TGF- β1 in the endothelia was detected.Specific TGF- β1 expression was positive in the endothelia on both the paraffin slide and the single layer slide.The results showed that by direct injection into the anterior cham ber,foreign plasmid DNA could be transferred into the endothelia and its expression was obtained.This may provide a foun- dation for further study on TGF-β1 participating in local induction of corneal imm une tolerance. 展开更多
关键词 plasmid TGF- β1 gene transfer im mune tolerance
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CONSTRUCTION AND EXPRESSION OF ADENO-ASSOCIATED VIRUS-BASED PLASMID EXPRESSING VECTORS CONTAINING hIL-2 GENE OR mIFN-γ GENE
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作者 张景迎 梁宏立 陈诗书 《Medical Bulletin of Shanghai Jiaotong University》 CAS 2000年第1期14-17,共4页
Obiective TO improve the plasmid vectors in gene therapy, adeno - associated virus (AAV) basedplasmid expressing vectors containing hIL - 2 gene or mIFN-γ gene were constructed and its expression intransfected cells ... Obiective TO improve the plasmid vectors in gene therapy, adeno - associated virus (AAV) basedplasmid expressing vectors containing hIL - 2 gene or mIFN-γ gene were constructed and its expression intransfected cells was studied. Methods By means of step to step cloning, promoter CMVp was placed at thedownstream of 5’ inverted terminal repeat from AAV (AAV - ITR) of pAP, hIL - 2 gene or mIFN -γ gene insertedinto pAC between CMVp and polyA. Then intron A was inserted into pAC - hIL - 2 or pAC- mIFN-γ betweenCMVp and IL - 2 gene or IFNγ gene to construct pAI- hIL - 2 or pAI- mIFN -γ. Liposome - plasmid complexeswere formed by mixing Dosper with these AAV- based plasmids containing hIL - 2 gene or mIFN- γgene. Results High biotogical activities of IL - 2 or IFN- γ could be detected in the supernatants of NIH3T3 andMM45T Li cells after transfection. Insertion of intron A into pAC- hIL - 2 or pAC- mIFN - γ improved theexpression of IL - 2 or IFN- γ. Conclusion These data demonstrated that the constructed AAV-based plasmidexpressing vectors could ejlciently express therapeutic genes in cultured cells and could be used as a nonviral genetransfer system in human gene therapy. 展开更多
关键词 adeno-associated virus plasmid interleukin-2 interferon-γ gene transfer
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Construction of human VEGF165 gene eukaryotic expression plasmid and its effect on proliferation of vascular endothelial cells 被引量:2
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作者 Organ Grafting Center, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003 , China Department of Cardiothoracic Surgery, the General Hospital of Daqing Oil Field, Daqing 163001 , China and Department of Vascular Surgery, First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第3期364-369,共6页
After organ transplantation, rapid repair of injured vascular endothelial cell (VEC) is a key to prevent graft chronic dysfunction besides control of immunological rejection. Many studies have confirmed that vascular ... After organ transplantation, rapid repair of injured vascular endothelial cell (VEC) is a key to prevent graft chronic dysfunction besides control of immunological rejection. Many studies have confirmed that vascular endothelial growth factor 165 (VEGF165) could accelerate the repair of VEC injury, decrease thrombosis and thrombotic occlusion, and inhibit hyperplasia of the intima. This study was designed to construct eukaryotic expression plasmid pBudCE4.1/VEGF165, and observe its effect on the prolife ration of VEC. METHODS:The VEGF165 gene cloned from human heart tissue by RT-PCR was cloned into eukaryotic expression plasmid pBudCE4.1. The recombinant expression plasmid pBudCE4.1/VEGF165 was identified by restriction enzyme (Hind III and BamH I) digestion analysis, and was sequenced. The pBudCE4.1/VEGF165 was introduced into VEC through lipofection transfection. The VEGF165 mRNA expression by Northern blot and VEGF165 protein expression was detected by immunocytochemical staining. The effect of expression protein on VEC proliferation was detected by flow cytometry. RESULTS:The RT-PCR product of the VEGF165 gene was about 576bp. Sequencing analysis revealed that the sequence of the amplified VEGF165 gene was identical with that in GenBank. Restrictive enzyme digestion analysis showed that recombinant expression plasmid pBudCE4.1/ tVEGF165 had been constructed successfully. The expression of VEGF165 at mRNA and protein levels in the transformed VSMCs had been demonstrated by Northern blot and immunocytochemical staining respectively. The expressed product of VEGF165 could notably accelerate the proliferation of VECs. CONCLUSIONS:pBudCE4.1/VEGF165 is successfully cons- tructed and is expressed in VECs. Expressed VEGF165 can accelerate the VEC proliferation. The present study has laid a foundation for potential use of VEGF165 gene transfection to prevent and treat vascular stenosis in the transplanted organ. 展开更多
关键词 eukaryotic expression plasmid vascular endothelial grow factor 165 vascular endothelial cell gene transfer organ transplantation
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Construction of human eukaryotic expression plasmid vascular endothelial growth factor 165 and its expression in transfected vascular smooth muscles 被引量:5
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作者 Zhong-Jun Wu, Xiao-Hong Yang, Shu-Sen Zheng, Su-Fen Yang and De Shi Organ Transplant Center, First Affiliated Hospital,Zhejiang University School of Medicine, Hangzhou 310003, China Department of General Surgery, Affiliated Hospital of ZunyiMedical College, Zunyi 563003 , China and Department ofVascular Surgery, Chongqing Medical University, Chongqing 400016 , Chi-na 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第3期355-359,共5页
BACKGROUND: The highly specific vascular endothelialgrowth factor (VEGF) induces the growth of vascular en-dothelial cell. This study was to construct the eukaryoticexpression plasmid of vascular endothelial growth fa... BACKGROUND: The highly specific vascular endothelialgrowth factor (VEGF) induces the growth of vascular en-dothelial cell. This study was to construct the eukaryoticexpression plasmid of vascular endothelial growth factorl65(VEGF165) and observe its expression in vascular smoothmuscles (VSMCs).METHODS: The primers were designed and synthesizedaccording to the gene sequences of human VEGF165. TheVEGF165 gene was obtained from umbilic artery tissue bythe method of RT-PCR, then it was cloned to eukaryoticexpression plasmid pBudCE4.1 by recombination strategy.The eukaryotic expression plasmid named pBudCE4.1/VEGF165 was identified by restriction enzyme digestion,and was sequenced. The pBudCE4.1/VEGF165 was trans-fected into VSMCs by using lipofection. The VEGF165 ex-pression of mRNA and protein was detected by RT-PCRand Western blot respectively.RESULTS: VEGF165 was shown about 576bp by RT-PCR.Sequencing revealed the amplified VEGF165 gene was iden-tical with that in the GeneBank. Restrictive enzyme (HindBam HI) digestion analysis showed that recombinantexpression plasmid pBudCE4. l/tVEGF165 had been con-structed successfully. The expression of VEGF165 at mRNAand protein levels in the transformed VSMCs had beendemonstrated by RT-PCR and Western blot.CONCLUSIONS: The recombinant eukaryotic expressionplasmid pBudCE4.1/VEGF165 has been successfully con-structed and expressed in transformed VSMCs. The presentstudy has laid a foundation for VEGF165 gene therapy ofvascular stenosis in the transplant organ. 展开更多
关键词 eukaryotic expression plasmid human vascular endothelial growth factor vascular smooth muscle cell gene transfer organ transplant
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1株产NDM-9和MCR-1的鸡源大肠杆菌的分子及生物学特征 被引量:1
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作者 谢宁 高源 +5 位作者 马藤菲 傅佳妮 谭春娥 吴聪明 沈建忠 汪洋 《中国兽医杂志》 CAS 北大核心 2023年第1期14-19,共6页
为探究质粒介导耐药性的传播特征,本试验以1株分离自山东某肉鸡养殖场的产新德里金属β-内酰胺酶NDM-9和磷酸乙醇胺转移酶MCR-1的大肠杆菌(25R)为研究对象,通过全基因组序列分析、质粒接合转移试验、抗菌药物敏感性试验、大蜡螟毒性感... 为探究质粒介导耐药性的传播特征,本试验以1株分离自山东某肉鸡养殖场的产新德里金属β-内酰胺酶NDM-9和磷酸乙醇胺转移酶MCR-1的大肠杆菌(25R)为研究对象,通过全基因组序列分析、质粒接合转移试验、抗菌药物敏感性试验、大蜡螟毒性感染试验、质粒稳定性试验和生长动力学方法研究其质粒分子和生物学特征。结果显示,携带bla NDM-9和mcr-1的质粒可各自亦可共同转移至其他菌株,并且携带上述耐药基因的质粒对宿主菌造成的适应性代价和毒性较低,更有利于耐药基因的传播。本试验为更深入了解质粒介导的细菌耐药性传播机制提供理论依据。 展开更多
关键词 NDM-9 MCR-1 质粒 接合转移 适应性代价
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抗菌剂对大肠杆菌浓度依赖的联合耐药效应 被引量:1
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作者 童丹青 孙昊宇 +3 位作者 张玉莲 王佳俊 唐量 吴明红 《中国环境科学》 EI CAS CSCD 北大核心 2023年第6期3194-3202,共9页
选择磺胺增效剂(SAPs)、纳米银(AgNPs)以及磺胺(SAs)3类常用抗菌剂,研究了SAPs-AgNPs、SAPs-AgNPs-SAs对大肠杆菌(E.coli)的联合耐药效应,利用突变单位法(MU)和质粒接合转移单位法(CTU)判别了混合抗菌剂在不同浓度下的联合耐药作用模式... 选择磺胺增效剂(SAPs)、纳米银(AgNPs)以及磺胺(SAs)3类常用抗菌剂,研究了SAPs-AgNPs、SAPs-AgNPs-SAs对大肠杆菌(E.coli)的联合耐药效应,利用突变单位法(MU)和质粒接合转移单位法(CTU)判别了混合抗菌剂在不同浓度下的联合耐药作用模式.结果表明,3组SAPs-AgNPs和9组SAPs-AgNPs-SAs表现出浓度依赖的联合耐药效应,即对E.coli突变促进效应的联合作用模式主要表现为拮抗,对E.coli质粒接合转移促进效应的联合作用模式随浓度由拮抗变为协同,推测这与抗菌剂的作用机制有关.较单一抗菌剂,SAPs-AgNPs、SAPs-AgNPs-SAs混合抗菌剂在低浓度时降低了细菌耐药性风险,在高浓度时降低了抗性基因(ARGs)的产生风险但增加了ARGs的传播风险. 展开更多
关键词 混合抗菌剂 浓度依赖 突变 质粒接合转移 联合耐药效应
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非抗生素类新污染物影响质粒携带的抗生素抗性基因(ARGs)水平转移研究进展
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作者 傅欣玥 杨晓波 邱志刚 《生态毒理学报》 CAS CSCD 北大核心 2023年第5期1-12,共12页
人们通常认为抗生素的选择压力是造成抗生素抗性基因快速扩散的原因,但是越来越多的研究表明环境中非抗生素类新污染物也能够造成抗生素抗性基因快速扩散。本文对非抗生素类新污染物影响质粒携带抗性基因水平转移规律和机制研究进展进... 人们通常认为抗生素的选择压力是造成抗生素抗性基因快速扩散的原因,但是越来越多的研究表明环境中非抗生素类新污染物也能够造成抗生素抗性基因快速扩散。本文对非抗生素类新污染物影响质粒携带抗性基因水平转移规律和机制研究进展进行了归纳总结。目前的研究大多集中在内分泌干扰物、药品及个人护理产品以及纳米材料影响R质粒携带抗生素抗性基因水平转移,相关机制主要关注非抗生素类新污染物对活性氧、应激反应以及细胞膜通透性的影响。持久性有机污染物影响质粒携带抗性基因水平转移规律以及非抗生素类新污染物对其他质粒携带的抗生素抗性基因水平转移规律和其他类型的机制可以作为未来的研究方向。 展开更多
关键词 抗生素抗性基因 水平转移 质粒 新污染物
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Ri质粒介导大豆花叶病毒外壳蛋白基因转化大豆的研究 被引量:29
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作者 徐香玲 李兴华 +2 位作者 刘伟华 李集临 王毅 《大豆科学》 CAS CSCD 北大核心 1996年第4期279-288,共10页
本文用含有Ri质粒的发根农杆菌介导,克隆在大肠杆菌JM109中,中间载体质粒PES(具有大豆花叶病毒外壳蛋白基因),通过三亲杂交的方法,将质粒PES导入具Ri质粒的发根农杆菌(pRiA4b)中,用二元载体法转化黑龙江省常见的大豆品种,合丰25,黑农33... 本文用含有Ri质粒的发根农杆菌介导,克隆在大肠杆菌JM109中,中间载体质粒PES(具有大豆花叶病毒外壳蛋白基因),通过三亲杂交的方法,将质粒PES导入具Ri质粒的发根农杆菌(pRiA4b)中,用二元载体法转化黑龙江省常见的大豆品种,合丰25,黑农33等品种.用子叶节,胚轴,幼胚和整株感染转化子菌液,诱导出毛状根,经纸电泳检测有25%左右的毛状根含有冠瘿碱.感染的下胚轴,诱导的毛状根直接形成愈伤组织,从愈伤组织分化出芽,幼胚培养获得不定芽,叶状体和胚状体结构,由器官发生途径产生丛生芽.从下胚轴和子叶节获得丛生芽并再生植株,经纸电泳检测约30%再生植株含有冠瘿碱,PCR和DNA斑点杂交检测均证明大豆花叶病毒外壳蛋白基因,已导入并整合到大豆基因组中. 展开更多
关键词 RI质粒 大豆 转基因植株
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淋球菌耐药性质粒的转移性研究 被引量:10
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作者 张铁军 姜庆五 +1 位作者 张涛 周晓明 《中国皮肤性病学杂志》 CAS 北大核心 2008年第1期23-25,共3页
目的研究淋病奈瑟菌(简称淋球菌)所携带的质粒与耐药性之间的关系。方法对淋球菌耐药株所携带的质粒进行质粒消除实验,并以此消除的质粒转化感受态的大肠杆菌,比较耐药质粒消除和转化前后菌株的耐药性变化情况。结果在亚致死浓度的十二... 目的研究淋病奈瑟菌(简称淋球菌)所携带的质粒与耐药性之间的关系。方法对淋球菌耐药株所携带的质粒进行质粒消除实验,并以此消除的质粒转化感受态的大肠杆菌,比较耐药质粒消除和转化前后菌株的耐药性变化情况。结果在亚致死浓度的十二烷基磺酸钠(SDS)作用下,淋球菌的耐药质粒可以被部分消除(仍然携带42.5kb的质粒)或者完全消除,且消除子在消除前后对抗生素的耐药性发生不同程度的改变;而耐药质粒在不同种属的菌株之间可进行传递,淋球菌的耐药质粒可以传递给感受态的大肠杆菌,筛选出的转化子分别携带含有tetM基因的42.5kb四环素耐药质粒和携带含有TEM-1基因的7.4kb青霉素耐药质粒,转化子可产生对相应抗生素的耐药性。结论淋球菌耐药质粒在介导菌株对抗生素的耐药性起着重要作用,并且可以不同菌株间进行传递。 展开更多
关键词 淋球菌 耐药性 质粒 转化
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鸭源大肠杆菌氨基糖苷类耐药基因的检测与传播扩散机制 被引量:11
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作者 陈燕杰 裴亚玲 +6 位作者 吴华 潘玉善 刘建华 苑丽 杜向党 孟春萍 胡功政 《中国人兽共患病学报》 CAS CSCD 北大核心 2013年第2期138-141,147,共5页
目的探索鸭源大肠杆菌对氨基糖苷类耐药及耐药传播的分子机制。方法用微量稀释法测定鸭源大肠杆菌对氨基糖苷类药物的耐药表型,用PCR和DNA测序方法检测多种氨基糖苷修饰酶基因和质粒介导的16S甲基化酶基因,通过质粒接合试验分析有关耐... 目的探索鸭源大肠杆菌对氨基糖苷类耐药及耐药传播的分子机制。方法用微量稀释法测定鸭源大肠杆菌对氨基糖苷类药物的耐药表型,用PCR和DNA测序方法检测多种氨基糖苷修饰酶基因和质粒介导的16S甲基化酶基因,通过质粒接合试验分析有关耐药基因和耐药性的质粒接合传递特点,并采用基因克隆方法研究rmtB的基因环境。结果 27株分离菌中,有23株、19株、19株和18株分别对安普霉素、庆大霉素、阿米卡星和新霉素耐药,耐药率分别为85.2%、70.4%、70.4%和66.7%。27株中的13株检测到rmtB基因,6株同时检测到rmtB和aac(3)-IV基因。质粒接合试验获得5株接合子,接合子对安普霉素、庆大霉素、阿米卡星和新霉素均高水平耐药(MIC≥128μg/ml),rmtB基因检测呈阳性反应。结论鸭源大肠杆菌氨基糖苷类药物耐药和交叉耐药十分严重,质粒介导的rmtB基因和质粒接合传递是其耐药及其传播扩散的重要机制。 展开更多
关键词 鸭源大肠杆菌 氨基糖苷类耐药基因 质粒接合传递 传播扩散机制
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大黄鱼病原弧菌耐药质粒转移研究 被引量:6
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作者 鄢庆枇 方恩华 +2 位作者 苏永全 王军 庄峙厦 《海洋科学》 CAS CSCD 北大核心 2004年第3期44-49,共6页
用混合培养法进行耐药质粒从大肠杆菌 (Escherichiacoli)向病原弧菌转移研究 ,结果表明 ,耐药质粒 pBR322和 pBR325可以从大肠杆菌向病原弧菌转移。在混合培养30min后 ,部分弧菌获得耐药质粒 ,质粒的转化率随着培养时间的延长而增大 ;... 用混合培养法进行耐药质粒从大肠杆菌 (Escherichiacoli)向病原弧菌转移研究 ,结果表明 ,耐药质粒 pBR322和 pBR325可以从大肠杆菌向病原弧菌转移。在混合培养30min后 ,部分弧菌获得耐药质粒 ,质粒的转化率随着培养时间的延长而增大 ;混合培养24h后 ,转化率分别提高至4.62×10-6~1.18×10-5。耐药质粒 pBR322和 pBR325在2株病原弧菌细胞内能较为稳定地遗传 ,在培养初期 (0~1h) ,均未出现质粒丢失 ,随着培养时间的延长 ,有少量细胞因丢失耐药质粒而表现出对药物的敏感性 ;培养72h后 ,质粒 pBR322和 pBR325在副溶血弧菌(Vibrioparahaemolyticus)中的丢失率分别为10 %和9% ,溶藻弧菌(Vibrioalginolyticus)中2种质粒的丢失率分别为22%和19 %。细菌的药敏试验表明不同菌株在获得耐药质粒后对特定药物的抗性大大增强 ,但不同菌株的耐药水平有所不同 ,说明耐药质粒在不同菌株中的表达水平有所不同。 展开更多
关键词 大黄鱼 病原弧菌 耐药质粒 溶藻弧菌 副溶血弧菌 质粒转移 药物 菌株
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通过原生质体质粒转化提高Streptomyces actuosus诺西肽产量的研究 被引量:3
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作者 李继扬 史训龙 +4 位作者 冯美卿 万睿 文勇 刘晓会 周珮 《工业微生物》 CAS CSCD 北大核心 2008年第5期22-26,共5页
研究利用大肠杆菌-链霉菌穿梭质粒pSE34,构建vhb基因的重组质粒pSEVhb,采用原生质体质粒转化法,将携带vhb的重组质粒转入诺西肽产生菌Streptomyces actuosus中,获得重组菌S.actuosus/pSEVhb。通过CO结合试验,证明VHb在重组菌中成功表达... 研究利用大肠杆菌-链霉菌穿梭质粒pSE34,构建vhb基因的重组质粒pSEVhb,采用原生质体质粒转化法,将携带vhb的重组质粒转入诺西肽产生菌Streptomyces actuosus中,获得重组菌S.actuosus/pSEVhb。通过CO结合试验,证明VHb在重组菌中成功表达。限氧试验表明,重组菌S.ac-tuosus/pSEVhb诺西肽的的产量明显高于出发菌株。传代试验重组菌稳定,适合工业化大生产。 展开更多
关键词 活力链霉菌 STREPTOMYCES actuosus 诺西肽 原生质体质粒转化 Vitrecscilla血红蛋白
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Ri质粒转化番茄的初步研究 被引量:8
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作者 徐香玲 刘伟华 李集临 《生物技术》 CAS CSCD 1993年第1期20-24,共5页
作者利用具Ri质粒的发根农杆菌(Agrobacterium rhizogenes)PRi 15834,PRiA4和PRi2659,对番茄不同品种的不同外植体进行转化试验。在感染部位诱导出毛状根和再生植株,经检测毛状根及再生植株均含有农杆碱和甘露碱。比较不同菌种诱导毛状... 作者利用具Ri质粒的发根农杆菌(Agrobacterium rhizogenes)PRi 15834,PRiA4和PRi2659,对番茄不同品种的不同外植体进行转化试验。在感染部位诱导出毛状根和再生植株,经检测毛状根及再生植株均含有农杆碱和甘露碱。比较不同菌种诱导毛状根的频率和在不同番茄品种间差异。结果表明:发根农杆菌PRi15834和PRiA4感染番茄诱导毛状根的频率比PRi2569诱导频率高。供试番茄品种中强力米寿和粉白砂,感染效果最好。感染方式以叶盘法和胚轴的直接注射法比较适宜。 展开更多
关键词 番茄 RI质粒 转化
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向大豆导入几丁质酶基因的初步研究 被引量:44
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作者 徐香玲 邹联沛 +1 位作者 刘伟华 李集临 《大豆科学》 CAS CSCD 北大核心 1999年第2期101-107,共7页
以根癌农杆菌的Ti质粒为介导,将抗真菌病的几丁质酶基因,导入黑龙江省栽培大豆-东农37号,吉林28号等14个品种。从子叶节和下胚轴诱导出丛生芽,并再生植株,经PCR和DNA分子杂交检测,确认为转化植株。用花粉管通道导... 以根癌农杆菌的Ti质粒为介导,将抗真菌病的几丁质酶基因,导入黑龙江省栽培大豆-东农37号,吉林28号等14个品种。从子叶节和下胚轴诱导出丛生芽,并再生植株,经PCR和DNA分子杂交检测,确认为转化植株。用花粉管通道导入法,直接导入几丁质酶基因,共获223粒种子,经PCR和DNA分子杂交检测的113株大豆幼苗中,有7株呈阳性反应,证明几丁质酶基因已导入并整合到大豆的基因组中。 展开更多
关键词 几丁质酶基因 转基因植株 大豆 基因
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质粒超螺旋比例对其细胞转染效率及表达的影响 被引量:8
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作者 哈小琴 吴祖泽 +2 位作者 张庆林 吴彬 吕同德 《生物技术通讯》 CAS 2005年第4期392-394,共3页
检测质粒开环、闭环比例不同时对其细胞转染效率及表达的影响。构建携带人肝细胞生长因子基因的质粒(pcDNA3-HGF)及携带LacZ报告基因的质粒(pcDNA3-LacZ),用核酸纯化试剂盒提取开环、闭环比例不同的质粒,然后用LipofectAMINE介导它们分... 检测质粒开环、闭环比例不同时对其细胞转染效率及表达的影响。构建携带人肝细胞生长因子基因的质粒(pcDNA3-HGF)及携带LacZ报告基因的质粒(pcDNA3-LacZ),用核酸纯化试剂盒提取开环、闭环比例不同的质粒,然后用LipofectAMINE介导它们分别转染NIH3T3细胞,采用X-Gal染色和ELISA法分别观察转染效率和表达活性。结果表明,用超螺旋比例分别为85.45%和48.44%的质粒pcDNA3-LacZ转染生长旺盛的NIH3T3细胞,48h检测转染效率分别为23.4%±3.8%和9.3%±2.5%,前者约是后者的2.5倍。用超螺旋比例分别为93.28%和40.53%的质粒pcDNA3-HGF转染1×106NIH3T3细胞,ELISA法检测48h细胞培养上清中HGF的表达量分别为46.5±6.3ng和25.6±4.2ng,前者是后者的1.8倍。初步认为质粒开环、闭环比例不同对其细胞转染效率及表达有一定影响,超螺旋比例高时其转染效率及表达量较高。 展开更多
关键词 质粒 超螺旋 转染效率 表达
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