共 378 篇

Bioconversion of ginsenoside Rc into Rd by a novel α-L-arabinofuranosidase, Abf22-3 from Leuconostoc sp. 22-3: cloning, expression, and enzyme characterization

Antonie van Leeuwenhoek · 2012 · 10.1007/s10482-012-9856-2 · 含路线图 · 有原文

核心问题:如何获得一种高特异性酶,将主要人参皂苷Rc高效转化为稀有人参皂苷Rd,避免非特异性水解。

关键发现:基因abf22-3长1527 bp,编码蛋白预测分子量58,486 Da;最适pH 等 3 条

代谢工程 BiotransformationGinsenoside RcLeuconostocα-L-Arabinofuranosidase Leuconostoc sp. 22-3 Escherichia coli BL21...

Pathway engineering strategies for production of beneficial carotenoids in microbial hosts

Biotechnology Letters · 2012 · 10.1007/s10529-012-0921-8 · 含路线图 · 有原文

核心问题:如何通过代谢工程策略在微生物宿主中高效生产有益类胡萝卜素(如番茄红素、β-胡萝卜素、玉米黄质和虾青素),解决天然提取和化学合成成本高、产量低的问题。

关键发现:采用组合MVA途径的大肠杆菌β-胡萝卜素产量达465 mg/L(MEP途径为390 mg/L) 等 8 条

代谢工程 AstaxanthinCarotenoidLycopeneMetabolic engineeringZeaxanthinβ-Carotene Escherichia coli Escherichia coli Escherichia coli

Key cytomembrane ABC transporters of Saccharomyces cerevisiae fail to improve the tolerance to D-limonene

Biotechnology Letters · 2012 · 10.1007/s10529-012-0931-6 · 含路线图 · 有原文

核心问题:D-柠檬烯对酿酒酵母具有毒性,限制了含柠檬烯柑橘皮废料的生物燃料生产及单萜类化合物的代谢工程改造,需提高酵母对D-柠檬烯的耐受性。

关键发现:85 mg D-柠檬烯/l抑制酿酒酵母生长但不致死,510 mg/l致死 等 3 条

代谢工程 ABC transportersLimoneneMonoterpeneReal-time quantitative PCRStress Saccharomyces cerevis... Saccharomyces cerevis... Saccharomyces cerevis...

Genetic modifications and introduction of heterologous pdc genes in Enterococcus faecalis for its use in production of bioethanol

Biotechnology Letters · 2012 · 10.1007/s10529-012-0964-x · 含路线图 · 有原文

核心问题:如何通过基因改造使 Enterococcus faecalis 具备高效生产生物乙醇的能力,克服乳酸菌天然偏向乳酸发酵的问题。

关键发现:野生型 E. faecalis JH2-2 以葡萄糖为碳源时乙醇产量为 等 7 条

代谢工程 / 发酵工程 Enterococcus faecalisEthanolFermentationLactate dehydrogenasePyruvate decarboxylase Enterococcus faecalis... Enterococcus faecalis... Enterococcus faecalis...

Improved β-carotene biosynthesis and gene transcription in Blakeslea trispora with arachidonic acid

Biotechnology Letters · 2012 · 10.1007/s10529-012-1015-3 · 含路线图 · 有原文

核心问题:如何提高三孢布拉霉(Blakeslea trispora)发酵生产β-胡萝卜素的产量,并阐明花生四烯酸(AA)的调控机制。

关键发现:添加0.4 g/L花生四烯酸并在发酵36 h时加入,β-胡萝卜素产量达690 mg/L,比对照提高73% 等 4 条

发酵工程 Arachidonic acidcarBcarRAhmgRβ-Carotene Blakeslea trispora (A... Blakeslea trispora (A... Blakeslea trispora (A...

Over-expression of stress protein-encoding genes helps Clostridium acetobutylicum to rapidly adapt to butanol stress

Biotechnology Letters · 2012 · 10.1007/s10529-012-0951-2 · 含路线图 · 有原文

核心问题:丁醇对微生物发酵的毒性限制了其产量,需要提高产溶剂梭菌的丁醇耐受性以改善ABE发酵性能。

关键发现:过表达groESL、grpE、htpG均显著提高丁醇耐受性:在2% (v/v)丁醇处理2 h后,存活率分别为45%、25%、56%(野生型和载体对照无法存活);在1% (v/v)丁醇处理6 h后,存活率分别为12%、16%、15%(对照<0.1%)。丁醇产量方面,pT::groESL在MS-M... 等 5 条

代谢工程 Butanol stressGroESLGrpEHeat shock proteinHtpGSolvent tolerance Clostridium acetobuty... Clostridium acetobuty... Clostridium acetobuty...

Increase in the production of β-carotene in recombinant Escherichia coli cultured in a chemically defined medium supplemented with amino acids

Biotechnology Letters · 2012 · 10.1007/s10529-012-1072-7 · 含路线图 · 有原文

核心问题:在重组大肠杆菌中利用化学限定培养基高效生产β-胡萝卜素,解决复合培养基难以达到高细胞浓度和产量不足的问题

关键发现:在补料分批培养中,使用补充氨基酸的化学限定培养基,细胞质量为34 g/l,β-胡萝卜素浓度达2470 mg/l,特定含量为72 mg/g细胞,生产率为77 mg/l·h,分别比复合培养基提高6%、43%、33%和25%。在摇瓶培养中,加入8种最佳氨基酸的化学限定培养基产量为990 mg/l,分...

代谢工程 chemically defined mediumfed-batch culturerecombinant Escherichia coliβ-carotene Escherichia coli DH5α Escherichia coli DH5α Escherichia coli DH5α

Cloning, expression and characterization of meso-2,3-butanediol dehydrogenase from Klebsiella pneumoniae

Biotechnology Letters · 2012 · 10.1007/s10529-012-0933-4 · 含路线图 · 有原文

核心问题:克隆并表征肺炎克雷伯氏菌XJ-Li的meso-2,3-丁二醇脱氢酶,揭示其酶学特性,为其在2,3-丁二醇生物合成及手性化合物合成中的应用提供基础。

关键发现:重组meso-2,3-丁二醇脱氢酶经纯化复性后,还原乙偶姻活性为218 U/mg,氧化meso-2,3-丁二醇活性为66 U/mg 等 4 条

酶工程 2,3-Butanediol dehydrogenaseEnzymatic propertiesExpressionKlebsiella pneumoniaeSubstrate specificity Escherichia coli BL21... Klebsiella pneumoniae...

Molecular cloning and functional expression of two key carotene synthetic genes derived from Blakeslea trispora into E. coli for increased \(\beta\) -carotene production

Biotechnology Letters · 2012 · 10.1007/s10529-012-1004-6 · 含路线图 · 有原文

核心问题:三孢布拉霉中两个关键类胡萝卜素合成基因(ipi和carG)的全长cDNA未知,且其在异源宿主中的功能及对β-胡萝卜素产量提升的作用有待验证。

关键发现:克隆获得ipi(ORF 624 bp,编码207 aa,24.1 kDa)和carG(ORF 963 bp,编码320 aa,36.6 kDa)全长cDNA 等 5 条

代谢工程 Blakeslea trisporaFunctional expressionGeranylgeranyl pyrophosphate synthaseIsopentenyl pyrophosphate isomeraseβ-Carotene Escherichia coli BL21... Escherichia coli BL21...

Biotransformation of ginsenosides Re and Rg1 into ginsenosides Rg2 and Rh1 by recombinant β-glucosidase

Biotechnology Letters · 2012 · 10.1007/s10529-012-0849-z · 含路线图 · 有原文

核心问题:利用重组β-葡萄糖苷酶高效转化主要人参皂苷Re和Rg1为稀有人参皂苷Rg2和Rh1,克服传统酶选择性和产率低的问题。

关键发现:bgp1基因全长为2496 bp,编码831个氨基酸,属于糖苷水解酶家族3 等 5 条

代谢工程 BiotransformationGinsenoside Rg2Ginsenoside Rh1β-Glucosidase Escherichia coli BL21... Escherichia coli BL21...

Improved 2-methyl-1-propanol production in an engineered Bacillus subtilis by constructing inducible pathways

Biotechnology Letters · 2012 · 10.1007/s10529-012-1041-1 · 含路线图 · 有原文

核心问题:高组成型基因表达导致细胞代谢失衡,限制了2-甲基-1-丙醇的产量

关键发现:最佳IPTG诱导时间为9.5 h,最佳诱导剂量为300 μM。在优化条件下,携带诱导途径的菌株BSUAL-03最高产2-甲基-1-丙醇达3.83±0.46 g/L,比组成型途径菌株BSUL04高约60% 等 3 条

代谢工程 2-Methyl-1-propanolBacillus subtilisInducible expressionMetabolic balancePathway engineering Bacillus subtilis Bacillus subtilis Bacillus subtilis

Multiple improvement of astaxanthin biosynthesis in Xanthophyllomyces dendrorhous by a combination of conventional mutagenesis and metabolic pathway engineering

Biotechnology Letters · 2012 · 10.1007/s10529-012-1104-3 · 含路线图 · 有原文

核心问题:野生型Xanthophyllomyces dendrorhous虾青素生物量含量低,难以满足工业生物过程需求,需提高其虾青素积累量。

关键发现:野生型在YPD中总类胡萝卜素164 μg/g干重,虾青素119 μg/g干重 等 5 条

代谢工程 Astaxanthin over-producing mutantsAstaxanthin synthaseCarotenoid pathway engineeringPhytoene synthase Xanthophyllomyces den... Xanthophyllomyces den... Xanthophyllomyces den...

Ectopic expression of a fruit phytoene synthase from Citrus paradisi Macf. promotes abiotic stress tolerance in transgenic tobacco

Molecular Biology Reports · 2012 · 10.1007/s11033-012-1895-2 · 含路线图 · 有原文

核心问题:验证除单子叶PSY3外的其他PSY(如双子叶水果来源的CpPSY)异源表达是否也能通过提高ABA合成来增强植物的非生物胁迫耐受性。

关键发现:转基因烟草在PEG、NaCl和甘露醇胁迫下表现出显著增强的耐受性 等 3 条

代谢工程 Abiotic stressAbscisic acidCarotenoidsDrought toleranceGrapefruit 烟草(Nicotiana tabacum ... 烟草(Nicotiana tabacum ... 烟草(Nicotiana tabacum ...

Characterization and functional analysis of the genes encoding 1-deoxy-D-xylulose-5-phosphate reductoisomerase and 1-deoxy-D-xylulose-5-phosphate synthase, the two enzymes in the MEP pathway, from Amomum villosum Lour

Molecular Biology Reports · 2012 · 10.1007/s11033-012-1676-y · 含路线图 · 有原文

核心问题:从阳春砂(Amomum villosum)中克隆并功能鉴定MEP途径两个关键酶DXR和DXS的编码基因,为通过代谢工程提高其萜类药用成分含量提供基因资源。

关键发现:AvDXR cDNA全长1749 bp,ORF为1416 bp,编码472个氨基酸,预测分子量51.41 kDa,pI 等 3 条

代谢工程 1-deoxy-D-xylulose-5-phosphate reductoisomerase1-deoxy-D-xylulose-5-phosphate synthaseAmomum villosum Lour.Isoprenoid biosynthesisTransgenic tobacco Escherichia coli TOP10 Escherichia coli TOP10 烟草(Nicotiana tabacum ...

Molecular cloning and characterization of three isoprenyl diphosphate synthase genes from alfalfa

Molecular Biology Reports · 2012 · 10.1007/s11033-012-2262-z · 含路线图 · 有原文

核心问题:苜蓿中三萜皂苷等萜类生物合成途径的关键酶——异戊烯基二磷酸合酶(IDS)的分子克隆、功能表征及其调控作用尚不清楚,本研究旨在克隆并鉴定了苜蓿中三个IDS基因(MsFPPS、MsGPPS和MsGGPPS)的功能。

关键发现:克隆得到MsFPPS cDNA全长1368 bp(ORF 1029 bp,编码342个氨基酸,预测蛋白分子量38.98 kDa,pI 等 4 条

代谢工程 AlfalfaEnzyme activityIsoprenyl diphosphate synthasesMethyl jasmonateOverexpressionRecombinant proteins Escherichia coli (BL2... Escherichia coli (BL2... Escherichia coli (BL2...

De novo transcriptome sequencing of Momordica cochinchinensis to identify genes involved in the carotenoid biosynthesis

Plant Molecular Biology · 2012 · 10.1007/s11103-012-9919-9 · 含路线图 · 有原文

核心问题:缺乏杷(Momordica cochinchinensis)的基因组信息,导致无法鉴定其参与类胡萝卜素生物合成的基因

关键发现:获得51,466,670条高质量reads,组装出81,404个unigenes(平均长度388 bp,N50 450 bp) 等 7 条

代谢工程 CarotenoidDigital gene expressionMomordica cochinchinensis SprengNext generation sequencingTranscriptome Momordica cochinchine... Momordica cochinchine... Momordica cochinchine...

Trichome-specific expression of the amorpha-4,11-diene 12-hydroxylase (cyp71av1) gene, encoding a key enzyme of artemisinin biosynthesis in Artemisia annua, as reported by a promoter-GUS fusion

Plant Molecular Biology · 2012 · 10.1007/s11103-012-9986-y · 含路线图 · 有原文

核心问题:解析青蒿素生物合成关键酶CYP71AV1基因启动子的组织特异性表达模式,为通过代谢工程提高青蒿素产量提供分子工具和理论依据。

关键发现:克隆到1,148 bp的cyp71av1启动子(GenBank FJ870128) 等 7 条

代谢工程 Agrobacterium tumefaciensAmorpha-4,11-diene 12-hydroxylaseArtemisia annuaArtemisinin biosynthesisGene regulationPromoter activity Artemisia annua (Chon... Artemisia annua Nicotiana tabacum

Functional characterization of the Gentiana lutea zeaxanthin epoxidase (GIZEP) promoter in transgenic tomato plants

Transgenic Research · 2012 · 10.1007/s11248-012-9591-5 · 含路线图 · 有原文

核心问题:类胡萝卜素生物合成在有色体(chromoplast)与叶绿体组织中的差异调控机制尚不清楚,尤其是调控花瓣和果实中类胡萝卜素积累的启动子元件及进化保守性。

关键发现:在转基因番茄中,GIZEP启动子驱动gusA在含色素的果实和花组织中高表达,而在叶、茎、根等含叶绿体组织中几乎不表达。成熟绿果中GUS活性较低,至橙果期GUS活性增加5倍 等 2 条

代谢工程 CarotenoidChromoplastGentiana luteaPromoterTransgenic tomatoZeaxanthin epoxidase 番茄(Solanum lycopersic... 番茄(Solanum lycopersic... 番茄(Solanum lycopersic...

Glutathione reductase from Brassica rapa affects tolerance and the redox state but not fermentation ability in response to oxidative stress in genetically modified Saccharomyces cerevisiae

World Journal of Microbiology and Biotechnology · 2012 · 10.1007/s11274-011-0988-8 · 含路线图 · 有原文

核心问题:外源表达植物来源的谷胱甘肽还原酶(BrGR)能否减轻酿酒酵母在氧化胁迫(如H2O2)下的有害效应,并增强其胁迫耐受性。

关键发现:转基因酵母(TG)的总GR活性比野生型(WT)高2倍 等 6 条

代谢工程 BrGR expressionCell rescue proteinsOxidative stressRedox stateStress tolerance Saccharomyces cerevis... Saccharomyces cerevis... Saccharomyces cerevis...

Screening and characteristics of a butanol-tolerant strain and butanol production from enzymatic hydrolysate of NaOH-pretreated corn stover

World Journal of Microbiology and Biotechnology · 2012 · 10.1007/s11274-012-1107-1 · 含路线图 · 有原文

核心问题:丁醇对产溶剂梭菌的毒性抑制导致溶剂产量和底物浓度受限,以及木质纤维素水解液中的抑制物影响ABE发酵效率

关键发现:突变株206在60g/L葡萄糖下溶剂产量比野生型高50% 等 7 条

发酵工程 ABE fermentationButanol resistanceClostridium acetobutylicumCorn stoverNTG mutationUndetoxified hydrolysate Clostridium acetobuty...