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2-苯乙醇(2-phenylethanol, 2-PE)是一种可食用且有玫瑰香味的高级芳香醇,常用于食品、化妆品和药品行业。由于物理和化学法制备2-PE得率低,不适用于工业生产。而作为单细胞真核微生物的酵母具有高效合成“天然” 2-PE的潜力,因此酵母作为底盘微生物合成2-PE的策略深受研究者青睐。然而,在酵母进行2-PE发酵过程中不免会受到2-PE毒害作用影响。因此,亟须研究酵母耐受2-PE的机制为生产实际提供理论基础,这也有助于选育具有较高2-PE耐受性的酵母菌株。本文综述了酵母2-PE耐受性的研究进展,从酵母2-PE合成途径、2-PE耐受性机理等方面进行阐述,主要说明提升酵母2-PE耐受性的方法。掌握酵母2-PE耐受机制,最终提升酵母2-PE产量及转化效率是今后研究的重中之重。 相似文献
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微生物利用CO2,这不仅提高了自然界碳的利用率,而且能将CO2转化为高附加值产品,可以实现资源的再利用。利用现代生物技术改造微生物以提高CO2的利用效率对生物制造和实现碳中和有一定的促进作用。本文首先总结了微生物利用CO2的6个主要天然途径,并分析这些途径的优缺点,这是对相关途径进行改造的基础;其次提供克服天然途径中碳原子利用率低、能耗高、产品得率低等问题的方法;再次阐述了面向CO2高效利用的合成生物技术研究方向以及途径改造的主要策略和效果;最后展望了微生物利用CO2的机遇及挑战,以期为改造微生物提高CO2利用效率和高附加值产品的生产奠定基础。 相似文献
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代谢工程在芳香化合物生物合成研究中的应用 总被引:4,自引:0,他引:4
生物技术和代谢工程的发展促进了生物合成研究。概述了近年来利用微生物莽草酸途径进行芳香化合物生物合成研究的现况、代谢工程在提高天然芳香化合物产量和扩大合成非天然产生的芳香化合物范围的应用的进展 ,特别是整体代谢工程对提高第二代工程菌产量的作用。指出了生物合成法是生产氨基酸及其它生物小分子如奎尼酸、维生素和抗生素等的未来趋势 ,在工业化生产中有着广阔的应用前景。 相似文献
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萜类生物合成的基因操作 总被引:7,自引:0,他引:7
萜类是一组结构迥异的化合物家族,其中很多具有较大的应用价值,如青蒿素和紫杉醇等,它们在多种微生物和植物中合成,但其天然产量低。萜类代谢工程通过DNA重组技术改造萜类合成细胞中的代谢途径,以提高萜类最终产量或在不含萜类的生物中合成萜类,为促进有用萜类合成提供了新的机会。以萜类化合物生物合成途径的基因转移与表达为切入点,综述了目前在微生物及植物中应用代谢工程提高萜类产量的研究进展。 相似文献
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大肠杆菌中包含体的形成及其活性表达产物的分离 总被引:11,自引:0,他引:11
随着基因工程研究的发展,人们可以利用动物、植物细胞或微生物来合成动物体内某些含量较低、但又有很大药用价值的蛋白分子,如生长激素,白细胞介素-2、尿激酶等等。 在利用微生物进行基因工程的生产中,大肠杆菌(E.coli)是人们常用来做表达目的基因的宿主菌。由这一途径来生产这些天然含量较低的物质,具有产量高,成本低, 相似文献
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麦芽寡糖基海藻糖合成酶(maltosyltrehalose synthase, MTSase)和麦芽寡糖基海藻糖水解酶(maltosyltrehalose hydrolase, MTHase)是酶法合成海藻糖的关键酶。由于该酶系在天然菌种内产量极低,研究者相继在各种模式微生物中对该酶系编码基因进行表达。为了实现MTSase和MTHase在食品安全级菌株的分泌表达,本研究选择重要工业微生物地衣芽孢杆菌(Bacillus licheniformis)作为宿主菌株,以MTSase为报告蛋白,通过对天然启动子进行筛选,发现PP2介导下MTSase的表达量最高,在此基础上利用启动子工程策略构建了一系列串联启动子及合成启动子,发现合成启动子P1-P2在原有PP2基础上将MTSase的表达量提高了37%,该启动子对于MTHase的表达同样具有提高作用,在P1-P2介导下MTHase的表达量较在PP2介导下的提高了10%。在发酵培养基和P1-P2启动子介导下MTSase和MTHase的酶活力分... 相似文献
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为了实现微生物异源合成天然类胡萝卜素玉米黄质,以一株产β-胡萝卜素的酿酒酵母为底盘细胞,利用合成生物学技术构建人工酵母细胞。通过在染色体整合玉米黄质生物合成关键酶-β-胡萝卜素羟化酶(CrtZ),并对其9种来源进行筛选,发现整合欧文氏菌来源的β-胡萝卜素羟化酶的菌株获得玉米黄质的最高产量。法尼基焦磷酸(FPP)作为合成萜烯类天然产物的重要前体,通过敲除 Lpp1和Dpp1 基因,削减法尼基焦磷酸向法呢醇的转化,为玉米黄质的合成提供更多的前体,使玉米黄质的产量提高了1.27倍(从29 mg/L提高到36.8 mg/L)。在此基础上,通过增加欧文氏菌来源CrtZ的基因拷贝数及调节其启动子的强弱来增强β-胡萝卜素羟化酶的表达强度,使得玉米黄质的摇瓶产量达到96.2 mg/L,是目前公开报道中产量最高的。 相似文献
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三萜化合物具有可观的药用价值和经济价值,但是目前的生产过程复杂、产量低,利用微生物异源合成三萜化合物已成为当前研究趋势,大肠杆菌作为常用萜类合成底盘细胞具有异源合成三萜化合物及其前体的天然优势和研究前景。对三萜化合物微生物异源合成研究进展进行了综述,从三萜化合物合成代谢途径、关键酶的特点及大肠杆菌三萜表达模块和底盘细胞适配三个方面对该途径进行了阐述和分析,针对实现大肠杆菌高效合成三萜类化合物所需要解决的基础问题进行讨论,为扩展大肠杆菌作为三萜化合物合成底盘细胞提供建议和前景分析。 相似文献
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2-Phenylethanol (2-PE) is an important aromatic alcohol with a rose-like fragrance. It has been widely applied in the cosmetic, perfume, and food industries and is mainly produced by chemical synthesis. An alternative method for the production of natural flavors and fragrances is the microbial transformation process, which is attracting increasing attention because it is an environmentally friendly process and the products are considered “natural”. The production of 2-PE from L-phenylalanine by biotransformation is possible through the Ehrlich pathway and considerable progress has been made in the development of this process. The present report reviews recent advances in biotechnological production of 2-PE, with emphasis on the strategies used to increase production and the applications of in situ product removal techniques. Future research should focus on product scale-up and product recovery processes for the industrialization of microbial processes. 相似文献
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2-Phenylethanol (2-PE) is an important flavor ingredient with a rose-like odor. Due to concerns about the toxic byproducts potentially found in 2-PE from chemical synthesis, consumers prefer the natural aroma compound, promoting the biosynthesis of 2-PE. Various microorganisms produce 2-PE naturally with low yield. Recent metabolic engineering strategies in yeasts and Escherichia coli have achieved great success in improving 2-PE bioproduction, including the alleviation of feed-back inhibition, improvement of precursor transport, enhancing activities of crucial enzymes, and reduction of by-products. Here, we review the metabolic engineering strategies applied to microorganisms for increasing bioproduction of 2-PE, address current problems, and propose further improvements. 相似文献
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Biotechnological production of 2-phenylethanol 总被引:17,自引:0,他引:17
2-Phenylethanol (2-PE) is an important flavour and fragrance compound with a rose-like odour. Most of the world's annual production of several thousand tons is synthesised by chemical means but, due to increasing demand for natural flavours, alternative production methods are being sought. Harnessing the Ehrlich pathway of yeasts by bioconversion of L-phenylalanine to 2-PE could be an option, but in situ product removal is necessary due to product inhibition. This review describes the microbial production of 2-PE, and also summarizes the chemical syntheses and the market situation. 相似文献
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E. Celińska P. Kubiak W. Białas M. Dziadas W. Grajek 《Journal of industrial microbiology & biotechnology》2013,40(3-4):389-392
This is the first report on the ability of Yarrowia lipolytica strains to produce 2-phenylethanol (2-PE), which has not been identified for this species to date. 2-PE is a valuable aroma compound of rose-like odor. Its isolation from the other than microbial source—rose petals, is limited by the substrate availability. Thus, this chemical compound constitutes an attractive product for biotechnological conversions. To date, the ability to produce 2-PE has been described for such genera as Saccharomyces sp., Kluyveromyces sp., Geotrichum sp., and Pichia sp. This report provides evidence that Y. lipolytica is a novel 2-PE producer. Moreover, the titers of 2-PE obtained in Y. lipolytica NCYC3825 non-optimized cultures, nearly 2 g/l, are competitive to titers obtained by the other species. 相似文献
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Liu J Itagaki Y Ben-Shabat S Nakanishi K Sparrow JR 《The Journal of biological chemistry》2000,275(38):29354-29360
The autofluorescent lipofuscin that accumulates in retinal pigment epithelial cells with age may contribute to an age-related decline in cell function. The major lipofuscin fluorophore, A2E, is a pyridinium bisretinoid. We previously proposed that the biogenesis of A2E involves the following: (i) formation of the Schiff base, N-retinylidene phosphatidylethanolamine from all-trans-retinal and phosphatidylethanolamine in the photoreceptor outer segment membrane; (ii) further reaction of N-retinylidene phosphatidylethanolamine with retinal to yield phosphatidylethanolamine-bisretinoid, A2-PE; (iii) hydrolysis of A2-PE to generate A2E. To provide evidence for this biogenic scheme, all-trans-retinal was reacted with dipalmitoyl-l-alpha-phosphatidylethanolamine to yield DP-A2-PE (A2-PE), as confirmed by UV, with mass spectrometry revealing the molecular ion at m/z 1222.9 (C(77)H(124)O(8)PN) accompanied by product ion at m/z 672.8, representing the phosphoryl-A2E fragment of A2-PE. In reaction mixtures of retinal and outer segments and in samples of Royal College of Surgeons rat retina containing outer segment membranous debris, A2-PE was detected as a series of high performance liquid chromatography peaks, each with UV similar to reference A2-PE. By mass spectrometry, A2-PE consisted of multiple peaks, representing fatty acids with different chain lengths, and the phosphoryl-A2E moiety, m/z 673. Incubation of the retinal/outer segment reaction mixture with phospholipase D generated A2E, as detected by high performance liquid chromatography, thus confirming A2-PE as the A2E precursor. 相似文献