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醌霉素是一类由链霉菌产生的环状寡肽抗生素,结构上拥有一对特征性喹喔啉-2-甲酰基或3-羟基喹啉-2-甲酰基单元.醌霉素选择性插入到DNA分子的碱基对之间,抑制DNA的复制和转录,因而具有良好的肿瘤抑制活性.综述了近十年来醌霉素家族抗生素的生物合成研究进展,通过比较醌霉素不同代表成员的基因簇,归纳这些化合物与其它类型天然产物生物合成以及色氨酸分解代谢中的相似反应,并剖析催化这些反应的酶的功能特性,揭示了醌霉素的化学结构特征和其不同成员之间结构差异的形成原因.在此基础上,还介绍了在异源宿主大肠杆菌中用组合生物合成的方法产生醌霉素类非天然的天然产物的范例,展示了该类抗生素工业化生产的潜力. 相似文献
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生物合成是一个微生物催化反应过程,由有特定功能的微生物催化无毒的、可再生的原材料得到产物。近年来,生物合成在含能材料领域的应用受到了国外含能材料专家的广泛关注。本文将概述生物合成在含能材料中的应用研究进展,包括以木糖和葡萄糖为原材料,由生物合成法得到合成某些含能材料的重要前驱体丁三醇、三醋酸己内酯和间苯三酚等化合物;同时简要介绍了部分含能材料的可能生物合成路径,最后,对生物合成法在含能材料领域的应用前景进行了分析。 相似文献
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由肉桂酸生物合成L-苯丙氨酸 总被引:4,自引:0,他引:4
本文评述了L一苯丙氨酸的各种合成路线、国内外的研究现状及工业化情况,重点讨论了由肉桂酸和氨生物合成L一苯丙氨酸约路线,提出了在国内进一步工作的建议。 相似文献
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The incorporation of (±)-coclaurine, (±)-N-methylcoclaurine, didehydro-N-methylcoclaurinium iodide, (+)-(S)-N-methylcoclaurine and (?)-(R)-N-methylcoclaurine into isotetrandrine in Cocculus laurifolius DC has been studied and specific utilization of (±)-, (+)-(S)- and (?)-R-N-methylcoclaurines and didehydro-N-methylcoclaurinium iodide demonstrated. The evidence supports intermolecular oxidative coupline of (+)-(S)- and (?)-(R)-N-methylcoclaurines to form isotetrandrine. Double labelling experiment with (±)-N- [14C] methyl [1 - 3H] coclaurine demonstrated that the hydrogen atom at the asymmetric centre in N-methylcoclaurine is retained in the bioconversion into isotetrandrine. 相似文献
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Mikrolin (8) and dechloromikrolin (9) have been shown to exist as tautomeric mixtures in solution. The structures of mono-O-trifluoroacetyl Mikrolin (10) and di-O-acetyl Mikrolin (11) have been elucidated. The products 15 to 23 from reduction of the metabolites 8 9 with Pd/C and Zn in aqueous acetic acid have been identified. The 13C-NMR. spectra of Mikrolin (8) and dechloromikrolin (9) and their derivatives have been completely assigned Based on the results of incorporation experiments with sodium [1-13C]-, [2-13C]- and [1, 2-13C]-acetate, a biosynthetic pathway is proposed for Mikrolin (8) . 相似文献
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The incorporation of (±)-, norlaudanosoline, ?nor-reticuline, ?N-methylcoclaurine and ?norlaudanidine into thalicarpine in Cocculus laurifolius DC has been studied and specific utilization of (±)- reticuline is demonstrated. The evidence supports that both the “halves” of thalicapine are derived from reticuline. Parallel feedings of (S)-, and (R)-, reticulines showed that the stereospecifity is maintained in the biosynthesis of thalicarpine from the 1-benzyl-tetrahydroisoquinoline precursor.A double-labelling experiment with (±)-[1-3H, 4′-O14CH3] nor-reticuline has shown that the 4′OMe group of a nor-reticuline unit is lost in the biotransformation into thalicarpine. Feeding experiments also revealed that the plants can convert (S)-bolding and (S)-isoboldine into thalicarpine. 相似文献
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I. Kompi E. Grossmann I. V. Terent'eva G. V. Lazur'evskii 《Chemistry of Natural Compounds》1971,5(1):32-35
Conclusions 1. When DL-[2–14C] tryptophan, sodium [2–14C] pyrotartrate, sodium [14/C]-formate, and universally labeled L-[14C] glutamic acid were introduced through the root system intoCarex brevicollis DC, active brevicolline was obtained.2. Tryptophan and sodium pyrotartrate are precursors of the -carboline moiety of the brevicolline molecule, and sodium formate is a precursor of the N-methyl grouping.3. The introduction of universally labeled L-glutamic acid does not lead to an unambiguous indication of the role of this precursor in the biosynthesis of brevicolline.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 39–43, 1969 相似文献