Genetically Controlled Syntheses of New Polymeric Materials

新型高分子材料的基因控制合成

• 批准号: 9510031
• 负责人: David Tirrell
• 金额: $ 75.5万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-09-01 至 1998-11-03
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9510031&HistoricalAwards=false
• 关键词: Genetically; Controlled; Syntheses; New; Polymeric

9510031 Tirrell This project will develop methods for the preparation of architecturally well-defined artificial proteins carrying reactive olefinic, dienyl, acetylenic and pyrrolyl functional groups. A key aspect of the project is the use of artificial genes to direct the synthesis of uniform polymer chains, which will acquire reactive functionality either directly (through the incorporation of unnatural amino acids), or indirectly (through post-translational modification reactions). In either approach, the fidelity of bacterial protein synthesis will be exploited to produce polymeric materials characterized by precise control of chain length, sequence, and stereochemistry. The direct approach will explore the translational activity of six artificial amino acids (and several variants thereof) related to isoleucine, phenylalanine, histidine or tyrosine. There is increasing evidence that the bacterial protein synthesis machinery can utilize a braoder range of amino acids than the twenty that are normally encoded by messenger RNA templates. The amino acid analogues chosen for this study are of particular interest owing to two facts: i). none of the natural amino acids carries olefinic, dienyl, acetylenic or pyrrolyl groups, and ii). such functional groups can be used to endow polymeric materials with interesting and potentially useful chemical and electrochemical properties. The approach to be used for direct incorporation involves: i). synthesis of an artificial gene encoding the sequence of interest, with the natural analogue encoded in place of the target unnatural amino acid, ii). cloning of the artificial gene in an appropriate auxotrophic bacterial strain, and iii). induction of target protein synthesis in a medium containing the unnatural amino acid (and generally depleted of the natural analogue). This strategy has been demonstrated successfully with several unnatural amino acids, including selenomethionine, p-fluorophenylalanine, 3- thienylalanine, trifluoroleucine, azetidinecarboxylic acid, dehydroproline, and thiaproline. Complementary strategy involving post-translational modification will also be explored. In this approach, protein biosynthesis will be used to prepare appropriately designed "base polymers," which will be modified with reagents carrying olefinic, dienyl, acetylenic or pyrrolyl groups. Polymers prepared by either route will be subjected to careful analyses of molecular structure, supramolecular organization, and functional properties. Particular attention will be given to the prospects for creating electrochemically switchable protein films containing pyrrolyl side chains. Such films would be of potential practical use as components of sensors, actuators and controlled delivery devices. %%% This research aims to carry out the synthesis of amino acid polymers with highly controlled structures, through the use of artificial genes. The polymers selected do not occur in nature and will be designed to have interesting electrical and other properties. ***

9510031 Tirrell该项目将开发用于制备携带反应性烯基，二烯基，乙酰基因和吡咯基官能团的建筑定义明确的人造蛋白的方法。 该项目的一个关键方面是使用人工基因来指导均匀的聚合物链的合成，该链将直接获得反应性功能（通过不自然氨基酸的掺入）或间接（通过翻译后修饰反应）。 无论哪种方法，都将利用细菌蛋白质合成的保真度来产生以链长，序列和立体化学的精确控制为特征的聚合物材料。 直接方法将探索与异亮氨酸，苯丙氨酸，组氨酸或酪氨酸有关的六种人造氨基酸（及其几种变体）的翻译活性。 越来越多的证据表明，与通常由Messenger RNA模板编码的二十种相比，细菌蛋白合成机械可以利用氨基酸范围。为这项研究选择的氨基酸类似物特别感兴趣，这是由于两个事实：i）。 天然氨基酸均未携带烯基，二烯基，乙酰基因或吡咯基，以及II）。 此类官能团可用于赋予聚合物材料具有有趣且潜在的化学和电化学特性。 用于直接合并的方法涉及：i）。 编码感兴趣序列的人造基因的合成，自然模拟代替靶标非天然氨基酸，ii）。在适当的营养细菌菌株和iii中的人造基因克隆。 在含有非天然氨基酸的培养基中诱导靶蛋白合成（通常耗尽自然类似物）。 该策略已通过几种非天然氨基酸成功证明，包括硒甲米氨酸，p-氟苯基丙氨酸，3-硫烯基丙氨酸，三氟甲甲基氨基氨酸，氮杂丁二甲基二羧酸，脱氢丙烯和噻种。 还将探讨涉及翻译后修改的互补策略。 在这种方法中，蛋白质的生物合成将用于制备适当设计的“碱基聚合物”，该方法将通过携带烯基，二烯基，乙酰基因或吡咯基的试剂进行修饰。 通过两种途径制备的聚合物将经过分子结构，超分子组织和功能特性的仔细分析。 特别注意创建含有吡咯侧链的电化学可切换蛋白膜的前景。 这样的电影将作为传感器，执行器和受控交付设备的组成部分具有潜在的实际用途。 %% %%这项研究旨在通过使用人工基因来执行具有高度控制结构的氨基酸聚合物的合成。 所选的聚合物在自然界中不会出现，并且设计为具有有趣的电气和其他特性。 ***