人工合成启动子文库研究进展

随着合成生物学的发展,人工合成功能元件在代谢工程领域显示出巨大应用潜力。启动子是调控基因转录水平的重要元件,可以利用人工合成启动子文库对代谢途径进行精细调控,使基因适量表达,实现代谢途径的组合优化。文章综述了人工合成启动子文库的研究进展,评述了不同文库的构建策略,讨论了人工合成启动子文库在代谢工程领域的应用,并展望了人工合成启动子文库的发展方向。     

DREB2s转录因子基因的表达调控机制研究进展

DREB2s是植物特有的转录因子,隶属于AP2/EREBP转录因子家族,对干旱、高盐或低温、高温等非生物胁迫应答基因的表达有重要的调控作用。不同植物来源的DREB2在基因结构上有细微差异,对非生物胁迫的响应亦有不同表现。本文阐述了DREB2s的蛋白质结构特征及其对多种非生物胁迫的应答反应,并深入分析了DREB2s转录水平和转录后加工水平的表达调控分子机制的最新研究进展,为理解DREB2s基因功能、分子调控机制及作物抗逆基因工程提供理论依据。     

Recent progress in consolidated bioprocessing

Consolidated bioprocessing, or CBP, the conversion of lignocellulose into desired products in one step without added enzymes, has been a subject of increased research effort in recent years. In this review, the economic motivation for CBP is addressed, advances and remaining obstacles for CBP organism development are reviewed, and we comment briefly on fundamental aspects. For CBP organism development beginning with microbes that have native ability to utilize insoluble components of cellulosic biomass, key recent advances include the development of genetic systems for several cellulolytic bacteria, engineering a thermophilic bacterium to produce ethanol at commercially attractive yields and titers, and engineering a cellulolytic microbe to produce butanol. For CBP organism development, beginning with microbes that do not have this ability and thus requiring heterologous expression of a saccharolytic enzyme system, high-yield conversion of model cellulosic substrates and heterologous expression of CBH1 and CBH2 in yeast at levels believed to be sufficient for an industrial process have recently been demonstrated. For both strategies, increased emphasis on realizing high performance under industrial conditions is needed. Continued exploration of the underlying fundamentals of microbial cellulose utilization is likely to be useful in order to guide the choice and development of CBP systems.