Morphology engineering of Aspergillus oryzae for l-malate production
Morphology engineering of Aspergillus oryzae for l-malate production
复制标题
用于 L-苹果酸生产的米曲霉形态工程
DOI：
10.1002/bit.27089
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发表时间：
2019-07-09
影响因子：
3.8
通讯作者：
Liu, Liming
中科院分区：
文献类型：
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作者：
Chen, Xiulai;Zhou, Jie;Liu, Liming
米曲霉是一种具有竞争力的天然有机酸生产菌，但其生产能力与特定的形态类型密切相关。在此基础上，利用形态工程技术对米曲霉进行形态调整，提高L-苹果酸的产量。首次对米曲霉形态与L-苹果酸发酵的相关性进行了研究，确定了L-苹果酸生产单位体积发酵液中颗粒总体积(V值)为120~130 mm(3)/ml的最佳范围，通过控制搅拌速度、通气量等操作参数的变化，通过优化酪氨酸蛋白磷酸酶(CDC14)、后期促进复合体/环状激活蛋白(CDC20)和细胞分裂控制蛋白45(CDC45)等细胞分裂周期蛋白的表达，改善了米曲霉的形态。将CDC14的强度控制在中等水平，V值落在V值的最佳范围内，最终得到的工程菌CDC14(3)在30-L发酵罐中的产量达到142.5 g/L L-苹果酸。这一战略为今后L-苹果酸的工业化生产奠定了良好的基础，并为发展丝状真菌作为细胞工厂生产其他化学品打开了窗口。
Aspergillus oryzae is a competitive natural producer for organic acids, but its production capacity is closely correlated with a specific morphological type. Here, morphology engineering was used for tailoring A. oryzae morphology to enhance l-malate production. Specifically, correlation between A. oryzae morphology and l-malate fermentation was first conducted, and the optimal range of the total volume of pellets in a unit volume of fermentation broth (V value) for l-malate production was 120-130 mm(3)/ml. To achieve this range, A. oryzae morphology was improved by controlling the variation of operational parameters, such as agitation speed and aeration rate, and engineered by optimizing the expression of cell division cycle proteins such as tyrosine-protein phosphatase (CDC14), anaphase promoting complex/cyclosome activator protein (CDC20), and cell division control protein 45 (CDC45). By controlling the strength of CDC14 at a medium level, V value fell into the optimal range of V value and the final engineered strain A. oryzae CDC14(3) produced up to 142.5 g/L l-malate in a 30-L fermenter. This strategy described here lays a good foundation for industrial production of l-malate in the future, and opens a window to develop filamentous fungi as cell factories for production of other chemicals.