In the cell walls of grasses ferulic acid is esterified to arabinosyl residues in arabinoxylans that can then undergo oxidative coupling reactions to form ferulate dehydrodimers, trimers and oligomers which function to cross-link cell-wall polysaccharides, limiting cell wall degradability. Fungal ferulic acid esterase can release both esterified monomeric and dimeric ferulic acids from these cell wall arabinoxylans making the cell wall more susceptible to further enzymatic attack and increasing cell wall degradability. Non-embryogenic cell suspension cultures of Festuca arundinacea expressing a Aspergillus niger ferulic acid esterase (faeA) targeted to either the apoplast, or endoplasmic reticulum under the control of a constitutive actin promoter, or to the vacuole under the control of a soybean heat shock promoter, were established and FAE activity determined in the cells and medium during a growth cycle. Analysis of the ester-linked ferulates of the cell walls showed that all three transformed cell lines had both reduced ferulate levels and increased levels of xylanase mediated release of wall phenolics on autodigestion as well as increased rates of cell wall digestion in a simulated rumen environment, when compared to control non-transformed cells.

中文翻译：

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高羊茅 (Festuca arundinacea) 悬浮培养物中真菌阿魏酸酯酶的表达降低了细胞壁阿魏酰化并提高了细胞壁消化率。

在禾本科植物的细胞壁中，阿魏酸被酯化为阿拉伯木聚糖中的阿拉伯糖基残基，然后可以进行氧化偶联反应形成阿魏酸脱氢二聚体、三聚体和寡聚体，它们的作用是交联细胞壁多糖，从而限制细胞壁的降解性。真菌阿魏酸酯酶可以从这些细胞壁阿拉伯木聚糖中释放酯化的单体和二聚阿魏酸，使细胞壁更容易受到进一步的酶攻击并增加细胞壁的降解性。表达黑曲霉阿魏酸酯酶 (faeA) 的黄茅非胚胎细胞悬浮培养物靶向在组成型肌动蛋白启动子控制下的质外体或内质网，或靶向大豆热休克启动子控制下的液泡, 建立并确定生长周期中细胞和培养基中的FAE活性。对细胞壁的酯连接阿魏酸盐的分析表明，所有三种转化细胞系都具有降低的阿魏酸盐水平和增加的木聚糖酶介导的自消化壁酚类释放的水平，以及在模拟瘤胃环境中细胞壁消化率的增加，与对照非转化细胞相比。