Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167, Hannover, Germany.
Departamento de Biomedicina y Biotecnología, Facultad de Farmacia, Universidad de Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
Appl Microbiol Biotechnol. 2018 Feb;102(3):1269-1279. doi: 10.1007/s00253-017-8637-2. Epub 2017 Nov 29.
A type D ferulic acid esterase (FAE) was identified in the culture supernatant of Streptomyces werraensis, purified, sequenced, and heterologously produced in E. coli BL21(DE3)Star by co-expressing chaperones groES-groEL (69 U L). The unique enzyme with a mass of about 48 kDa showed no similarity to other FAEs, and only moderate homology (78.5%) to a Streptomycete β-xylosidase. The purified reSwFAED exhibited a temperature optimum of 40 °C, a pH optimum in the range from pH seven to eight and a clear preference for bulky natural substrates, such as 5-O-trans-feruloyl-L-arabinofuranose (FA) and β-D-xylopyranosyl-(1→2)-5-O-trans-feruloyl-L-arabinofuranose (FAX), compared to the synthetic standard substrate methyl ferulate. Treatment of wheat dough with as little as 0.03 U or 0.3 U kg reSwFAED activity resulted in a significant increase of the bun volume (8.0 or 9.7%, resp.) after baking when combined with polysaccharide-degrading enzymes from Aspergillus. For the first time, the long-standing, but rarely proven positive effect of a FAE in baking was confirmed.
一种类型 D 阿魏酸酯酶（FAE）在绛红链霉菌的培养上清液中被鉴定出来，经过纯化、测序，并通过共表达伴侣蛋白 groES-groEL（69 U L）在大肠杆菌 BL21(DE3)Star 中异源生产。这种独特的酶分子量约为 48 kDa，与其他 FAEs 没有相似性，仅与链霉菌β-木糖苷酶有中等同源性（78.5%）。纯化的 reSwFAED 表现出 40°C 的最适温度、pH7 到 8 之间的最适 pH 值，并且对体积较大的天然底物（如 5-O-反式阿魏酰-L-阿拉伯呋喃糖（FA）和β-D-吡喃木糖基-（1→2）-5-O-反式阿魏酰-L-阿拉伯呋喃糖（FAX））有明显的偏好，与合成标准底物甲基阿魏酸相比。当与来自曲霉的多糖降解酶结合使用时，仅用 0.03 U 或 0.3 U kg 的 reSwFAED 活性处理小麦面团，在烘焙后面包体积就会显著增加（分别为 8.0%或 9.7%）。这是首次证实 FAE 在烘焙中的长期存在但很少被证明的积极作用。
