PDF(Pubmed)
Abstract：
BACKGROUND: Aspergillus niger ATCC 20611 is an industrially important fructooligosaccharides (FOS) producer since it produces the β-fructofuranosidase with superior transglycosylation activity, which is responsible for the conversion of sucrose to FOS accompanied by the by-product (glucose) generation. This study aims to consume glucose to enhance the content of FOS by heterologously expressing glucose oxidase and peroxidase in engineered A. niger.
RESULTS: Glucose oxidase was successfully expressed and co-localized with β-fructofuranosidase in mycelia. These mycelia were applied to synthesis of FOS, which possessed an increased purity of 60.63% from 52.07%. Furthermore, peroxidase was expressed in A. niger and reached 7.70 U/g, which could remove the potential inhibitor of glucose oxidase to facilitate the FOS synthesis. Finally, the glucose oxidase-expressing strain and the peroxidase-expressing strain were jointly used to synthesize FOS, which content achieved 71.00%.
CONCLUSIONS: This strategy allows for obtaining high-content FOS by the multiple enzymes expressed in the industrial fungus, avoiding additional purification processes used in the production of oligosaccharides. This study not only facilitated the high-purity FOS synthesis, but also demonstrated the potential of A. niger ATCC 20611 as an enzyme-producing cell factory.
RESULTS: Glucose oxidase was successfully expressed and co-localized with β-fructofuranosidase in mycelia. These mycelia were applied to synthesis of FOS, which possessed an increased purity of 60.63% from 52.07%. Furthermore, peroxidase was expressed in A. niger and reached 7.70 U/g, which could remove the potential inhibitor of glucose oxidase to facilitate the FOS synthesis. Finally, the glucose oxidase-expressing strain and the peroxidase-expressing strain were jointly used to synthesize FOS, which content achieved 71.00%.
CONCLUSIONS: This strategy allows for obtaining high-content FOS by the multiple enzymes expressed in the industrial fungus, avoiding additional purification processes used in the production of oligosaccharides. This study not only facilitated the high-purity FOS synthesis, but also demonstrated the potential of A. niger ATCC 20611 as an enzyme-producing cell factory.
摘要：
背景：黑曲霉ATCC20611是工业上重要的低聚果糖（FOS）生产者，因为它产生具有优异转糖基化活性的β-呋喃果糖苷酶，其负责蔗糖向FOS的转化,伴随着副产物(葡萄糖)的产生。本研究旨在通过在工程黑曲霉中异源表达葡萄糖氧化酶和过氧化物酶来消耗葡萄糖以提高FOS的含量。
结果：葡萄糖氧化酶在菌丝体中成功表达并与β-呋喃果糖苷酶共定位。这些菌丝体被应用于FOS的合成，纯度从52.07%提高到60.63%。此外，过氧化物酶在黑曲霉中表达，达到7.70U/g，可以去除葡萄糖氧化酶的潜在抑制剂，促进FOS的合成。最后,葡萄糖氧化酶表达菌株和过氧化物酶表达菌株联合合成FOS，其含量达到71.00%。
结论：该策略允许通过在工业真菌中表达的多种酶获得高含量的FOS，避免在低聚糖的生产中使用额外的纯化过程。本研究不仅促进了高纯度FOS的合成,但也证明了黑曲霉ATCC20611作为产酶细胞工厂的潜力。
结果：葡萄糖氧化酶在菌丝体中成功表达并与β-呋喃果糖苷酶共定位。这些菌丝体被应用于FOS的合成，纯度从52.07%提高到60.63%。此外，过氧化物酶在黑曲霉中表达，达到7.70U/g，可以去除葡萄糖氧化酶的潜在抑制剂，促进FOS的合成。最后,葡萄糖氧化酶表达菌株和过氧化物酶表达菌株联合合成FOS，其含量达到71.00%。
结论：该策略允许通过在工业真菌中表达的多种酶获得高含量的FOS，避免在低聚糖的生产中使用额外的纯化过程。本研究不仅促进了高纯度FOS的合成,但也证明了黑曲霉ATCC20611作为产酶细胞工厂的潜力。
