Institute of Biochemistry, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany.
Appl Microbiol Biotechnol. 2021 May;105(10):4111-4126. doi: 10.1007/s00253-021-11337-4. Epub 2021 May 17.
Aryl-alcohol oxidases (AAOs) are FAD-containing enzymes that oxidize a broad range of aromatic as well as aliphatic allylic alcohols to aldehydes. Their broad substrate spectrum accompanied by the only need for molecular oxygen as cosubstrate and production of hydrogen peroxide as sole by-product makes these enzymes very promising biocatalysts. AAOs were used in the synthesis of flavors, fragrances, and other high-value-added compounds and building blocks as well as in dye decolorization and pulp biobleaching. Furthermore, AAOs offer a huge potential as efficient suppliers of hydrogen peroxide for peroxidase- and peroxygenase-catalyzed reactions. A prerequisite for application as biocatalysts at larger scale is the production of AAOs in sufficient amounts. Heterologous expression of these predominantly fungal enzymes is, however, quite challenging. This review summarizes different approaches aiming at enhancing heterologous expression of AAOs and gives an update on substrates accepted by these promising enzymes as well as potential fields of their application. KEY POINTS: • Aryl-alcohol oxidases (AAOs) supply ligninolytic peroxidases with HO. • AAOs accept a broad spectrum of aromatic and aliphatic allylic alcohols. • AAOs are potential biocatalysts for the production of high-value-added bio-based chemicals.
芳基醇氧化酶（AAOs）是一类含有黄素腺嘌呤二核苷酸（FAD）的酶，能够氧化广泛的芳香族和脂肪族烯丙醇为醛。它们广泛的底物谱，仅需要分子氧作为辅助底物，并且只产生过氧化氢作为唯一的副产物，这使得这些酶成为非常有前途的生物催化剂。AAOs 已被用于合成香料、香精和其他高附加值的化合物和构建模块，以及用于染料脱色和纸浆生物漂白。此外，AAOs 作为过氧化物酶和过氧酶催化反应中过氧化氢的有效供应源，具有巨大的潜力。作为生物催化剂在更大规模上应用的前提是能够以足够的量生产 AAOs。然而，这些主要来自真菌的酶的异源表达颇具挑战性。本文综述了旨在增强 AAOs 异源表达的不同方法，并更新了这些有前途的酶所接受的底物以及它们的潜在应用领域。关键点： • 芳基醇氧化酶（AAOs）为木质素过氧化物酶提供 HO。 • AAOs 接受广泛的芳香族和脂肪族烯丙醇。 • AAOs 是生产高附加值生物基化学品的潜在生物催化剂。
