The fungus Thermothielavioides terrestris plays an important role in the global carbon cycle with enzymes capable of degrading polysaccharides from biomass, therefore an attractive source of proteins to be investigated and understood. From cloning to a three-dimensional structure, we foster a deeper characterization of an α-ʟ-arabinofuranosidase, a glycoside hydrolase from the family 62 (TtAbf62), responsible to release arabinofuranose from non-reducing ends of polysaccharides. TtAbf62 was tested with synthetic (pNP-Araf) and polymeric substrates (arabinan and arabinoxylan), showing optimal temperature and pH (for pNP-Araf) of 30 °C and 4.5–5.0, respectively. Kinetic parameters revealed different specific activity for the three substrates, with a higher affinity for pNP-Araf (K_M: 4 ± 1 mM). The hydrolyzing activity of TtAbf62 on sugarcane bagasse suggests high efficiency in the decomposition of arabinoxylan, abundant hemicellulose presented in the sugarcane cell wall. The crystal packing of TtAbf62 reveals an exquisite domain swapping, located at the supramolecular arrangement through a disulfide bond. All crystallographic behaviors go against its monomeric state in solution, indicating a crystal-induced artifact. Structural information will form the basis for further studies aiming the development of optimized enzymatic properties to be used in biotechnological applications.

真菌Thermothielavioides terrestris真菌在全球碳循环中起着重要作用，其酶能够降解生物质中的多糖，因此是研究和理解蛋白质的诱人来源。从克隆到三维结构，我们促进了α-β-阿拉伯呋喃糖苷酶（一种来自62家族（Tt Abf62）的糖苷水解酶）的更深层表征，该酶负责从多糖的非还原末端释放阿拉伯呋喃糖。用合成的（p NP-Ara f）和聚合物底物（阿拉伯聚糖和阿拉伯木聚糖）测试了Tt Abf62 ，显示了最佳的温度和pH（对于p NP-Ara f）分别为30°C和4.5–5.0。动力学参数显示三种底物的比活性不同，对p NP-Ara f的亲和力更高（K _M：4±1 mM）。Tt Abf62在甘蔗渣上的水解活性表明，甘蔗细胞壁中存在的丰富的半纤维素阿拉伯木聚糖的分解效率很高。Tt的晶体包装Abf62揭示了一个精致的域交换，该域通过二硫键位于超分子排列。所有晶体学行为与其在溶液中的单体状态背道而驰，表明晶体诱导的伪像。结构信息将构成进一步研究的基础，这些研究旨在开发用于生物技术应用的最佳酶学性质。