Henan Provincial Engineering Laboratory of Insect Bio-Reactor and Henan Key Laboratory of Ecological Security for Water Region of Mid-Line of South-To-North, Nanyang Normal University, 1638 Wolong Road, Nanyang, 473061, Henan, People's Republic of China.
College of Physical Education, Nanyang Normal University, Nanyang, 473061, People's Republic of China.
Sci Rep. 2021 Jan 12;11(1):693. doi: 10.1038/s41598-020-80028-3.
Aspergillus niger has the ability to produce a large variety of proteases, which are of particular importance for protein digestion, intracellular protein turnover, cell signaling, flavour development, extracellular matrix remodeling and microbial defense. However, the A. niger degradome (the full repertoire of peptidases encoded by the A. niger genome) available is not accurate and comprehensive. Herein, we have utilized annotations of A. niger proteases in AspGD, JGI, and version 12.2 MEROPS database to compile an index of at least 232 putative proteases that are distributed into the 71 families/subfamilies and 26 clans of the 6 known catalytic classes, which represents ~ 1.64% of the 14,165 putative A. niger protein content. The composition of the A. niger degradome comprises ~ 7.3% aspartic, ~ 2.2% glutamic, ~ 6.0% threonine, ~ 17.7% cysteine, ~ 31.0% serine, and ~ 35.8% metallopeptidases. One hundred and two proteases have been reassigned into the above six classes, while the active sites and/or metal-binding residues of 110 proteases were recharacterized. The probable physiological functions and active site architectures of these peptidases were also investigated. This work provides a more precise overview of the complete degradome of A. niger, which will no doubt constitute a valuable resource and starting point for further experimental studies on the biochemical characterization and physiological roles of these proteases.
黑曲霉具有产生大量蛋白酶的能力，这些蛋白酶对蛋白质消化、细胞内蛋白质周转、细胞信号转导、风味发展、细胞外基质重塑和微生物防御具有特别重要的意义。然而，现有的黑曲霉降解组（黑曲霉基因组编码的全部肽酶谱）并不准确和全面。在此，我们利用 AspGD、JGI 和第 12.2 版 MEROPS 数据库中黑曲霉蛋白酶的注释，编译了一个至少 232 种假定蛋白酶的索引，这些蛋白酶分布在 6 种已知催化类别的 71 个家族/亚家族和 26 个族中，约占 14165 种假定黑曲霉蛋白含量的 1.64%。黑曲霉降解组的组成包括约 7.3%的天冬氨酸、约 2.2%的谷氨酸、约 6.0%的苏氨酸、约 17.7%的半胱氨酸、约 31.0%的丝氨酸和约 35.8%的金属肽酶。102 种蛋白酶已被重新分配到上述 6 个类别中，而 110 种蛋白酶的活性位点和/或金属结合残基被重新表征。还研究了这些肽酶的可能生理功能和活性位点结构。这项工作提供了黑曲霉完整降解组的更精确概述，这无疑将成为进一步研究这些蛋白酶的生化特性和生理作用的宝贵资源和起点。
