Effects of amino acids on the lignocellulose degradation by Aspergillus fumigatus Z5: insights into performance, transcriptional, and proteomic profiles
Effects of amino acids on the lignocellulose degradation by Aspergillus fumigatus Z5: insights into performance, transcriptional, and proteomic profiles
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氨基酸对烟曲霉 Z5 木质纤维素降解的影响：对性能、转录和蛋白质组谱的见解
DOI：
10.1186/s13068-018-1350-2
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发表时间：
2019-01-04
影响因子：
6.3
通讯作者：
Shen, Qirong
中科院分区：
文献类型：
--
作者：
Miao, Jiaxi;Wang, Mengmeng;Shen, Qirong
背景：白念珠菌是一种普遍存在的丝状真菌。在木质纤维素降解中起关键作用，木质纤维素也被定义为有机酸和工业相关酶生产者的重要细胞工厂。然而，各种胞外酶的产生可以受到不同因素的影响，包括氮源、碳源、培养温度和初始pH值。因此，本研究旨在通过转录和蛋白质组学方法揭示氨基酸对烟曲霉Z5木质纤维素降解的影响。用比色法测定添加半胱氨酸、蛋氨酸和硫酸铵的烟曲霉Z5的总毒力。在Cys处理下，内切葡聚糖酶（7.33 ± 0.03 U mL-1）、外切葡聚糖酶（10.50 ± 0.07 U mL-1）、β-葡萄糖苷酶（21.50 ± 0.22 U mL-1）和木聚糖酶（76.43 ± 0.71 U mL-1）均达到峰值。A. LC-MS/MS分析结果表明，Cys、Met和CK（对照，以硫酸铵为唯一氮源）处理下，FumigatusZ 5分别鉴定出227、256和159个差异蛋白。转录组和蛋白质组数据与发酵谱的相关性分析结果表明，大多数纤维素降解酶，包括纤维素酶，半纤维素酶和糖苷水解酶的高度上调时，半胱氨酸添加到生长培养基中。特别是，将纤维素转化为纤维二糖的酶似乎被上调。结论：转录组和蛋白质组分析结果表明，半胱氨酸能显著促进木质纤维素降解菌A.熏蒸Z5.这些结果的可能原因是Z5偏好使用氨基酸如半胱氨酸通过上调碳相关代谢途径来适应外部环境。
Background:As a ubiquitous filamentous fungal,Aspergillusspp. play a critical role in lignocellulose degradation, which was also defined as considerable cell factories for organic acids and industrially relevant enzymes producer. Nevertheless, the production of various extracellular enzymes can be influenced by different factors including nitrogen source, carbon source, cultivation temperature, and initial pH value. Thus, this study aims to reveal how amino acids affect the decomposition of lignocellulose byAspergillus fumigatusZ5 through transcriptional and proteomics methods.Results:The activities of several lignocellulosic enzymes secreted byA. fumigatusZ5 adding with cysteine, methionine, and ammonium sulfate were determined with the chromatometry method. The peak of endo-glucanase (7.33 ± 0.03 U mL-1), exo-glucanase (10.50 ± 0.07 U mL-1), β-glucosidase (21.50 ± 0.22 U mL-1), and xylanase (76.43 ± 0.71 U mL-1) were all obtained in the Cys treatment. The secretomes ofA. fumigatusZ5 under different treatments were also identified by LC-MS/MS, and 227, 256 and 159 different proteins were identified in the treatments of Cys, Met, and CK (Control, treatment with ammonium sulfate as the sole nitrogen source), respectively. Correlation analysis results of transcriptome and proteome data with fermentation profiles showed that most of the cellulose-degrading enzymes including cellulases, hemicellulases and glycoside hydrolases were highly upregulated when cysteine was added to the growth medium. In particular, the enzymes that convert cellulose into cellobiose appear to be upregulated. This study could increase knowledge of lignocellulose bioconversion pathways and fungal genetics.Conclusions:Transcriptome and proteome analyses' results indicated that cysteine could significantly promote the secretion of lignocellulosic enzymes of an efficient lignocellulosic decomposing strain,A. fumigatusZ5. The possible reason for these results is that Z5 preferred to use amino acids such as cysteine to adapt to the external environment through upregulating carbon-related metabolism pathways.