Corrêa Camila L, Midorikawa Glaucia E O, Filho Edivaldo Ximenes Ferreira, Noronha Eliane Ferreira, Alves Gabriel S C, Togawa Roberto Coiti, Silva-Junior Orzenil Bonfim, Costa Marcos Mota do Carmo, Grynberg Priscila, Miller Robert N G
Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil.
Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica - PqEB, Brasília, Brazil.
Front Bioeng Biotechnol. 2020 Oct 6;8:564527. doi: 10.3389/fbioe.2020.564527. eCollection 2020.
Given the global abundance of plant biomass residues, potential exists in biorefinery-based applications with lignocellulolytic fungi. Frequently isolated from agricultural cellulosic materials, is a fungus efficient in secretion of commercial enzymes such as cellulases, xylanases and phytases. In the context of biomass saccharification, lignocellulolytic enzyme secretion was analyzed in a strain of following liquid culture with sugarcane bagasse (SB) (1% ) and soybean hulls (SH) (1% ) as sole carbon source, in comparison to glucose (G) (1% ). Analysis of the fungal secretome revealed a maximum of 1.017 UI.mL xylanases after growth in minimal medium with SB, and 1.019 UI.mL after incubation with SH as carbon source. The fungal transcriptome was characterized on SB and SH, with gene expression examined in comparison to equivalent growth on G as carbon source. Over 8000 genes were identified, including numerous encoding enzymes and transcription factors involved in the degradation of the plant cell wall, with significant expression modulation according to carbon source. Eighty-nine carbohydrate-active enzyme (CAZyme)-encoding genes were identified following growth on SB, of which 77 were differentially expressed. These comprised 78% glycoside hydrolases, 8% carbohydrate esterases, 2.5% polysaccharide lyases, and 11.5% auxiliary activities. Analysis of the glycoside hydrolase family revealed significant up-regulation for genes encoding 25 different GH family proteins, with predominance for families GH3, 5, 7, 10, and 43. For SH, from a total of 91 CAZyme-encoding genes, 83 were also significantly up-regulated in comparison to G. These comprised 80% glycoside hydrolases, 7% carbohydrate esterases, 5% polysaccharide lyases, 7% auxiliary activities (AA), and 1% glycosyltransferases. Similarly, within the glycoside hydrolases, significant up-regulation was observed for genes encoding 26 different GH family proteins, with predominance again for families GH3, 5, 10, 31, and 43. is a promising species for production of enzymes involved in the degradation of plant biomass. Given that this fungus is also able to produce thermophilic enzymes, this first global analysis of the transcriptome following cultivation on lignocellulosic carbon sources offers considerable potential for the application of candidate genes in biorefinery applications.
鉴于全球植物生物质残渣储量丰富，基于木质纤维素分解真菌的生物炼制应用具有潜力。[该真菌名称未给出]经常从农业纤维素材料中分离出来，是一种能高效分泌纤维素酶、木聚糖酶和植酸酶等商业酶的真菌。在生物质糖化的背景下，以甘蔗渣（SB）（1%）和大豆壳（SH）（1%）作为唯一碳源，与葡萄糖（G）（1%）相比，对一株[该真菌名称未给出]在液体培养后的木质纤维素分解酶分泌情况进行了分析。对真菌分泌组的分析表明，在以SB为碳源的基本培养基中生长后，木聚糖酶的最高产量为1.017 UI/mL，以SH为碳源培养后为1.019 UI/mL。对该真菌转录组在SB和SH上的特征进行了研究，并与以G为碳源的同等生长条件下的基因表达进行了比较。鉴定出了8000多个基因，包括许多编码参与植物细胞壁降解的酶和转录因子的基因，其表达根据碳源有显著调节。在以SB为碳源生长后，鉴定出89个编码碳水化合物活性酶（CAZyme）的基因，其中77个差异表达。这些基因包括78%的糖苷水解酶、8%的碳水化合物酯酶、2.5%的多糖裂解酶和11.5%的辅助活性酶。对糖苷水解酶家族的分析表明，编码25种不同GH家族蛋白的基因显著上调，其中以GH3、5、7、10和43家族为主。对于SH，在总共91个编码CAZyme的基因中，与G相比，83个也显著上调。这些基因包括80%的糖苷水解酶、7%的碳水化合物酯酶、5%的多糖裂解酶、7%的辅助活性酶（AA）和1%的糖基转移酶。同样，在糖苷水解酶中，编码26种不同GH家族蛋白的基因也显著上调，同样以GH3、5、10、31和43家族为主。[该真菌名称未给出]是生产参与植物生物质降解的酶的有前景的物种。鉴于这种真菌还能够产生嗜热酶，这首次对在木质纤维素碳源上培养后的转录组进行的全面分析为候选基因在生物炼制应用中的应用提供了巨大潜力。
