Brandt Sophie C, Brognaro Hévila, Ali Arslan, Ellinger Bernhard, Maibach Katharina, Rühl Martin, Wrenger Carsten, Schlüter Hartmut, Schäfer Wilhelm, Betzel Christian, Janssen Stefan, Gand Martin
Faculty of Mathematics, Computer Science and Natural Science, Department of Biology, Biozentrum Klein Flottbek, Molecular Phytopathology, University of Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany.
Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo, CEP, 05508-000, Brazil.
Biotechnol Biofuels. 2021 Mar 20;14(1):74. doi: 10.1186/s13068-021-01927-9.
The transition to a biobased economy involving the depolymerization and fermentation of renewable agro-industrial sources is a challenge that can only be met by achieving the efficient hydrolysis of biomass to monosaccharides. In nature, lignocellulosic biomass is mainly decomposed by fungi. We recently identified six efficient cellulose degraders by screening fungi from Vietnam.
We characterized a high-performance cellulase-producing strain, with an activity of 0.06 U/mg, which was identified as a member of the Fusarium solani species complex linkage 6 (Fusarium metavorans), isolated from mangrove wood (FW16.1, deposited as DSM105788). The genome, representing nine potential chromosomes, was sequenced using PacBio and Illumina technology. In-depth secretome analysis using six different synthetic and artificial cellulose substrates and two agro-industrial waste products identified 500 proteins, including 135 enzymes assigned to five different carbohydrate-active enzyme (CAZyme) classes. The F. metavorans enzyme cocktail was tested for saccharification activity on pre-treated sugarcane bagasse, as well as untreated sugarcane bagasse and maize leaves, where it was complemented with the commercial enzyme mixture Accellerase 1500. In the untreated sugarcane bagasse and maize leaves, initial cell wall degradation was observed in the presence of at least 196 µg/mL of the in-house cocktail. Increasing the dose to 336 µg/mL facilitated the saccharification of untreated sugarcane biomass, but had no further effect on the pre-treated biomass.
Our results show that F. metavorans DSM105788 is a promising alternative pre-treatment for the degradation of agro-industrial lignocellulosic materials. The enzyme cocktail promotes the debranching of biopolymers surrounding the cellulose fibers and releases reduced sugars without process disadvantages or loss of carbohydrates.
向生物基经济转型，涉及可再生农业工业原料的解聚和发酵，这是一项挑战，只有通过实现生物质向单糖的高效水解才能应对。在自然界中，木质纤维素生物质主要由真菌分解。我们最近通过筛选来自越南的真菌，鉴定出六种高效纤维素降解菌。
我们鉴定出一株高产纤维素酶菌株，其活性为0.06 U/mg，该菌株被鉴定为茄病镰刀菌物种复合体连锁6（嗜食镰刀菌）的成员，从红树林木材中分离得到（FW16.1，保藏号为DSM105788）。使用PacBio和Illumina技术对代表九条潜在染色体的基因组进行了测序。使用六种不同的合成和人工纤维素底物以及两种农业工业废料进行深入的分泌蛋白质组分析，鉴定出500种蛋白质，其中包括135种酶，这些酶分属于五种不同的碳水化合物活性酶（CAZyme）类别。对嗜食镰刀菌酶混合物在预处理甘蔗渣、未处理甘蔗渣和玉米叶上的糖化活性进行了测试，并与商业酶混合物Accellerase 1500进行了互补。在未处理的甘蔗渣和玉米叶中，在存在至少196 μg/mL的自制混合物时观察到了初始细胞壁降解。将剂量增加到336 μg/mL促进了未处理甘蔗生物质的糖化，但对预处理生物质没有进一步影响。
我们的结果表明，嗜食镰刀菌DSM105788是用于降解农业工业木质纤维素材料的一种有前景的替代预处理方法。该酶混合物促进纤维素纤维周围生物聚合物的去分支，并释放还原糖，且没有工艺缺点或碳水化合物损失。
