Li Yuanqiu, Lei Lu, Zheng Li, Xiao Ximeng, Tang Hao, Luo Chaobing
Bamboo Diseases and Pests Control and Resources Development Key Laboratory of Sichuan Province, Leshan Normal University, No. 778, Binhe Road, Central District, Leshan, 614000 China.
Biotechnol Biofuels. 2020 Feb 28;13:34. doi: 10.1186/s13068-020-1671-9. eCollection 2020.
Bamboo, a lignocellulosic feedstock, is considered as a potentially excellent raw material and evaluated for lignocellulose degradation and bioethanol production, with a focus on using physical and chemical pre-treatment. However, studies reporting the biodegradation of bamboo lignocellulose using microbes such as bacteria and fungi are scarce.
In the present study, LC1 was isolated from , in which the symbiotic bacteria exhibited lignocellulose degradation ability and cellulase activities. We performed genome sequencing of LC1, which has a 3929,782-bp ring chromosome and 46.5% GC content. The total gene length was 3,502,596 bp using gene prediction, and the GC contents were 47.29% and 40.04% in the gene and intergene regions, respectively. The genome contains 4018 coding DNA sequences, and all have been assigned predicted functions. Carbohydrate-active enzyme annotation identified 136 genes annotated to CAZy families, including GH, GTs, CEs, PLs, AAs and CBMs. Genes involved in lignocellulose degradation were identified. After a 6-day treatment, the bamboo shoot cellulose degradation efficiency reached 39.32%, and the hydrolysate was subjected to ethanol fermentation with and KO11, yielding 7.2 g/L of ethanol at 96 h.
These findings provide an insight for strains in converting lignocellulose into ethanol. LC1, a symbiotic bacteria, can potentially degrade bamboo lignocellulose components and further transformation to ethanol, and expand the bamboo lignocellulosic bioethanol production.
竹子作为一种木质纤维素原料，被认为是一种潜在的优质原材料，并针对木质纤维素降解和生物乙醇生产进行了评估，重点在于采用物理和化学预处理方法。然而，关于利用细菌和真菌等微生物对竹子木质纤维素进行生物降解的研究却很匮乏。
在本研究中，从[具体来源未明确]分离出LC1，其中的共生细菌表现出木质纤维素降解能力和纤维素酶活性。我们对LC1进行了基因组测序，其具有一条3929782 bp的环状染色体，GC含量为46.5%。通过基因预测，总基因长度为3502596 bp，基因区域和基因间隔区域的GC含量分别为47.29%和40.04%。该基因组包含4018个编码DNA序列，且所有序列都已被赋予预测功能。碳水化合物活性酶注释鉴定出136个注释到CAZy家族的基因，包括糖苷水解酶（GH）、糖基转移酶（GTs）、碳水化合物酯酶（CEs）、多糖裂解酶（PLs）、辅助活性酶（AAs）和碳水化合物结合模块（CBMs）。鉴定出了参与木质纤维素降解的基因。经过6天处理后，竹笋纤维素降解效率达到39.32%，水解产物与[具体微生物未明确]和KO11进行乙醇发酵，在96小时时产生了7.2 g/L的乙醇。
这些发现为[具体微生物未明确]菌株将木质纤维素转化为乙醇提供了见解。共生细菌LC1具有潜在降解竹子木质纤维素成分并进一步转化为乙醇的能力，从而扩大了竹子木质纤维素生物乙醇的生产。
