Proteomic Characterization of Bacillus Subtilis on Bio-degumming of Ramie Bast

ABSTRACT

Ramie bast is a kind of multipurpose biological material. Selective bio-degradation of ramie bast compounds is an important step to partial utilization of complex polysaccharides. Bacillus subtilis is a kind of dominant species with its ability to degrade ramie bast. In order to understand how polysaccharides were catalyzed and utilized in the metabolism of the bacteria, the proteome of B. subtilis strain 168 was analyzed in the presence of ramie bast as sole carbon source, and the cells were grown in glucose as a reference proteome. In total, 2129 proteins are identified, 1871 proteins were used for quantification between different growth conditions, and 363 proteins were differentially expressed under ramie bast and glucose culturing environment. The carbon source affected the abundance of proteins related to carbohydrate transporters via cell membrane, specific reducing sugars degradation pathway, and central carbon metabolism. qRT-PCR analysis revealed that the mRNA levels of four extracellular enzymes participated in polysaccharides degradation were upregulated under ramie bast condition. This study is the first time to uncover comprehensive information on the proteome response of B. subtilis to ramie bast degradation, and may provide important scientific basis for constructing engineering strains in selective extraction of polysaccharide components in ramie bast.

摘要

苎麻韧皮是一种多用途的生物材料. 苎麻韧皮化合物的选择性生物降解是复合多糖部分利用的重要步骤. 枯草芽孢杆菌 (bacillussubtilis) 是苎麻韧皮部降解的优势种. 为了了解多糖在细菌代谢中是如何被催化和利用的, 在以苎麻韧皮为唯一碳源的条件下分析了枯草芽孢杆菌菌株168的蛋白质组, 并将细胞在葡萄糖中生长作为参考蛋白质组. 共鉴定出2129个蛋白质, 1871个蛋白质用于不同生长条件下的定量分析, 363个蛋白质在苎麻韧皮和葡萄糖培养环境下差异表达. 碳源通过细胞膜, 特定还原糖降解途径和中心碳代谢影响碳水化合物转运蛋白的丰度. qRT-PCR分析表明, 在苎麻韧皮条件下, 参与多糖降解的四种胞外酶mRNA水平上调. 本研究首次全面揭示了枯草芽孢杆菌对苎麻韧皮降解的蛋白质组反应, 为构建选择性提取苎麻韧皮多糖组分的工程菌提供了重要的科学依据.

KEYWORDS:

• Ramie bast
• Bacillus subtilis
• polysaccharides metabolism
• catabolic pathway
• label-free quantitative proteomics
• biodegradation

关键词:

• 苎麻韧皮
• 枯草芽孢杆菌
• 多糖代谢
• 分解代谢途径
• 无标记定量蛋白质组学
• 生物降解

Acknowledgments

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: this study was supported by the Natural Science Foundation of Hunan Province (No. 2019JJ50711 and No. 2019JJ40332), the National Natural Science Foundation of China (No. 31871675), China Agriculture Research System (CARS-19-E22), Chinese Agricultural Science and Technology Innovation Project (ASTIP-IBFC08), Central Public-interest Scientific Institution Basal Research Fund (No.1610242021002), and Key Research and Development Program of Changsha (No. kq1901112).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

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