Institute of Bast Fiber Crops, Chinese Academy of Agriculture Sciences, Changsha, 410000, China.
BMC Genomics. 2020 Feb 3;21(1):121. doi: 10.1186/s12864-020-6531-2.
Microbes play important roles in kanef-degumming. This study aims at identifying the key candidate microbes and proteins responsible for the degumming of kenaf bast (Hibiscus cannabinus). Kenaf bast was cut into pieces and immersed into microbia fermentation liquid collected from different sites. Fermentation liquid samples were collected at 0, 40, 110 and 150 h and then subjected to the 16S/18S rRNA sequencing analysis and isobaric tag for relative and absolute quantitation (iTRAQ) analysis. The microbial (bacterial and fungal) diversity and the differentially expressed proteins/peptides (DEPs) were identified.
With the prolonged degumming time, the weight loss rate increased, the bacterial diversity was decreased. [Weeksellaceae], Enterobacteriaceae and Moraxellaceae were rapidly increased at 040 h, and then decreased and were gradually replaced by Bacteroidaceae from 40 h to 150 h. Similarly, Chryseobacterium and Dysgonomonas were gradually increased at 0110 h and then decreased; Acinetobacter and Lactococcus were increased at 0~40 h, followed by decrease. Bacteroides was the dominant genus at 150 h. Sequencing 18S rRNA-seq showed the gradually decreased Wallemia hederae and increased Codosiga hollandica during degumming. iTRAQ data analysis showed Rds1, and pyruvate kinase I was decreased and increased in the kanef-degumming, respectively. Other DEPs of ferredoxin I, superoxide dismutase and aconitatehydratase were identified to be related to the Glyoxylate and dicarboxylate metabolism (ko00630).
Bacteria including Chryseobacterium, Dysgonomonas, Acinetobacter, Lactococcus and Bacteroidesand fungi like Wallemia hederae and Codosiga hollandica are key candidate microbes for kanef degumming.
微生物在剑麻脱胶中起着重要作用。本研究旨在鉴定负责剑麻脱胶的关键候选微生物和蛋白质。将剑麻切成小块，浸入从不同地点收集的微生物发酵液中。在 0、40、110 和 150 h 时收集发酵液样品，然后进行 16S/18S rRNA 测序分析和等重标记相对和绝对定量 (iTRAQ) 分析。鉴定了微生物（细菌和真菌）多样性和差异表达蛋白/肽（DEP）。
随着脱胶时间的延长，失重率增加，细菌多样性减少。[Weeksellaceae]、肠杆菌科和莫拉西林科在 040 h 迅速增加，然后减少，并在 40150 h 逐渐被拟杆菌科取代。同样，黄单胞菌和 Dysgonomonas 在 0110 h 逐渐增加，然后减少；不动杆菌和乳球菌在 040 h 增加，然后减少。在 150 h 时，拟杆菌是优势属。测序 18S rRNA-seq 显示在脱胶过程中 Wallemia hederae 逐渐减少，Codosiga hollandica 逐渐增加。iTRAQ 数据分析表明，Rds1 和丙酮酸激酶 I 在剑麻脱胶过程中分别减少和增加。其他 DEP，如铁氧还蛋白 I、超氧化物歧化酶和延胡索酸水合酶，被鉴定为与乙醛酸和二羧酸代谢（ko00630）有关。
细菌包括 Chryseobacterium、Dysgonomonas、不动杆菌、乳球菌和拟杆菌，真菌如 Wallemia hederae 和 Codosiga hollandica 是剑麻脱胶的关键候选微生物。
