Journal
FRONTIERS IN MICROBIOLOGY
Volume 12, Issue -, Pages -Publisher
FRONTIERS MEDIA SA
DOI: 10.3389/fmicb.2021.697963
Keywords
nitrogen fixation; Azotobacter chroococcum; posttranslational modifications; lysine succinylation (K-Suc); rhamnolipid
Categories
Funding
- Science and Technology Department of Hunan Province [2018NK1030, 2019GK4018]
- National Key R&D Program of China [2019YFC1604903, 2019YFC1604905]
- National Natural Science Foundation of China [31971042, 21808052]
- State Key Laboratory of Utilization of Woody Oil Resource [2019XK2002]
- China Postdoctoral Science Foundation [2019TQ0088]
- Hunan Provincial Natural Science Foundation of China [2019JJ50227]
- Scientific Research Foundation of Hunan Provincial Education Department [18B090, 18K039]
- Training Program for Excellent Young Innovators of Changsha [kq2009019]
- Double First-Class Construction Project of Hunan Agricultural University [SYL201802002]
Ask authors/readers for more resources
The study showed that rhamnolipid significantly increased the nitrogen fixation activity of Azotobacter chroococcum. Real-time quantitative reverse transcription PCR and global K-Suc profiling revealed that succinylated proteins were involved in oxidative phosphorylation, tricarboxylic acid cycle, and nitrogen metabolism. Multiple succinylation sites on MoFe protein (NifDK) may influence nitrogenase activity, shedding new light on the mechanistic study of nitrogen fixation.
The enhancement of nitrogen fixation activity of diazotrophs is essential for safe crop production. Lysine succinylation (K-Suc) is widely present in eukaryotes and prokaryotes and regulates various biological process. However, knowledge of the extent of K-Suc in nitrogen fixation of Azotobacter chroococcum is scarce. In this study, we found that 250 mg/l of rhamnolipid (RL) significantly increased the nitrogen fixation activity of A. chroococcum by 39%, as compared with the control. Real-time quantitative reverse transcription PCR (qRT-PCR) confirmed that RL could remarkably increase the transcript levels of nifA and nifHDK genes. In addition, a global K-Suc of A. chroococcum was profiled using a 4D label-free quantitative proteomic approach. In total, 5,008 K-Suc sites were identified on 1,376 succinylated proteins. Bioinformatics analysis showed that the addition of RL influence on the K-Suc level, and the succinylated proteins were involved in various metabolic processes, particularly enriched in oxidative phosphorylation, tricarboxylic acid cycle (TCA) cycle, and nitrogen metabolism. Meanwhile, multiple succinylation sites on MoFe protein (NifDK) may influence nitrogenase activity. These results would provide an experimental basis for the regulation of biological nitrogen fixation with K-Suc and shed new light on the mechanistic study of nitrogen fixation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available