Insights into the response mechanism of Fusarium sp. NF01 during lignite biodegradation using proteomic analysis

Coal biodegradation is promising for sustainable energy development. Studying proteomics in coal biodegra-dation is effective for identifying different proteins and analyzing corresponding biological strategies. However, previous research on this topic is limited. Here, Fusarium sp. NF01 was proven to degrade lignite based on surface morphology, functional groups, and chemical composition for the first time. The proteomics of Fusarium sp. NF01 were then quantitatively and qualitatively analyzed using isobaric tandem mass tags and bioinformatics profiling during lignite biodegradation. The results showed that 1.8 g of lignite was biodegraded into 4.7 mL of black droplets, with microstructural changes. The abundance of 18 proteins, including eight upregulated and ten downregulated proteins (fold change, FC & GE; 1.2 or FC < 0.83 and P-value <0.05), significantly changed during the lignite biodegradation process. These proteins were mainly involved in spermidine synthase, PM H+-ATPase, GGT, 6-HDNO, IPS, and AST. Fusarium sp. NF01 adopted multilevel protein-based strategies, such as nutrient transport and synthesis, positive plasma membrane regulation, immunity optimization, and prevention of cell damage and death to respond to the influence of the lignite environment on its growth and metabolism. These findings provide valuable bioinformation for identifying degradation-specific protein molecules and elucidating the biodegradation mechanism of coal.