Fig. 1

Promotional effect of inorganic sulfide on the lignocellulolytic response of NJAU4742. A Inorganic sulfide content was only variable for the four treatments: T1: (NH₄)₂SO₄ + 2 KH₂PO₄, T2: 2 × T1; T3: (NH₄)₂HPO₄ + K₂HPO₄, T4: 2 × T3 (see Methods for details). WT of NJAU4742 grown on the straw with different sulfate content at 28 °C for 3 days. B The copies of the NJAU4742 genome were determined by absolute qPCR to characterize hyphae biomass in different treatments. The left Y axis was raw Ct, and the right Y axis was genome copies (biomass). C FPA in different treatments, the strain was grown at 28 °C for 5 days. D Growth status of WT, OE-Tgatps, ∆Tgatps, and RNAi-Tgatps on MM + straw and PDA, strains were grown at 28 °C 4 days. E FoldChange of OE-Tgatps and RNAi Tgatps relative to WT, 21.04 folds up-regulation of Tgatps in OE-Tgatps, 6.76 folds down-regulation in RNAi-Tgatps. F Hyphae biomass of WT, OE-Tgatps, ∆Tgatps and RNAi-Tgatps on straw medium at 28 °C for 5 days. G FPA of WT, OE-Tgatps, ∆Tgatps, and RNAi-Tgatps on MM + straw, strains were grown at 28 °C for 5 days. Bars represent mean ± SEM, with n = 3 biological repeats; red dots resemble values from individual experiments. ANOVA was conducted in (B, C), Tukey's HSD test was used for post hoc comparisons, and the letters “a”, “b”, and “c” were used for significance exhibition. Inorganic sulfide has a significant effect on biomass and FPA (P < 0.05). Student’s t-testing was conducted in (F, G), ***significant difference to WT at two-tailed P = 0.00027 (F, OE-Tgatps), 0.00001 (F, ∆Tgatps), 0.00011 (F, RNAi-Tgatps); *significant difference to WT at two-tailed P = 0.015 (G, OE-Tgatps), ***significant difference to WT at two-tailed P = 0.00001 (G, ∆Tgatps), 0.00022 (G, RNAi-Tgatps)