金针菇,中国生产最多的食用菌品种,富含赖氨酸。进一步提高其赖氨酸的生物合成对于提高其工业化栽培质量至关重要。柠檬酸诱导显着增加了F.filiformis菌丝的生物量和生长速率,以及赖氨酸含量。在最佳诱导条件下检测赖氨酸生物合成途径中编码酶的基因,揭示了hcs的表达水平,hac,分别是2.67、1.97和1.90倍,分别,相对于控制,而HDH没有发现显著差异,aat,sr,还有shd,aar的表达下降。此外,Ampk的转录水平,发现GCN2、GCN4和TOR显著上调,在最上调的情况下,Ampk,达到比对照高42.68倍的水平,而AMPK的磷酸化上升了近54%。在最佳诱导下的AMPK沉默菌株中,然而,磷酸化增量下降到约16%,赖氨酸含量保持在与WT相同的水平。因此,AMPK被认为是柠檬酸调节丝状菌赖氨酸生物合成的关键中间体。
Flammulina filiformis, the most produced edible mushroom species in China, is rich in lysine. Further enhancing its lysine biosynthesis is vital for improving its quality in industrialized cultivation. Citric acid induction significantly increases both the biomass and growth rate of F. filiformis hyphae, as well as the lysine content. The genes encoding enzymes in the lysine biosynthesis pathway were detected under the optimal induction, revealing that the expression levels of hcs, hac, and hah were 2.67, 1.97, and 1.90 times greater, respectively, relative to the control, whereas no significant difference was seen for hdh, aat, sr, and shd, and the expression of aar decreased. Furthermore, the transcriptional levels of Ampk, GCN2, GCN4, and TOR were found significantly upregulated, with the most upregulated, Ampk, reaching a level 42.68 times greater than that of the control, while the phosphorylation of AMPK rose by nearly 54%. In AMPK-silencing strains under the optimal induction, however, the phosphorylation increment dropped to about 16% and the lysine content remained at the same level as in the WT. Thus, AMPK is presented as the critical intermediary in citric acid\'s regulation of lysine biosynthesis in F. filiformis.