Fang Chunjuan, Chen Xiaoyan
Jiangxi University of Technology, Nanchang, 330098 Jiangxi China.
3 Biotech. 2018 Jul;8(7):302. doi: 10.1007/s13205-018-1314-z. Epub 2018 Jun 29.
The biocontrol function of the repressor of cellulase expression I (ACE1) in was verified through constructing Δ mutant strain by -mediated transformation. The activities of cell wall-degrading enzymes (cellulase, xylanase, chitinase, β-1,3-glucanase, and protease) in the supernatant of Δ mutant strain were distinctly higher than those of control strain, followed with the elevation of related genes transcript levels. Besides, the Δ mutant resulted in an elevating transcript level of , but no obvious change in the expression of , which suggested that ACE1 was negative regulator of the transcription, but not involved in transcription. On core polyketide synthases of four biosynthesis gene clusters for antibiotic secondary metabolites, only the transcription levels of encoding genes Try83179/TryH and Aza79482/AzaJ in Δ mutant strain were significantly higher than that in wild-type during antagonizing with pathogenic fungi and (with the inhibition rate of 30.7 and 19.8%, respectively). The biocontrol function of Δ mutant strain was remarkably enhanced. The results indicated that ACE1, indeed, acted as a repressor for cell wall-degrading enzymes and PKSs expression in , and the Δ mutant strain effectively made related enzymes activities improved with potential enhancement of biocontrol potency.
通过介导转化构建Δ突变株，验证了纤维素酶表达抑制因子I（ACE1）在中的生物防治功能。Δ突变株上清液中细胞壁降解酶（纤维素酶、木聚糖酶、几丁质酶、β-1,3-葡聚糖酶和蛋白酶）的活性明显高于对照菌株，随后相关基因转录水平升高。此外，Δ突变体导致转录水平升高，但表达无明显变化，这表明ACE1是转录的负调控因子，但不参与转录。在抗生素次级代谢产物的四个生物合成基因簇的核心聚酮合酶上，在与致病真菌和拮抗过程中，Δ突变株中编码基因Try83179/TryH和Aza79482/AzaJ的转录水平仅显著高于野生型（抑制率分别为30.7%和19.8%）。Δ突变株的生物防治功能显著增强。结果表明，ACE1确实作为中细胞壁降解酶和聚酮合酶表达的抑制因子，Δ突变株有效地提高了相关酶的活性，并潜在地增强了生物防治能力。
