Department of Plant Pathology and Microbiology, The Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.
FEMS Microbiol Lett. 2010 Apr;305(1):42-8. doi: 10.1111/j.1574-6968.2010.01910.x. Epub 2010 Jan 22.
1-aminocyclopropane-1-carboxylate (ACC) deaminase activity was evaluated in the biocontrol and plant growth-promoting fungus Trichoderma asperellum T203. Fungal cultures grown with ACC as the sole nitrogen source showed high enzymatic activity. The enzyme encoding gene (Tas-acdS) was isolated, and an average 3.5-fold induction of the gene by 3 mM ACC was detected by real-time PCR. Escherichia coli bacteria carrying the intron-free cDNA of Tas-acdS cloned into the vector pAlter-EX1 under the control of the tac promoter revealed specific ACC deaminase (ACCD) activity and the ability to promote canola (Brassica napus) root elongation in pouch assays. RNAi silencing of the ACCD gene in T. asperellum showed decreased ability of the mutants to promote root elongation of canola seedlings. These data suggest a role for ACCD in the plant root growth-promotion effect by T. asperellum.
1-氨基环丙烷-1-羧酸（ACC）脱氨酶活性在生防和促植物生长真菌 Aspergillus terreus T203 中进行了评估。以 ACC 作为唯一氮源生长的真菌培养物表现出高酶活性。该酶编码基因（Tas-acdS）被分离出来，实时 PCR 检测到 3 mM ACC 平均诱导基因表达 3.5 倍。携带 Tas-acdS 无内含子 cDNA 的大肠杆菌在 tac 启动子控制下克隆到载体 pAlter-EX1 中，显示出特异性的 ACC 脱氨酶（ACCD）活性，并能够在袋实验中促进油菜（Brassica napus）根伸长。 Aspergillus terreus 中 ACCD 基因的 RNAi 沉默显示突变体促进油菜幼苗根伸长的能力降低。这些数据表明 ACCD 在 Aspergillus terreus 的植物根生长促进作用中起作用。
