Expression of bacterial L-aspartate-α-decarboxylase in tobacco increases β-alanine and pantothenate levels and improves thermotolerance
Expression of bacterial L-aspartate-α-decarboxylase in tobacco increases β-alanine and pantothenate levels and improves thermotolerance
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DOI：
10.1007/s11103-005-4844-9
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发表时间：
2006-03-01
影响因子：
5.1
通讯作者：
Rathinasabapathi, B
中科院分区：
文献类型：
--
作者：
Fouad, WM;Rathinasabapathi, B
L-天冬氨酸-α-脱羧酶催化L-天冬氨酸脱羧生成β-丙氨酸和二氧化碳。这是一种不寻常的丙酮酰依赖酶，原核生物特有的，经历有限的自我处理。将编码L-天冬氨酸-α-脱羧酶基因的大肠杆菌pand基因在转基因烟草中进行了结构性启动子表达。通过RNA印迹、免疫印迹和体外酶活性检测证实了转基因的表达。与野生型和媒介对照相比，Pand品系的叶片β-丙氨酸(1.2-4倍)、泛酸(3.2-4.1倍)和总游离氨基酸水平(高达3.7倍)都有所增加。在35℃胁迫1周时，表达L-天冬氨酸-α-脱羧酶纯合子株系的生长受到的影响小于对照株系，在35℃-30℃胁迫3周后，转基因株系的生长显著恢复(P
L-Aspartate-alpha-decarboxylase catalyzes the decarboxylation of L-aspartate to generate beta-alanine and carbon dioxide. This is an unusual pyruvoyl-dependent enzyme unique to prokaryotes that undergoes limited self-processing. The Escherichia coli panD gene encoding L-aspartate-alpha-decarboxylase was expressed under a constitutive promoter in transgenic tobacco. Transgene expression was verified by assays based on RNA blots, immunoblots and enzyme activity in vitro. The panD lines had increased levels of leaf beta-alanine (1.2- to 4-fold), pantothenate (3.2- to 4.1-fold) and total free amino acids (up to 3.7-fold) compared to wild-type and vector controls. Growth of homozygous lines expressing E. coli L-aspartate-alpha-decarboxylase was less affected than that of the control lines when the plants were stressed for 1 week at 35 degrees C. When transferred from 35 to 30 degrees C for 3 weeks, the PanD transgenic lines recovered significantly (P