脯氨酸累积与其合成关键酶活性的关系

The Relationship between the Proline Accumulation and theActivities of te key Enzymes Concerned its Synthetase

假俭草是暖季型的主要成坪草种.5叶期的假俭草幼苗在20%PEG6000(-1.63Mpa)模拟的水分胁迫条件下,脯氨酸作为一种重要的渗透保护物质在24h出现明显增高,而控制脯氨酸合成的谷氨酸途径中的关键酶 1-吡咯啉-5-羧酸合成酶的活性下降,而鸟氨酸途径中的关键酶:δ-鸟氨酸转氨酶的活性却显著增高.S-鸟氨酸转氨酶的活性与脯氨酸的累积有显著的正相关(r=0.96),而 1-吡咯啉-5-羧酸合成酶的活性与脯氨酸的累积呈负相关(r=-0.93).

Eremochloa ophiurodies are the main species of the warm-season turfgrass.The proline content of Eremochloa ophiurodies seedlings of five-leave stage increased rapidly during the 24 hours after treatment by 20%PEG(-1.63Mpa). The activity of 1-pyrroline-5-carboxylate synthetase, a key enzyme of glutamate pathway of proline accumulation, decreased rapidly ; while the activity of ornithine aminotransferase, another key enzyme of ornithine pathway of proline accumulation, increased significantly. The coefficient of correlation between the activity of ornithine aminotransferase and the accumulation of proline was 0.96, but the coefficient of correlation between the acitivity of 1-Pyrroline-5-carboxylate synthetase and the accumulation of proline was -0.93.