PDF(Pubmed)
Abstract：
Alanine transaminase (ALT) is an important amino acid-metabolizing enzyme in silkworm Bombyx mori L., and is mainly involved in transferring glutamate to alanine (serving as an essential precursor in silk protein synthesis) through transamination. Therefore, it is generally believed that silk protein synthesis in the silk gland and the cocoon quantity increase with the increase in ALT activity to a certain extent. Here, a novel analytical method was developed to determine the ALT activity in several key tissues of Bombyx mori L. including the posterior silk gland, midgut, fat body, middle silk gland, trachea and hemolymph, by combining the direct-analysis-in-real-time (DART) ion source with a triple-quadrupole mass spectrometer. In addition, a traditional ALT activity assay, the Reitman-Frankel method, was also used to measure ALT activity for comparison. The ALT activity results obtained via the DART-MS method are in good agreement with those obtained via the Reitman-Frankel method. However, the present DART-MS method provides a more convenient, rapid and environmentally friendly quantitative method for ALT measurement. Especially, this method can also monitor ALT activity in different tissues of Bombyx mori L. in real time.
摘要：
丙氨酸转氨酶(ALT)是家蚕重要的氨基酸代谢酶,并且主要涉及通过氨基转移将谷氨酸转移到丙氨酸（在丝蛋白合成中作为必需前体）。因此,一般认为,在一定程度上,随着ALT活性的增加,丝腺和茧内丝蛋白合成量增加。这里,开发了一种新的分析方法来确定BombyxmoriL.的几个关键组织中的ALT活性，包括后丝腺，中肠,脂肪的身体，中间丝腺，气管和血淋巴,通过将直接分析实时（DART）离子源与三重四极杆质谱仪相结合。此外,传统的ALT活性测定，Reitman-Frankel方法,还用于测量ALT活性以进行比较。通过DART-MS方法获得的ALT活性结果与通过Reitman-Frankel方法获得的结果非常吻合。然而,目前的DART-MS方法提供了一种更方便的，用于ALT测量的快速和环境友好的定量方法。尤其是,该方法还可以实时监测家蚕不同组织的ALT活性。
