Londesborough J, Vuorio O E
Research Laboratories, Alko Ltd, Helsinki, Finland.
Eur J Biochem. 1993 Sep 15;216(3):841-8. doi: 10.1111/j.1432-1033.1993.tb18206.x.
A trehalose synthase purified from baker's yeast contained 56-kDa, 102-kDa and 123-kDa polypeptides as its main components. The 102-kDa polypeptide was isolated and shown to be a specific trehalose-6-phosphatase. The trehalose-6-phosphate synthase (Tre6P synthase) activator described by Londesborough and Vuorio [(1991) J. Gen. Microbiol. 137, 323-330] was shown to be phosphoglucoisomerase and to function entirely by generating fructose 6-phosphate. Below 35 degrees C, fructose 6-phosphate is a powerful activator of the Tre6P synthase activity of intact trehalose synthase, especially at physiological phosphate concentration, but does not affect its trehalose-6-phosphatase activity nor the Tre6P synthase activity of truncated trehalose synthase containing truncated versions of the 123-kDa polypeptide. At 50 degrees C, activation by fructose 6-phosphate and inhibition by phosphate are greatly decreased, resulting in an unusually high temperature-dependence for the Tre6P synthase activity at a physiological phosphate concentration (2 mM).
从面包酵母中纯化得到的海藻糖合酶含有56 kDa、102 kDa和123 kDa的多肽作为其主要成分。分离出102 kDa的多肽，证明它是一种特异性的海藻糖-6-磷酸酶。Londesborough和Vuorio（1991年，《普通微生物学杂志》137卷，323 - 330页）所描述的海藻糖-6-磷酸合酶（Tre6P合酶）激活剂被证明是磷酸葡萄糖异构酶，其作用完全是通过生成6-磷酸果糖来实现的。在35℃以下，6-磷酸果糖是完整海藻糖合酶的Tre6P合酶活性的强力激活剂，尤其是在生理磷酸盐浓度下，但不影响其海藻糖-6-磷酸酶活性，也不影响含有截短形式的123 kDa多肽的截短海藻糖合酶的Tre6P合酶活性。在50℃时，6-磷酸果糖的激活作用和磷酸盐的抑制作用大大降低，导致在生理磷酸盐浓度（2 mM）下Tre6P合酶活性具有异常高的温度依赖性。
