The crenarchaeon Sulfolobus acidocaldarius has been described to synthesize trehalose via the maltooligosyltrehalose synthase (TreY) and maltooligosyltrehalose trehalohydrolase (TreZ) pathway, and the trehalose glycosyltransferring synthase (TreT) pathway has been predicted. Deletion mutant analysis of strains with single and double deletions of ΔtreY and ΔtreT in S. acidocaldarius revealed that in addition to these two pathways, a third, novel trehalose biosynthesis pathway is operative in vivo: the trehalose-6-phosphate (T6P) synthase/T6P phosphatase (TPS/TPP) pathway. In contrast to known TPS proteins, which belong to the GT20 family, the S. acidocaldarius TPS belongs to the GT4 family, establishing a new function within this group of enzymes. This novel GT4-like TPS was found to be present mainly in the Sulfolobales. The ΔtreY ΔtreT Δtps triple mutant of S. acidocaldarius, which lacks the ability to synthesize trehalose, showed no altered phenotype under standard conditions or heat stress but was unable to grow under salt stress. Accordingly, in the wild-type strain, a significant increase of intracellular trehalose formation was observed under salt stress. Quantitative real-time PCR showed a salt stress-mediated induction of all three trehalose-synthesizing pathways. This demonstrates that in Archaea, trehalose plays an essential role for growth under high-salt conditions.

中文翻译：

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利用一种新型的海藻糖6-磷酸合酶（TPS）/海藻糖6-磷酸磷酸酶（TPP）途径，对Sulfolobus acidocaldarius的盐胁迫响应涉及复杂的海藻糖代谢。

Crnarchaeon Sulfolobus acidocaldarius已被描述为通过麦芽糖基海藻糖合酶（TreY）和麦芽糖基海藻糖海藻糖化酶（TreZ）途径合成海藻糖，并且海藻糖糖基转移合成酶（TreT）途径已经被预测。与Δ的单，双缺失菌株的缺失突变体分析特雷和Δ TRET在S.酸杆菌表明除了这两种途径，第三，新颖海藻糖生物合成途径是可操作的体内：海藻糖-6-磷酸（T6P）合酶/ T6P磷酸酶（TPS / TPP）途径。与属于GT20家族的已知TPS蛋白相反，嗜酸链球菌TPS属于GT4家族，在这组酶中建立了新功能。发现这种新颖的类似于GT4的TPS主要存在于磺基砜中。该Δ特雷Δ TRET Δ TPS的三重突变体S.嗜酸热硫化，其缺乏的能力来合成海藻糖，表明在标准条件或热应力下没有改变的表型，但无法在盐胁迫下生长。因此，在野生型菌株中，在盐胁迫下观察到细胞内海藻糖形成的显着增加。实时定量PCR显示盐胁迫介导的所有三个海藻糖合成途径的诱导。这表明在古细菌中海藻糖在高盐条件下的生长中起着至关重要的作用。