在kutzneride生物合成过程中对threo和erythro-beta-hydroxyglutamic酸的立体特异合成
Matthias Strieker1, Elizabeth M Nolan, Christopher T Walsh
1Department of Chemistry/Biochemistry, Philipps-University, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
Journal of the American Chemical Society
|September 3, 2009
概括
研究人员确定了两种酶,KtzO和KtzP,这些酶在立体特异性地氧化谷氨酸以形成氧谷氨酸异构体. 这些酶与KtzN一起,使抗真菌kutznerides的产生成为可能,为生物组合工程提供了洞察力.
科学领域:
- 生物化学 生物化学
- 自然产品的合成自然产品的合成
- 酶学 是一种酶学.
背景情况:
- 库茨内里德是具有结构多样性的抗真菌六合.
- 它们含有D-3-hydroxyglutamic酸在threo和红色异构体.
- 非核糖体合成酶 (NRPS) 是天然产品生物合成的关键.
研究的目的:
- 为了研究在kutzneride生物合成中负责固态特异性氧化谷氨酸的酶.
- 阐明氧谷氨酸形成和纳入kutznerides的机制.
- 了解KtzO,KtzP和KtzN在NRPS系统内修改谷氨酸中的作用.
主要方法:
- 假定非血型铁氧酶酶KtzO和KtzP的重组表达和体外生化特征.
- 使用谷氨酸作为基质的立体特异性氧化试验.
- 开发一种使用非水解辅酶A类同类物来确定动力参数的方法.
- 对涉及截断的NRPS模块 (KtzH) 和独立的腺化域 (KtzN) 的内转补机制的分析.
主要成果:
- 证实KtzO和KtzP是固态氧化谷氨酸在β位置的酶.
- KtzO产生了threo-L-hydroxyglutamic酸,而KtzP则产生了红色同位素.
- 截断的KtzH的第三模块在功能上通过KtzN,KtzO和KtzP在转化中进行功能补充,用于氧胺酸的生成和结合.
- 确定了KtzO-和KtzP-催化酸化的动力参数.
结论:
- 这项研究详细介绍了立体特异性酸生成的机制,以及通过转基因补充将其纳入kutznerides的机制.
- KtzO和KtzP对于产生特定的氧胺酸异构体至关重要.
- 这些发现为利用这些酶和补充策略在生物组合工程中用于新型天然产品合成提供了基础.
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