酵母中维生素B6的生物合成:葡萄糖的纳入模式
R N Gupta1, T Hemscheidt, B G Sayer
1Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1.
Journal of the American Chemical Society
|November 15, 2001
概括
酵母中的维生素B6的碳骨架与大肠杆菌的起源不同. 酵母利用一种常见的葡萄糖衍生中间体来合成氧胺和核糖.
科学领域:
- 生物化学 生物化学
- 微生物学 微生物学
- 代谢途径 代谢途径
背景情况:
- 维生素B6 (pyridoxine和pyridoxamine) 对于许多代谢过程至关重要.
- 了解不同生物体中维生素B6的生物合成对于代谢工程和制药应用至关重要.
- 之前的研究确定了Escherichia coli中维生素B6的生物合成途径.
研究的目的:
- 为了阐明维生素B6碳骨架在两个酵母菌种中的起源:Saccharomyces cerevisiae和Candida utilis.
- 为了比较酵母中的维生素B6生物合成途径与之前在大肠杆菌中发现的维生素B6生物合成途径.
主要方法:
- 化Saccharomyces cerevisiae和Candida util与 (13) C标记的D-葡萄糖.
- 从酵母中分离和净化皮里多克萨二化物.
- (13)C核磁共振 ((13) C核磁共振) 谱学以确定 (13)C的纳入模式.
主要成果:
- 来自酵母的皮里多胺二化物中的 (13) C 纳入模式与大肠杆菌中的皮里多的模式显著不同.
- 在酵母中,皮里多胺的C(5) 链表现出类似于cytidine的核糖成分的 (13)C分布.
- 这表明一种常见的葡萄糖衍生的氨酸或氨酸中间体用于酵母中的胺和氨酸合成.
结论:
- 酵母中的维生素B6碳骨架的生物合成途径与大肠杆菌中的生物合成途径大大不同.
- 酵母很可能使用一种常见的粉/粉中介物,它是从葡萄糖中提取的,用于氧胺和 рибо的合成.
- 这一发现为微生物维生素B6生物合成提供了新的见解,并为代谢工程提供了潜在的目标.
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