在人体新陈代谢中,C11orf54催化L-烯酸的形成
Marco Malatesta1, Carlo De Rito1, Francesca Gasparini1
1Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma 43124, Italy.
概括
研究人员确定了负责形成L-硫酶的酶,这是松尿症的关键标志物. 这一发现完成了糖路径,揭示了能量代谢和维生素C生物合成之间的进化权衡.
科学领域:
- 生物化学 生物化学
- 代谢途径 代谢途径
- 进化生物学 进化生物学
背景情况:
- 尿症的特征是L-基分泌,但其分子基础尚不清楚.
- 负责L-硫酶形成的酶尚未确定,这使得对粉酶途径的理解存在差距.
研究的目的:
- 为了识别催化L-烯酸形成的基因和酶.
- 为了阐明完整的位路径及其进化历史.
主要方法:
- 在1,929个真核生物基因组中对511,114个正确组进行同进化分析.
- 将基因组数据投射到代谢地图上,以识别未绘制的基因.
- 在C11orf54.4的DUF1907域的生物化学表征.
主要成果:
- C11orf54的DUF1907域被确定为β-基托-L-酸 (BKG) 脱碳酶.
- 这种酶通过BKG与协调的迈凯利斯复合物催化L-糖的形成.
- 建立了完整的粉酶路径,从黑色素前体中产生粉酶糖.
- 这一途径在双胞胎体中保存,与L-酸生物合成途径形成鲜明对比.
结论:
- 鉴定BKG脱碳酶完成了粉酶路径.
- 糖通路的存在表明,在某些物种中,一种进化权衡有利于能量代谢而不是L-酸生物合成.
- 这种权衡对于具有足够饮食维生素C摄入量的生物来说是相关的.
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