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AMP依赖的酸盐脱酶是一种化酶,在异样酸盐氧化过程中具有化作用

Zhuqing Mao^1,2, Jennifer R Fleming^1,2, Olga Mayans^1,2

¹Department of Biology, University of Konstanz, Constance 78457, Germany.

Proceedings of the National Academy of Sciences of the United States of America

|November 3, 2023

概括

科学家们发现了一种新的酶,AMP依赖的酸盐脱酶 (ApdA),对微生物能量代谢至关重要. 这种酶将酸盐氧化为酸盐,使细菌能够利用这个过程中的能量.

科学领域:

微生物学微生物学
生物化学生物化学
酶学是一种酶学.

背景情况:

酸盐对酸盐的氧化为微生物能量代谢提供电子,这是由于其低氧化还原潜力.
两个厌氧细菌,Desulfotignum phosphitoxidans和Phosphitispora fastidiosa,利用酸盐的氧化产生能量.
负责这种不相似的酸盐氧化过程的关键酶尚未确定.

研究的目的:

为了识别和描述在*D. phosphitoxidans*和*P. fastidiosa*中对酸盐氧化负责的酶.
阐明这种新型酶的机制和生化特性.
了解这种酶在微生物能量代谢中的作用.

主要方法:

来自P. fastidiosa的酶在Escherichia coli中的异质表达.
酶活性测定测量酸盐氧化和NAD+减少.
生物化学表征包括分子质量测定和基质亲和度测量.
序列分析以确定酶与已知的蛋白质家族的相关性.

主要成果:

来自 *P. fastidiosa* 的酶成功表达和表征,显示出对酸盐和NAD+ 的高度亲和力.
酶活性被腺酸酶 (肌动酶) 显著增强,这表明ADP的作用.
序列分析显示该酶是一种AMP依赖的酸盐脱酶 (ApdA),与核酸二酸盐-糖表酶相关.
在*D. phosphitoxidans*中发现了类似的酶,但无法异质表达.

结论:

在这些无氧细菌中,AMP依赖的酸盐脱酶 (ApdA) 是 dissimilatory phosphite oxidation 的关键酶.
ApdA催化了一种不寻常的基质水平酸化反应,通过酸盐氧化将AMP转化为ADP.
这一发现扩大了我们对微生物能量代谢和酶途径多样性的理解.

关键词:

在 ADP 形成的过程中,没有硫的酸氧化物.类植物 (Phosphitispora fastidiosa) 是一种的植物.早期的生物化学进化过程.在基质水平上进行酸化.

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