在光系统I-O2中,光诱导的H2生成具有I-O2耐受性[FeFe]酶纳米结构
Tristen D Rumbaugh1, Michael J Gorka1, Carol S Baker2
1Department of Chemistry, The Pennsylvania State University, University Park, PA 16802.
概括
我们通过将光系统I (PS I) 与耐氧酶融合而创建了一个新的纳米结构. 该系统有效地从光线中产生燃料,甚至可以在有氧气的情况下运行.
科学领域:
- 生物工程是生物工程.
- 可再生能源可再生能源是可再生能源.
- 光合作用 光合作用
背景情况:
- 化酶和光合作用反应中心 (RCs) 的融合是可持续生物燃料生产的关键策略.
- I型RC可以将电子转移到基酶,以减少质子变成二 (H2).
- 现有的酶系统面临氧气 (O2) 灵敏度和低生产率等局限性.
研究的目的:
- 开发一种耐氧酶-光系统I (PS I) 纳米结构,用于增强的生产.
- 为了研究PsaE,一个PSI子单元,与耐氧[FeFe]酶融合的有效性.
主要方法:
- 使用柔性[GGS]4链接器将PsaE从光系统I (PS I) 融合到耐氧[FeFe]酶 (CbHydA1) 中.
- 在体外合成激活CbHydA1-PsaE仿真体.
- 嵌合体与缺乏PsaE的PSI变体的定量结合.
主要成果:
- 在合成激活时,CbHydA1-PsaE仿真体表现出双向活动.
- 在无氧条件下,纳米构造在84.9 ± 3.1μmol H2 mgchl−1 h−1下产生了H2.
- 在O2的存在下,纳米构造保留了H2生成能力,但以较低的速度 (2.2 ± 0.5 μmol H2 mgchl−1 h−1).
结论:
- 对于开发基于PSI的纳米结构来说,PsaE可以作为一个可行的支架.
- 使用O2耐受性[FeFe]酶使得在存在氧气时能够产生H2.
- 这项研究为在体内产生耐氧氧气的H2系统开辟了可能性.
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