By combining two enzymes, formate dehydrogenase (FateDH) and formaldehyde dehydrogenase (FaldDH), it is possible to drive the thermodynamically unfavorable conversion of CO₂ to formaldehyde. For this purpose, the enzymes were coimmobilized in siliceous mesostructured cellular foams (MCFs). A high degree of adsorption of both enzymes was achieved by coimmobilizing the enzymes sequentially, i.e., first FateDH and then FaldDH. The highest conversion rate was obtained with an enzyme mass ratio of 1:15 (FateDH/FaldDH). Using MCF functionalized with mercaptopropyl groups (MCF-MP), the activity increased ∼4 times compared to the enzymes free in solution. To probe the distance between the two enzymes, they were separately labeled with either Cy3 or Cy5 dyes and studied with Förster resonance energy transfer (FRET). An increased energy transfer was observed when the enzymes were coimmobilized in MCF-MP, suggesting that the two enzymes are in close proximity, resulting in higher conversion of CO₂ to formaldehyde.

中文翻译：

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Förster共振能量转移研究通过共固定酶在硅质介孔泡沫中改善了CO ₂到甲醛的生物催化转化。

通过结合甲酸脱氢酶（FateDH）和甲醛脱氢酶（FaldDH）这两种酶，可能会导致热力学上不利的CO ₂转化去甲醛。为此目的，将酶共固定在硅质介孔泡沫（MCFs）中。通过顺序固定酶，即先固定FateDH，再固定FaldDH，可以实现两种酶的高度吸附。以1:15的酶质量比（FateDH / FaldDH）获得最高的转化率。使用带有巯基丙基官能团的MCF（MCF-MP），与溶液中游离的酶相比，其活性提高了约4倍。为了探测两种酶之间的距离，分别用Cy3或Cy5染料标记了它们，并用Förster共振能量转移（FRET）进行了研究。当这些酶共固定在MCF-MP中时，观察到能量转移增加，表明这两种酶非常接近，从而导致更高的CO ₂转化率 去甲醛。