Improving isobutanol titers in Saccharomyces cerevisiae with over-expressing NADPH-specific glucose-6-phosphate dehydrogenase (Zwf1)
Improving isobutanol titers in Saccharomyces cerevisiae with over-expressing NADPH-specific glucose-6-phosphate dehydrogenase (Zwf1)
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DOI：
10.1007/s13213-017-1304-0
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发表时间：
2017-12-01
影响因子：
3
通讯作者：
Zhang, Aili
中科院分区：
文献类型：
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作者：
Feng, Ruiqi;Li, Jingzhi;Zhang, Aili
异丁醇是一种比乙醇更有前途的生物燃料，因为它具有更高的能量密度和更低的吸湿性。酿酒酵母作为一种模式真核生物，对高级醇具有较强的耐受性，具有生产异丁醇的潜在优势。NADPH是合成异丁醇的关键辅因子，葡萄糖-6-磷酸脱氢酶（Zwf 1）是S.啤酒。在这项研究中，我们研究了过表达ZWF 1对异丁醇滴度的影响。结果表明，工程菌HZAL-7023每克葡萄糖产异丁醇6.22 mg，比出发菌株提高了6.64倍;工程菌HZAL-7023 22-ZWF 1每克葡萄糖产异丁醇11.46 mg，比出发菌株提高了1.82倍。这些结果表明，通过过量表达ZWF 1来提高NADPH供应有助于S.啤酒。这些结果也验证了所提出的增加S.酿酒酵母通过解决辅因子不平衡。本研究为提高异丁醇生物合成提供了新的策略。
Isobutanol is a more promising biofuel than ethanol due to its higher energy density and lower hygroscopicity. Saccharomyces cerevisiae, as a model eukaryote, has the potential advantage to produce isobutanol because of its greater tolerance to higher alcohols. NADPH is a key cofactor for isobutanol synthesis, and glucose-6-phosphate dehydrogenase (Zwf1) is one of the main NADPH-supplying sources in S. cerevisiae. In this study, we investigated the effects of over-expressing ZWF1 on isobutanol titers. Our results showed that engineered strain HZAL-7023 produced 6.22 mg isobutanol per g glucose, which increased by 6.64-fold compared with the parent strain, while engineered strain HZAL-7023 22-ZWF1 produced 11.46 mg isobutanol per g glucose, which increased by 1.82-fold compared with engineered strain HZAL-7023. These results suggested that improvement of NADPH supply through over-expressing ZWF1 contributed to isobutanol biosynthesis in S. cerevisiae. These results also verified the proposed concept of increasing isobutanol titers in S. cerevisiae by resolving cofactor imbalance. Finally, this study provides a new strategy for enhancing isobutanol biosynthesis.