The search for gasoline substitutes has grown in recent decades, leading to the increased production of ethanol as viable alternative. However, research in recent years has shown that butanol exhibits various advantages over ethanol as a biofuel. Furthermore, butanol can also be used as a chemical platform, serving as an intermediate product and as a solvent in industrial reactions. This alcohol is naturally produced by some Clostridium species; however, Clostridial fermentation processes still have inherent problems, which focuses the interest on Saccharomyces cerevisiae for butanol production, as an alternative organism for the production of this alcohol. S. cerevisiae exhibits great adaptability to industrial conditions and can be modified with a wide range of genetic tools. Although S. cerevisiae is known to naturally produce isobutanol, the n-butanol synthesis pathway has not been well established in wild S. cerevisiae strains. Two strategies are most commonly used for of S. cerevisiae butanol production: the heterologous expression of the Clostridium pathway or the amino acid uptake pathways. However, butanol yields produced from S. cerevisiae are lower than ethanol yield. Thus, there are still many challenges needed to be overcome, which can be minimized through genetic and evolutive engineering, for butanol production by yeast to become a reality.

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酿酒酵母生产丁醇：前景、策略和挑战

近几十年来，对汽油替代品的研究不断增加，导致乙醇作为可行替代品的产量增加。然而，近年来的研究表明，丁醇作为生物燃料表现出优于乙醇的各种优势。此外，丁醇还可用作化学平台，用作中间产品和工业反应中的溶剂。这种酒精是由某些梭菌属自然产生的；然而，梭菌发酵过程仍然存在固有的问题，因此人们将兴趣集中在用于生产丁醇的酿酒酵母，作为生产这种酒精的替代生物。S. cerevisiae 对工业条件表现出极大的适应性，并且可以使用广泛的遗传工具进行修改。尽管已知酿酒酵母会自然产生异丁醇，在野生酿酒酵母菌株中尚未很好地建立正丁醇合成途径。两种策略最常用于酿酒酵母丁醇生产：梭菌途径的异源表达或氨基酸摄取途径。然而，由酿酒酵母生产的丁醇产量低于乙醇产量。因此，要使酵母生产丁醇成为现实，仍然需要克服许多挑战，这些挑战可以通过遗传和进化工程最小化。酿酒酵母的产量低于乙醇产量。因此，要使酵母生产丁醇成为现实，仍然需要克服许多挑战，这些挑战可以通过遗传和进化工程最小化。酿酒酵母的产量低于乙醇产量。因此，要使酵母生产丁醇成为现实，仍然需要克服许多挑战，这些挑战可以通过遗传和进化工程最小化。