Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA.
Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA; Center for Bioenergy and Bioproducts, Auburn University, Auburn, AL 36849, USA.
Bioresour Technol. 2017 Dec;245(Pt A):426-433. doi: 10.1016/j.biortech.2017.09.024. Epub 2017 Sep 5.
Clostridium saccharoperbutylacetonicum N1-4 is well known as a hyper-butanol producing strain. However, little information is available concerning its butanol production mechanism and the development of more robust strains. In this study, key biosynthetic genes (either endogenous or exogenous) including the sol operon (bld-ctfA-ctfB-adc), adhE1, adhE1, thl, thlA1, thlA and the expression cassette EC (thl-hbd-crt-bcd) were overexpressed in C. saccharoperbutylacetonicum N1-4 to evaluate their potential in enhancement of butanol production. The overexpression of sol operon increased ethanol production by 400%. The overexpression of adhE1 and adhE resulted in a 5.6- and 4.9-fold higher ethanol production, respectively, producing final acetone-butanol-ethanol (ABE) titers (30.6 and 30.1gL) of among the highest as ever reported for solventogenic clostridia. The most significant increase of butanol production (by 13.7%) and selectivity (73.7%) was achieved by the overexpression of EC. These results provides a solid foundation and essential references for the further development of more robust strains.
丙酮丁醇梭菌 N1-4 是众所周知的高产丁醇菌株。然而，关于其丁醇生产机制和更健壮菌株的开发，信息很少。在本研究中，过表达了关键生物合成基因（内源性或外源性），包括 sol 操纵子（bld-ctfA-ctfB-adc）、adhE1、adhE2、thl、thlA1、thlA 和表达盒 EC（thl-hbd-crt-bcd），以评估它们在提高丁醇产量方面的潜力。sol 操纵子的过表达使乙醇产量增加了 400%。adhE1 和 adhE2 的过表达分别使乙醇产量提高了 5.6 倍和 4.9 倍，产生了溶剂梭菌中报告的最高终丙酮丁醇乙醇（ABE）浓度（30.6 和 30.1gL）之一。通过过表达 EC，丁醇产量（提高了 13.7%）和选择性（提高了 73.7%）得到了最大的提高。这些结果为进一步开发更健壮的菌株提供了坚实的基础和重要的参考。
