Baur Tina, Dürre Peter
Institut für Mikrobiologie und Biotechnologie, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
Microorganisms. 2023 Mar 7;11(3):685. doi: 10.3390/microorganisms11030685.
Propionate is an important platform chemical that is available through petrochemical synthesis. Bacterial propionate formation is considered an alternative, as bacteria can convert waste substrates into valuable products. In this regard, research primarily focused on propionibacteria due to high propionate titers achieved from different substrates. Whether other bacteria could also be attractive producers is unclear, mostly because little is known about these strains. Therefore, two thus far less researched strains, and , were investigated with regard to their morphologic and metabolic features. Microscopic analyses revealed a negative Gram reaction despite a Gram-positive cell wall as well as surface layers for both strains. Furthermore, growth, product profiles, and the potential for propionate formation from sustainable substrates, i.e., ethanol or lignocellulosic sugars, were assessed. Results showed that both strains can oxidize ethanol to different extents. While only partially used ethanol, converted 28.3 mM ethanol to 16.4 mM propionate. Additionally, the ability of to produce propionate from lignocellulose-derived substrates was analyzed, leading to propionate concentrations of up to 14.5 mM. Overall, this work provides new insights into the physiology of the strains, which can be used to develop effective propionate producer strains.
丙酸盐是一种重要的平台化学品，可通过石化合成获得。细菌合成丙酸盐被认为是一种替代方法，因为细菌可以将废弃底物转化为有价值的产品。在这方面，由于不同底物能产生高丙酸盐滴度，研究主要集中在丙酸杆菌上。其他细菌是否也可能是有吸引力的生产者尚不清楚，主要是因为对这些菌株了解甚少。因此，对迄今为止研究较少的两株菌株和进行了形态学和代谢特征方面的研究。显微镜分析显示，尽管两株菌株都有革兰氏阳性细胞壁和表面层，但革兰氏反应均为阴性。此外，还评估了它们的生长、产物谱以及利用可持续底物（即乙醇或木质纤维素糖）合成丙酸盐的潜力。结果表明，两株菌株都能不同程度地氧化乙醇。仅部分利用乙醇，而将28.3 mM乙醇转化为16.4 mM丙酸盐。此外，还分析了利用木质纤维素衍生底物生产丙酸盐的能力，丙酸盐浓度高达14.5 mM。总体而言，这项工作为菌株的生理学提供了新的见解，可用于开发有效的丙酸盐生产菌株。
