School of Food Engineering, University of Campinas, Rua Monteiro Lobato 80, Campinas, SP, 13083-862, Brazil.
Department of Chemical Engineering, University of Sao Paulo, Av. Prof. Luciano Gualberto 380, São Paulo, SP, 05508-010, Brazil.
Appl Microbiol Biotechnol. 2018 Mar;102(5):2101-2116. doi: 10.1007/s00253-017-8732-4. Epub 2018 Feb 3.
The budding yeast Saccharomyces cerevisiae plays an important role in biotechnological applications, ranging from fuel ethanol to recombinant protein production. It is also a model organism for studies on cell physiology and genetic regulation. Its ability to grow under anaerobic conditions is of interest in many industrial applications. Unlike industrial bioreactors with their low surface area relative to volume, ensuring a complete anaerobic atmosphere during microbial cultivations in the laboratory is rather difficult. Tiny amounts of O that enter the system can vastly influence product yields and microbial physiology. A common procedure in the laboratory is to sparge the culture vessel with ultrapure N gas; together with the use of butyl rubber stoppers and norprene tubing, O diffusion into the system can be strongly minimized. With insights from some studies conducted in our laboratory, we explore the question 'how anaerobic is anaerobiosis?'. We briefly discuss the role of O in non-respiratory pathways in S. cerevisiae and provide a systematic survey of the attempts made thus far to cultivate yeast under anaerobic conditions. We conclude that very few data exist on the physiology of S. cerevisiae under anaerobiosis in the absence of the anaerobic growth factors ergosterol and unsaturated fatty acids. Anaerobicity should be treated as a relative condition since complete anaerobiosis is hardly achievable in the laboratory. Ideally, researchers should provide all the details of their anaerobic set-up, to ensure reproducibility of results among different laboratories.
budding 酵母酿酒酵母在生物技术应用中起着重要作用，从燃料乙醇到重组蛋白生产。它也是研究细胞生理学和遗传调控的模式生物。它在厌氧条件下生长的能力在许多工业应用中很有趣。与工业生物反应器相比，其表面积相对于体积较小，因此在实验室中进行微生物培养时，确保完全的厌氧气氛相当困难。进入系统的少量 O 会极大地影响产品产量和微生物生理学。实验室中的常见程序是用超纯 N 气体对培养容器进行吹气；同时使用丁基橡胶塞和 norprene 管，可大大减少 O 向系统中的扩散。根据我们实验室进行的一些研究，我们探讨了“厌氧性的厌氧性如何”的问题。我们简要讨论了 O 在酿酒酵母非呼吸途径中的作用，并对迄今为止为在厌氧条件下培养酵母而进行的尝试进行了系统调查。我们得出的结论是，在没有厌氧生长因子麦角固醇和不饱和脂肪酸的情况下，关于酿酒酵母在厌氧条件下的生理学的资料非常少。厌氧性应该被视为一种相对的条件，因为在实验室中几乎不可能实现完全的厌氧性。理想情况下，研究人员应该提供他们的厌氧设置的所有细节，以确保不同实验室之间结果的可重复性。
