Many fluorescent techniques are employed to evaluate the viability and activity of microbial cells used in biotechnology. These techniques are sometimes complex and the interpretation of results opened to misunderstanding. Moreover, new developments are constantly proposed especially concerning a more accurate evaluation of the state of the cells including eukaryotic microorganisms. This paper aims at presenting to biotechnologists unfamiliar with fluorescence the principles of these methods and the related possible pitfalls. It focuses on probes of the physical (integrity and fluidity) and energetical (intracellular pH and membrane potential) state of the cell membrane (bacterial and yeast cells) and presents also other probes (nucleic acids, respiration...) and new technical trends. The specificities of Gram-negative bacterial cells are also discussed.

中文翻译：

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评估微生物生物催化剂的生理状态和活性的荧光探针：原核和真核生物研究指南。

许多荧光技术用于评估生物技术中使用的微生物细胞的活力和活性。这些技术有时很复杂，结果的解释容易引起误解。此外，不断提出新的发展，特别是涉及对包括真核微生物在内的细胞状态的更准确评估。本文旨在向不熟悉荧光的生物技术人员介绍这些方法的原理以及相关的可能的陷阱。它着重于细胞膜（细菌和酵母细胞）的物理（完整性和流动性）和能量（细胞内pH和膜电位）状态的探针，并提出了其他探针（核酸，呼吸...）和新的技术趋势。