Multicellular microorganisms: laboratory versus nature

Abstract

Our present in-depth knowledge of the physiology and regulatory mechanisms of microorganisms has arisen from our ability to remove them from their natural, complex ecosystems into pure liquid cultures. These cultures are grown under optimized laboratory conditions and allow us to study microorganisms as individuals. However, microorganisms naturally grow in conditions that are far from optimal, which causes them to become organized into multicellular communities that are better protected against the harmful environment. Moreover, this multicellular existence allows individual cells to differentiate and acquire specific properties, such as forming resistant spores, which benefit the whole population. The relocation of natural microorganisms to the laboratory can result in their adaptation to these favourable conditions, which is accompanied by complex changes that include the repression of some protective mechanisms that are essential in nature. Laboratory microorganisms that have been cultured for long periods under optimized conditions might therefore differ markedly from those that exist in natural ecosystems.

Whi2p links nutritional sensing to actin-dependent Ras-cAMP-PKA regulation and apoptosis in yeast

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Assessing Genetic Diversity among Brettanomyces Yeasts by DNA Fingerprinting and Whole-Genome Sequencing

“…This also resembles the findings of Vigentini et al (16), who found that almost all their wild (wine) B. bruxellensis isolates were clearly separated from the CBS reference strains, representing isolates from different niches, also including wine isolates. It remains to be investigated whether these differences have a biological meaning or can be explained by the fact that the reference strains have become adapted to laboratory conditions, accompanied by changes in their genetic backbone (66).…”

Microbial interactions associated with biofilms attached to Trichodesmium spp. and detrital particles in the ocean

“…It is well known that bacteria in laboratories can exhibit different traits than their relatives in the 'wild' (Palková, 2004). In addition, it is also demonstrated that members of biofilms can change over time under laboratory conditions.…”