De Clercq Veerle, Roelants Sophie L K W, Castelein Martijn G, De Maeseneire Sofie L, Soetaert Wim K
Centre for Industrial Biotechnology and Biocatalysis (InBio.be), Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
J Fungi (Basel). 2021 Oct 28;7(11):917. doi: 10.3390/jof7110917.
The yeast distinguishes itself from other yeasts by its potential of producing copious amounts of the secondary metabolites sophorolipids (SLs): these are glycolipid biosurfactants composed out of a(n) (acetylated) sophorose moiety and a lipid tail. Although SLs are the subject of numerous research papers and have been commercialized, e.g., in eco-friendly cleaning solutions, the natural function of SLs still remains elusive. This research article investigates several hypotheses for why invests that much energy in the production of SLs, and we conclude that the main natural function of SLs in is niche protection: (1) the extracellular storage of an energy-rich, yet metabolically less accessible carbon source that can be utilized by upon conditions of starvation with (2) antimicrobial properties. In this way, creates a dual advantage in competition with other microorganisms. Additionally, SLs can expedite growth on rapeseed oil, composed of triacylglycerols which are hydrophobic substrates present in the yeasts' environment, for a non-SL producing strain (). It was also found that-at least under lab conditions-SLs do not provide protection against high osmotic pressure prevalent in sugar-rich environments such as honey or nectar present in the natural habitat of .
这种酵母通过其产生大量次生代谢产物槐糖脂（SLs）的潜力与其他酵母区分开来：这些是糖脂生物表面活性剂，由（乙酰化的）槐糖部分和脂质尾巴组成。尽管SLs是众多研究论文的主题并且已经商业化，例如用于环保清洁溶液中，但SLs的自然功能仍然难以捉摸。这篇研究文章探讨了关于[酵母名称]为何在SLs生产上投入如此多能量的几种假设，并且我们得出结论，[酵母名称]中SLs的主要自然功能是生态位保护：（1）细胞外储存一种能量丰富但代谢上较难利用的碳源，在饥饿条件下[酵母名称]可以利用该碳源，以及（2）具有抗菌特性。通过这种方式，[酵母名称]在与其他微生物的竞争中创造了双重优势。此外，对于非SL生产菌株（[菌株名称]）而言，SLs可以加快其在由三酰甘油组成的菜籽油上的生长，三酰甘油是酵母环境中存在的疏水底物。还发现，至少在实验室条件下，SLs不能为[酵母名称]自然栖息地中存在的富含糖的环境（如蜂蜜或花蜜）中普遍存在的高渗透压提供保护。
