van Dissel Dino, van Wezel Gilles P
Molecular Biotechnology, Institute of Biology, Leiden University, PO Box 9505, 2300RA, Leiden, The Netherlands.
Antonie Van Leeuwenhoek. 2018 Mar;111(3):457-469. doi: 10.1007/s10482-017-0967-7. Epub 2017 Nov 1.
Actinobacteria are prolific producers of secondary metabolites and industrially relevant enzymes. Growth of these mycelial micro-organisms in small culture volumes is challenging due to their complex morphology. Since morphology and production are typically linked, scaling down culture volumes requires better control over morphogenesis. In larger scale platforms, ranging from shake flasks to bioreactors, the hydrodynamics play an important role in shaping the morphology and determining product formation. Here, we report on the effects of agitation on the mycelial morphology of Streptomyces lividans grown in microtitre plates. Our work shows that at the appropriate agitation rates cultures can be scaled down to volumes as small as 100 µl while maintaining the same morphology as seen in larger scale platforms. Using image analysis and principal component analysis we compared the morphologies of the cultures; when agitated at 1400-1600 rpm the mycelial morphology in micro-cultures was similar to that obtained in shake flasks, while product formation was also maintained. Our study shows that the morphology of actinobacteria in micro-cultures can be controlled in a similar manner as in larger scale cultures by carefully controlling the mixing rate. This could facilitate high-throughput screening and upscaling.
放线菌是次生代谢产物和具有工业相关性酶的丰富生产者。由于其复杂的形态，在小体积培养中培养这些丝状微生物具有挑战性。由于形态与产物合成通常相关联，缩小培养体积需要更好地控制形态发生。在从摇瓶到生物反应器的较大规模平台中，流体动力学在塑造形态和决定产物形成方面起着重要作用。在此，我们报告了搅拌对在微孔板中生长的变铅青链霉菌菌丝形态的影响。我们的工作表明，在适当的搅拌速率下，培养体积可缩小至小至100微升，同时保持与较大规模平台中所见相同的形态。通过图像分析和主成分分析，我们比较了培养物的形态；当以1400 - 1600转/分钟搅拌时，微培养中的菌丝形态与摇瓶中获得的形态相似，同时产物合成也得以维持。我们的研究表明，通过仔细控制混合速率，微培养中放线菌的形态可以以与较大规模培养类似的方式进行控制。这可以促进高通量筛选和放大培养。
