Technical University of Munich, School of Life Sciences Weihenstephan, Chair of Process Systems Engineering, Freising, Germany.
Department of Applied and Molecular Microbiology, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany.
Biotechnol Bioeng. 2019 Jun;116(6):1355-1365. doi: 10.1002/bit.26956. Epub 2019 Mar 8.
Filamentous fungi are widely used in the production of biotechnological compounds. Since their morphology is strongly linked to productivity, it is a key parameter in industrial biotechnology. However, identifying the morphological properties of filamentous fungi is challenging. Owing to a lack of appropriate methods, the detailed three-dimensional morphology of filamentous pellets remains unexplored. In the present study, we used state-of-the-art X-ray microtomography (µCT) to develop a new method for detailed characterization of fungal pellets. µCT measurements were performed using freeze-dried pellets obtained from submerged cultivations. Three-dimensional images were generated and analyzed to locate and quantify hyphal material, tips, and branches. As a result, morphological properties including hyphal length, tip number, branch number, hyphal growth unit, porosity, and hyphal average diameter were ascertained. To validate the potential of the new method, two fungal pellets were studied-one from Aspergillus niger and the other from Penicillium chrysogenum. We show here that µCT analysis is a promising tool to study the three-dimensional structure of pellet-forming filamentous microorganisms in utmost detail. The knowledge gained can be used to understand and thus optimize pellet structures by means of appropriate process or genetic control in biotechnological applications.
丝状真菌广泛应用于生物技术化合物的生产。由于其形态与生产力密切相关，因此它是工业生物技术的关键参数。然而，鉴定丝状真菌的形态特征具有挑战性。由于缺乏适当的方法，丝状菌球的详细三维形态仍未得到探索。在本研究中，我们使用最先进的 X 射线微断层扫描（µCT）开发了一种新的方法，用于详细表征真菌球。µCT 测量是使用从浸没培养中获得的冻干菌球进行的。生成并分析三维图像以定位和量化菌丝材料、尖端和分支。结果确定了包括菌丝长度、尖端数量、分支数量、菌丝生长单元、孔隙率和菌丝平均直径在内的形态特征。为了验证新方法的潜力，我们研究了两个真菌球，一个来自黑曲霉，另一个来自产黄青霉。我们在这里表明，µCT 分析是一种很有前途的工具，可以最详细地研究形成菌球的丝状微生物的三维结构。所获得的知识可用于通过生物技术应用中的适当过程或遗传控制来理解和优化菌球结构。
