Center for Biomedical Technology, Universidad Politécnica de Madrid, E-28223 Pozuelo de Alarcón, Spain.
Departamento de Ciencia de Materiales, ETSI de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, E-28040 Madrid, Spain.
Phys Rev E. 2017 Aug;96(2-1):022402. doi: 10.1103/PhysRevE.96.022402. Epub 2017 Aug 8.
The study of fungal cells is of great interest due to their importance as pathogens and as fermenting fungi and for their appropriateness as model organisms. The differential pressure between the hyphal cytoplasm and the bordering medium is essential for the growth process, because the pressure is correlated with the growth rate. Notably, during the invasion of tissues, the external pressure at the tip of the hypha may be different from the pressure in the surrounding medium. We report the use of a method, based on the micropipette-aspiration technique, to study the influence of this external pressure at the hyphal tip. Moreover, this technique makes it possible to study hyphal growth mechanics in the case of very thin hyphae, not accessible to turgor pressure probes. We found a correlation between the local pressure at the tip and the growth rate for the species Arpergillus nidulans. Importantly, the proposed method allows one to measure the pressure at the tip required to arrest the hyphal growth. Determining that pressure could be useful to develop new medical treatments for fungal infections. Finally, we provide a mechanical model for these experiments, taking into account the cytoplasm flow and the wall deformation.
由于真菌细胞作为病原体和发酵真菌的重要性,以及它们作为模式生物的适宜性,对其进行研究具有重要意义。菌丝细胞质和边界介质之间的压差对于生长过程至关重要,因为压力与生长速率相关。值得注意的是,在组织入侵过程中,菌丝尖端的外部压力可能与周围介质中的压力不同。我们报告了一种基于微吸管抽吸技术的方法,用于研究菌丝尖端外部压力的影响。此外,该技术使得研究菌丝生长力学成为可能,即使是对于非常细的菌丝,也可以使用膨压探针进行研究。我们发现局部尖端压力与物种 Aspergillus nidulans 的生长速率之间存在相关性。重要的是,所提出的方法允许测量停止菌丝生长所需的尖端压力。确定该压力对于开发治疗真菌感染的新方法可能很有用。最后,我们提供了一个用于这些实验的力学模型,考虑了细胞质流动和细胞壁变形。