New insights into the mechanical properties of Acanthamoeba castellanii cysts as revealed by phonon microscopy

Pérez-Cota, Fernando; Smith, Richard J.; Elsheikha, Hany M.; Clark, Matt

Abstract

The single cell eukaryotic protozoan Acanthamoeba castellanii exhibits a remarkable ability to switch from a vegetative trophozoite stage to a cystic form, in response to stressors. This phenotypic switch involves changes in gene expression and synthesis of the cell wall, which affects the ability of the organism to resist biocides and chemotherapeutic medicines. Given that encystation is a fundamental survival mechanism in the life cycle of A. castellanii, understanding of this process should have significant environmental and medical implications. In the present study, we investigated the mechanism of A. castellanii encystation using a novel phonon microscopy technique at the single cell level. Phonon microscopy is an emerging technique to image cells using laser-generated sub-optical wavelength phonons. This imaging modality can image with contrast underpinned by mechanical properties of cells at an optical or higher resolution. Our results show that the Brillouin frequency, a shift of the colour of light induced by phonons, evolves in three well defined frequency bands instead of a simple shift in frequency. These observations confirm previous results from literature and provide new insights into the capacity of A. castellanii cyst to react quickly in harsh environments.

Citation

Pérez-Cota, F., Smith, R. J., Elsheikha, H. M., & Clark, M. (2019). New insights into the mechanical properties of Acanthamoeba castellanii cysts as revealed by phonon microscopy. Biomedical Optics Express, 10(5), 2399-2408. https://doi.org/10.1364/BOE.10.002399

• Journal Article Type: Article
• Acceptance Date: Feb 20, 2019
• Online Publication Date: Apr 15, 2019
• Publication Date: May 1, 2019
• Deposit Date: Mar 28, 2019
• Publicly Available Date: Apr 16, 2019
• Journal: Biomedical Optics Express
• Electronic ISSN: 2156-7085
• Publisher: Optical Society of America
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 5
• Pages: 2399-2408
• DOI: https://doi.org/10.1364/BOE.10.002399
• Keywords: Biotechnology; Atomic and Molecular Physics, and Optics
• Public URL: https://nottingham-repository.worktribe.com/output/1700332
• Publisher URL: https://www.osapublishing.org/boe/abstract.cfm?uri=boe-10-5-2399
• Additional Information: This article is maintained by: OSA - The Optical Society; Crossref DOI link to publisher maintained version: https://doi.org/10.1364/BOE.10.002399; Article type: research-article; Similarity check: Screened by Similarity Check; Peer reviewed: Yes; Review process: Single blind; Received: 30 November 2018; Accepted: 8 March 2019; Published: 15 April 2019; Copyright: Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.