Inferring cell division kinetics in Chlamydomonas reinhardtii from flow cytometry with Gaussian process regression

Author(s)
Michiel Busschaert, Michael Schagerl, Christian Griebler, Florence H. Vermeire, Steffen Waldherr
Abstract

Green algae, such as Chlamydomonas reinhardtii, are promising candidates for various industrial applications. For microorganisms, cell size relates to metabolic activity and cellular composition, among others, and is thus a highly relevant property for bioprocess operations. Besides time-consuming microscopy measurements, cell sizes can be estimated indirectly for example with flow cytometry based on light scattering, resulting in a measured size distribution. However, calibration for absolute cell sizes is obstructed by the optical properties of the involved particles, resulting in less accurate size distributions, which in turn can hinder applications such as model development or process monitoring. In this study, a novel approach is proposed to improve the estimation accuracy of the cell size distribution by utilizing a physical model on light scattering around a sphere. Benchmarked with microscopy image analysis, the model shows substantial improvement. Using the corrected size distribution, the cell division rate is inferred with an extended Gaussian process regression used upon a population balance model. The resulting model is able to accurately describe the observed size distribution with the estimated division kinetics. The approach is tested using data obtained from the cultivation of C. reinhardtii as a model organism. The results provide mechanistic insight into C. reinhardtii cell division and cell size heterogeneity.

Organisation(s)
Functional and Evolutionary Ecology
External organisation(s)
Katholieke Universiteit Leuven
Journal
Bioresource Technology
Volume
443
ISSN
0960-8524
DOI
https://doi.org/10.1016/j.biortech.2025.133835
Publication date
03-2026
Peer reviewed
Yes
Austrian Fields of Science 2012
209006 Industrial biotechnology
Keywords
ASJC Scopus subject areas
Environmental Engineering, Bioengineering, Renewable Energy, Sustainability and the Environment, Waste Management and Disposal
Portal url
https://ucrisportal.univie.ac.at/en/publications/f6ae4c5d-44ab-4650-bf85-f252ef453fe2