Quantifying the dominant growth mechanisms of dimorphic yeast using a lattice-based model

Authored by Benjamin J Binder, Hayden Tronnolone, Jennifer M Gardner, Joanna F Sundstrom, Vladimir Jiranek, Stephen G Oliver

Date Published: 2017

DOI: 10.1098/rsif.2017.0314

Sponsors: Australian Research Council (ARC)

Platforms: MATLAB

Model Documentation: Other Narrative Mathematical description

Model Code URLs: https://www-ncbi-nlm-nih-gov.ezproxy1.lib.asu.edu/pmc/articles/PMC5636268/bin/rsif20170314supp2.m

Abstract

A mathematical model is presented for the growth of yeast that incorporates both dimorphic behaviour and nutrient diffusion. The budding patterns observed in the standard and pseudohyphal growth modes are represented by a bias in the direction of cell proliferation. A set of spatial indices is developed to quantify the morphology and compare the relative importance of the directional bias to nutrient concentration and diffusivity on colony shape. It is found that there are three different growth modes: uniform growth, diffusion-limited growth (DLG) and an intermediate region in which the bias determines the morphology. The dimorphic transition due to nutrient limitation is investigated by relating the directional bias to the nutrient concentration, and this is shown to replicate the behaviour observed in vivo. Comparisons are made with experimental data, from which it is found that the model captures many of the observed features. Both DLG and pseudohyphal growth are found to be capable of generating observed experimental morphologies.

Tags

Agent-based models patterns Aggregation Saccharomyces-cerevisiae Bacillus-subtilis Agar plates Dimorphic yeast Diffusion-limited growth Filamentous growth Coordinated development Pseudohyphal growth Colony morphology