Repository logo

Combining SIMS and mechanistic modelling to reveal nutrient kinetics in an algal-bacterial mutualism.

Published version



Change log


Laeverenz Schlogelhofer, Hannah  ORCID logo
Peaudecerf, François J  ORCID logo
Bunbury, Freddy 
Whitehouse, Martin J 
Foster, Rachel A 


Microbial communities are of considerable significance for biogeochemical processes, for the health of both animals and plants, and for biotechnological purposes. A key feature of microbial interactions is the exchange of nutrients between cells. Isotope labelling followed by analysis with secondary ion mass spectrometry (SIMS) can identify nutrient fluxes and heterogeneity of substrate utilisation on a single cell level. Here we present a novel approach that combines SIMS experiments with mechanistic modelling to reveal otherwise inaccessible nutrient kinetics. The method is applied to study the onset of a synthetic mutualistic partnership between a vitamin B12-dependent mutant of the alga Chlamydomonas reinhardtii and the B12-producing, heterotrophic bacterium Mesorhizobium japonicum, which is supported by algal photosynthesis. Results suggest that an initial pool of fixed carbon delays the onset of mutualistic cross-feeding; significantly, our approach allows the first quantification of this expected delay. Our method is widely applicable to other microbial systems, and will contribute to furthering a mechanistic understanding of microbial interactions.



Chlamydomonas reinhardtii, Mesorhizobium, Models, Biological, Mutation, Symbiosis, Vitamin B 12

Journal Title

PLoS One

Conference Name

Journal ISSN


Volume Title



Public Library of Science (PLoS)
Engineering and Physical Sciences Research Council (EP/J004847/1)
Biotechnology and Biological Sciences Research Council (BB/M011194/1)
Engineering and Physical Sciences Research Council (EP/L015978/1)
BBSRC (BB/T010525/1)
Biotechnology and Biological Sciences Research Council (BB/I013164/1)
Is derived from: