Single cell ecophysiology in structured microbial communities

Professor Victoria Orphan and graduate student
Grayson Chadwick in the SIMS lab
Photo credit Ryan Forbes

Image modified from: Visscher, Nicolaes.
Orbis Terrarum Nova Et Accuratissima Tabula.

We are using single cell stable isotope measurements by FISH-nanoSIMS combined with geostatistical methods to determine cell-specific variation in ecophysiology and interspecies interactions (e.g. antagonistic, competitive, or mutualistic) between spatially proximal microorganisms within structured microbial consortia and communities in the environment.

This methodological approach is being used to learn about the interactions between methane-oxidizing ANME archaea and co-associated sulfate-reducing bacteria from deep sea methane seeps. Investigations of ANME consortia have uncovered a rich diversity in both membership and spatial associations across a range of anoxic environments. The fundamental biochemical and kinetic underpinnings of these symbiotic associations is still not well understood, and is hampered by low biomass yields, poorly-defined nutritional and physico-chemical requirements, and slow growth. The advancement and application of microanalytical techniques that retain spatial information and generate resolution at the level of single microbial cells, such as the nanoSIMS-based techniques developed in the Orphan lab (e.g. McGlynn et al 2015 Nature) or single cell/consortia level ‘omics (Hatzenpichler et al 2016 PNAS) provides targeted, activity-based methods for studying as yet uncultured methanotrophic consortia, and other key microbial associations recovered directly from environmental samples.

Single Cell Activity Mapping