Environmental modulators of algae-bacteria interactions at scale

Photosynthetic microbes associated with non-photosynthetic, heterotrophic bacteria play a crucial role in global primary production, nutrient cycling, and industrial processes. Understanding these phototroph-heterotroph associations is therefore important but remains challenging because they reside in chemically complex aquatic and terrestrial environments. We do not understand how the myriad of environmental parameters, from nutrient availability to pH, impact interactions between phototrophs and their heterotrophic partners. Here, we leverage a massively parallel droplet microfluidic platform that enables us to interrogate algae-bacteria interactions in >100,000 communities across ~525 environmental conditions with varying pH, phosphorous availability. carbon availability and carbon source identity. By developing a statistical framework to dissect interactions in this complex dataset, we reveal that the dependence of algae-bacteria interactions on nutrient availability is strongly modulated by pH and buffering capacity. Furthermore, we show that the chemical identity of the available organic carbon source controls how pH, buffering capacity, and nutrient availability modulate algae-bacteria interactions. By leveraging a high-throughput platform, our study reveals the previously underappreciated role of pH in modulating phototroph-heterotroph interactions.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• Gopalakrishnappa, Chandana

Contributors dc:contributor

• Kuehn, Seppe
• Golding, Ido
• Heath, Katy
• Maslov, Sergei

• Droplet Microfluidics
• High-throughput
• Microbial Ecology
• Phototroph-heterotroph Interactions
• High Dimensional Environments
• Statistical Modeling

Statement dc:rights

• Copyright 2023 Chandana Gopalakrishnappa

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/122189

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F122189