Mixed and membrane-separated culturing of synthetic cyanobacteria-yeast consortia reveals metabolic cross-talk mimicking natural cyanolichens

• Published in: Scientific reports Vol. 14; no. 1; pp. 25303 - 19
• Main Authors: Bohutskyi, Pavlo, Pomraning, Kyle R., Jenkins, Jackson P, Kim, Young-Mo, Poirier, Brenton C, Betenbaugh, Michael J, Magnuson, Jon K
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 25.10.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 631/326/2565; 631/326/2565/855; Alcohols; Amino acids; BASIC BIOLOGICAL SCIENCES; Bioreactors; Bioreactors - microbiology; Biotechnology; Carbon cycle; Carbon dioxide; Coculture Techniques - methods; Cross-feeding; Cyanobacteria - genetics; Cyanobacteria - metabolism; Environmental science; Germfree; Humanities and Social Sciences; Intermediates; Lichens; Lichens - metabolism; Lichens - microbiology; Membrane-separated bioreactor; Metabolic engineering; Metabolism; Metabolite exchange; Metabolites; Microbial activity; Microbial communities; Microbial community; Microbial Consortia; Microbial ecology; Microbial Interactions; Microbiomes; multidisciplinary; Nitrogen cycle; Phototroph-heterotroph co-culture; Rhodotorula - genetics; Rhodotorula - metabolism; Science; Science (multidisciplinary); Sugar; Synechococcus - genetics; Synechococcus - metabolism; Synthetic lichen; Tricarboxylic acid cycle; Yeast; Membrane-separated bioreactor; Synthetic lichen; Metabolite exchange; Phototroph-heterotroph co-culture; Cross-feeding; Microbial community
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-74743-4

Metabolite exchange mediates crucial interactions in microbial communities, significantly impacting global carbon and nitrogen cycling. Understanding these chemically-mediated interactions is essential for elucidating natural community functions and developing engineered synthetic communities. This study investigated membrane-separated bioreactors (mBRs) as a novel tool to identify transient metabolites and their producers/consumers in mixed microbial communities. We compared three co-culture methods (direct mixed, 2-chamber mBR, and 3-chamber mBR) to grow a synthetic binary community of the cyanobacterium Synechococcus elongatus PCC 7942 and the fungus Rhodotorula toruloides NBRC 0880, as well as axenic S. elongatus . Despite not being natural lichen constituents, these organisms exhibited interactions resembling those in cyanolichens. S. elongatus fixed CO 2 into sugars as the primary shared metabolite, while R. toruloides secreted various biochemicals, predominantly sugar alcohols, mirroring the metabolite exchange observed in natural lichens. The mBR systems successfully captured metabolite gradients and revealed rapidly consumed compounds, including TCA cycle intermediates and amino acids. Our approach demonstrated that the 2-chamber mBR optimally balanced metabolite exchange and growth dynamics. This study provides insights into cross-species metabolic interactions and presents a valuable tool for investigating and engineering synthetic microbial communities with potential applications in biotechnology and environmental science.