An Escherichia coli nitrogen starvation response is important for mutualistic coexistence with Rhodopseudomonas palustris.

An Escherichia coli nitrogen starvation response is important for mutualistic coexistence with Rhodopseudomonas palustris. Appl Environ Microbiol. 2018 May 04;: Authors: McCully AL, Behringer MG, Gliessman JR, Pilipenko EV, Mazny JL, Lynch M, Drummond DA, McKinlay JB Abstract Microbial mutualistic cross-feeding interactions are ubiquitous and can drive important community functions. Engaging in cross-feeding undoubtedly affects the physiology and metabolism of individual species involved. However, the nature in which an individual's physiology is influenced by cross-feeding and the importance of those physiological changes for the mutualism have received little attention. We previously developed a genetically tractable coculture to study bacterial mutualisms. The coculture consists of fermentative Escherichia coli and phototrophic Rhodopseudomonas palustris In this coculture, E. coli anaerobically ferments sugars into excreted organic acids as a carbon source for R. palustris In return, a genetically-engineered R. palustris constitutively converts N2 into NH4+, providing E. coli with essential nitrogen. Using RNA-seq and proteomics, we identified transcript and protein levels that differ in each partner when grown in coculture versus monoculture. When in coculture with R. palustris, E. coli gene-expression changes resembled a nitrogen starvation response under the control of the transcriptional regulator NtrC. By genetically disrupti...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research