Skip to main content

Research Repository

Advanced Search

Agr Quorum Sensing influences the Wood-Ljungdahl pathway in Clostridium autoethanogenum

Agr Quorum Sensing influences the Wood-Ljungdahl pathway in Clostridium autoethanogenum Thumbnail


Pawel Piatek

Mahendra Raut

Phillip C. Wright

Sean Simpson



Acetogenic bacteria are capable of fermenting CO2 and carbon monoxide containing waste-gases into a range of platform chemicals and fuels. Despite major advances in genetic engineering and improving these biocatalysts, several important physiological functions remain elusive. Among these is quorum sensing, a bacterial communication mechanism known to coordinate gene expression in response to cell population density. Two putative agr systems have been identified in the genome of Clostridium autoethanogenum suggesting bacterial communication via autoinducing signal molecules. Signal molecule-encoding agrD1 and agrD2 genes were targeted for in-frame deletion. During heterotrophic growth on fructose as a carbon and energy source, single deletions of either gene did not produce an observable phenotype. However, when both genes were simultaneously inactivated, final product concentrations in the double mutant shifted to a 1.5:1 ratio of ethanol:acetate, compared to a 0.2:1 ratio observed in the wild type control, making ethanol the dominant fermentation product. Moreover, CO2 re-assimilation was also notably reduced in both hetero- and autotrophic growth conditions. These findings were supported through comparative proteomics, which showed lower expression of carbon monoxide dehydrogenase, formate dehydrogenase A and hydrogenases in the ?agrD1?agrD2 double mutant, but higher levels of putative alcohol and aldehyde dehydrogenases and bacterial micro-compartment proteins. These findings suggest that Agr quorum sensing, and by inference, cell density play a role in carbon resource management and use of the Wood-Ljungdahl pathway as an electron sink.


Piatek, P., Humphreys, C., Raut, M., Wright, P. C., Simpson, S., Köpke, M., …Winzer, K. (2022). Agr Quorum Sensing influences the Wood-Ljungdahl pathway in Clostridium autoethanogenum. Scientific Reports, 12(1), Article 411.

Journal Article Type Article
Acceptance Date Dec 7, 2021
Online Publication Date Jan 10, 2022
Publication Date Jan 10, 2022
Deposit Date Dec 16, 2021
Publicly Available Date Jan 11, 2022
Journal Scientific Reports
Print ISSN 2045-2322
Electronic ISSN 2045-2322
Publisher Nature Publishing Group
Peer Reviewed Peer Reviewed
Volume 12
Issue 1
Article Number 411
Keywords Multidisciplinary
Public URL
Publisher URL
Additional Information Received: 10 September 2021; Accepted: 7 December 2021; First Online: 10 January 2022; : The authors declare no competing interests.


You might also like

Downloadable Citations