Download MendeleyDiurnal metabolic control in cyanobacteria requires perception of second messenger signaling molecule c-di-AMP by the carbon control protein SbtB.
Selim, K.A., Haffner, M., Burkhardt, M., Mantovani, O., Neumann, N., Albrecht, R., Seifert, R., Kruger, L., Stulke, J., Hartmann, M.D., Hagemann, M., Forchhammer, K.(2021) Sci Adv 7: eabk0568-eabk0568
- PubMed: 34878830
- DOI: https://doi.org/10.1126/sciadv.abk0568
- Primary Citation of Related Structures:
7OBJ - PubMed Abstract:
Because of their photosynthesis-dependent lifestyle, cyanobacteria evolved sophisticated regulatory mechanisms to adapt to oscillating day-night metabolic changes. How they coordinate the metabolic switch between autotrophic and glycogen-catabolic metabolism in light and darkness is poorly understood. Recently, c-di-AMP has been implicated in diurnal regulation, but its mode of action remains elusive. To unravel the signaling functions of c-di-AMP in cyanobacteria, we isolated c-di-AMP receptor proteins. Thereby, the carbon-sensor protein SbtB was identified as a major c-di-AMP receptor, which we confirmed biochemically and by x-ray crystallography. In search for the c-di-AMP signaling function of SbtB, we found that both SbtB and c-di-AMP cyclase–deficient mutants showed reduced diurnal growth and that c-di-AMP–bound SbtB interacts specifically with the glycogen-branching enzyme GlgB. Accordingly, both mutants displayed impaired glycogen synthesis during the day and impaired nighttime survival. Thus, the pivotal role of c-di-AMP in day-night acclimation can be attributed to SbtB-mediated regulation of glycogen metabolism.
Organizational Affiliation:
Organismic Interactions Department, Interfaculty Institute for Microbiology and Infection Medicine, Cluster of Excellence 'Controlling Microbes to Fight Infections', Tübingen University, Auf der Morgenstelle 28, 72076 Tübingen, Germany.
