Journal article

Publication year: 2004

Pages: 51-56

Journal: Physiologia Plantarum

Volume number: 120

Issue number: 1

ISSN: 0031-9317

eISSN: 1399-3054

DOI Link: https://doi.org/10.1111/j.0031-9317.2004.0218.x

Publisher: Wiley

Abstract: 
This communication presents a short outline of the current knowledge on the molecular basis of P-II signal transduction in unicellular cyanobacteria with respect to the perception of environmental stimuli. First, the general characteristics of the P-II signalling system in unicellular cyanobacteria are presented, the hallmark of which is modification by serine-phosphorylation, as compared to the paradigmatic P-II signal transduction system in proteobacteria, which is based on tyrosyl-uridylylation. Then, the focus is turned on the signals controlling P-II phosphorylation state. Recently, the cellular phosphatase (termed PphA), which specifically dephosphorylates phosphorylated P-II (P-II-P) was identified in Synechocystis sp. strain PCC 6803. With the availability of a PphA-deficient mutant and the purified components for in vitro assay of PphA mediated P-II-P dephosphorylation, novel insights into the signals, to which P-II-P dephosphorylation responds, can be obtained. Here we present an investigation of the response of P-II-P dephosphorylation towards treatments that affect the redox-balance of the cells. Furthermore, a possible role of varying ATP/ADP ratios on P-II-P dephosphorylation was examined. From these studies, together with previous investigations, we conclude that P-II-P dephosphorylation specifically responds to changes in the levels of central metabolites of carbon metabolism, in particular 2-oxoglutarate.

Harvard Citation style: Forchhammer, K., Irmler, A., Kloft, N. and Ruppert, U. (2004) P_II signalling in unicellular cyanobacteria:: analysis of redox-signals and energy charge, Physiologia Plantarum, 120(1), pp. 51-56. https://doi.org/10.1111/j.0031-9317.2004.0218.x

APA Citation style: Forchhammer, K., Irmler, A., Kloft, N., & Ruppert, U. (2004). P_II signalling in unicellular cyanobacteria:: analysis of redox-signals and energy charge. Physiologia Plantarum. 120(1), 51-56. https://doi.org/10.1111/j.0031-9317.2004.0218.x