TY  - JOUR
A1  - Guljamow, Arthur
A1  - Barchewitz, Tino
A1  - Große, Rebecca
A1  - Timm, Stefan
A1  - Hagemann, Martin
A1  - Dittmann, Elke
T1  - Diel Variations of Extracellular Microcystin Influence the
Subcellular Dynamics of RubisCO in Microcystis aeruginosa
PCC 7806
T2  - Microorganisms : open access journal
N2  - The ubiquitous freshwater cyanobacterium Microcystis is remarkably successful, showing a high tolerance against fluctuations in environmental conditions. It frequently forms dense blooms which can accumulate significant amounts of the hepatotoxin microcystin, which plays an extracellular role as an infochemical but also acts intracellularly by interacting with proteins of the carbon metabolism, notably with the CO2 fixing enzyme RubisCO. Here we demonstrate a direct link between external microcystin and its intracellular targets. Monitoring liquid cultures of Microcystis in a diel experiment revealed fluctuations in the extracellular microcystin content that correlate with an increase in the binding of microcystin to intracellular proteins. Concomitantly, reversible relocation of RubisCO from the cytoplasm to the cell’s periphery was observed. These variations in RubisCO localization were especially pronounced with cultures grown at higher cell densities. We replicated these effects by adding microcystin externally to cultures grown under continuous light. Thus, we propose that microcystin may be part of a fast response to conditions of high light and low carbon that contribute to the metabolic flexibility and the success of Microcystis in the field.
KW  - cyanobacterial bloom
KW  - Microcystis
KW  - microcystin
KW  - RubisCO
KW  - extracellular signaling
Y1  - 2021
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/52127
SN  - 2076-2607
VL  - 9
IS  - 6
PB  - MDPI
CY  - Basel
ER  -