C 5: Proteolytic degradation by FtsH proteases as regulatory mechanism of stress acclimatisation in cyanobacteria

Prof. Dr. Reinhard Krämer

Institut für Biochemie, Universität zu Köln
email: r.kraemer@uni-koeln.de
phone: +49-(0)221 470 6461
website

Dr. Kay Marin

Institut für Biochemie, Universität zu Köln
email: kay.marin@uni-koeln.de
phone: +49-(0)221 470 6476
website

Running time: 2007 – 2011

Abstract

In the cyanobacterial model strain Synechocystis sp. PCC 6803 the accumulation of the chemical chaperone glucosylglycerol (GG) is crucial for maintenance of turgor and cellular growth under osmotic stress conditions. Regulation of GG synthesis comprises posttranslational modification and subsequent degradation of the key enzyme of GG synthesis by a membrane bound FtsH protease. In this project the physiological role of AAA-proteases in stress response of Synechocystis will be studied. We focus on the molecular mechanism of substrate recognition by FtsH proteases, which will be analysed in vivo as well as in vitro.

(A final report will follow.)

Publications resulting from the project:

Novak, J.F., Stirnberg, M., Roenneke, B., Marin, K. (2010). A novel mechanism of osmosensing: A salt dependent protein-nucleic acid interaction in the cyanobacterium Synechocystis sp. PCC 6803. J Biol Chem. 286, 3235-41.

Drath, M., Kloft, N., Batschauer, A., Marin, K., Novak, J., Forchhammer, K. (2008). Ammonia triggers photodamage of photosystem II in the Cyanobacterium Synechocystis sp. strain PCC 6803. Plant Physiol. 147, 206.