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Updated: Aug 14, 2026

Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis
Published on: September 11, 2018
The SigB sigma factor mediates high-temperature responses in the cyanobacterium Synechocystis sp. PCC6803
Ilona Tuominen1, Maija Pollari, Esa Tyystjärvi
1Plant Physiology and Molecular Biology, Department of Biology, University of Turku, FI-20014 Turku, Finland.
Abstract:
The sigma factors of RNA polymerase play central roles when bacteria adapt to different environmental conditions. We studied heat-shock responses in the cyanobacterium Synechocystis sp. PCC6803 using the sigma factor inactivation strains deltasigB, deltasigD and deltasigBD. The SigB factor was found to be important for short-term heat-shock responses and acquired thermotolerance. The normal high-temperature induction of the hspA gene depended on the SigB factor. The SigD sigma factor had a role in high-temperature responses as well, and the double inactivation strain deltasigBD grew more slowly at 43 degrees C than the deltasigB and deltasigD strains.
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