SurR: a transcriptional activator and repressor controlling hydrogen and elemental sulphur metabolism in Pyrococcus furiosus
This work describes the identification and characterization of SurR, Pyrococcus furiosus sulphur (S0) response regulator. SurR was captured from cell extract using promoter DNA of a hydrogenase operon that is downregulated in the primary response of P. furiosus to S0, as revealed by DNA microarray experiments. SurR was validated as a sequence-specific DNA binding protein, and characterization of the SurR DNA binding motif GTTn3AAC led to the identification of several target genes that contain an extended motif in their promoters. A number of these were validated to contain upstream SurR binding sites. These SurR targets strongly correspond with open reading frames and operons both up- and downregulated in the primary response to S0. In vitro transcription revealed that SurR is an activator for its own gene as well as for two hydrogenase operons whose expression is downregulated during the primary S0 response; it is also a repressor for two genes upregulated during the primary S0 response, one of which encodes the primary S0-reducing enzyme NAD(P)H sulphur reductase. Herein we give evidence for the role of SurR in both mediating the primary response to S0 and controlling hydrogen production in P. furiosus.
Document Type: Research Article
Affiliations: 1: Departments of Biochemistry and Molecular Biology and 2: Department of Microbiology, University of Regensburg, 93053 Regensburg, Germany. 3: Chemistry, University of Georgia, Athens, GA 30602, USA.
Publication date: January 1, 2009