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Crystal structure of the effector-binding domain of Synechococcus elongatus CmpR in complex with ribulose 1,5-bisphosphate.

ABSTRACT: The CO2-concentrating mechanism (CCM) has evolved to improve the efficiency of photosynthesis in autotrophic cyanobacteria. CmpR, a LysR-type transcriptional regulator (LTTR) from Synechococcus elongatus PCC 7942, was found to regulate CCM-related genes under low-CO2 conditions. Here, the dimeric structure of the effector-binding domain of CmpR (CmpR-EBD) in complex with the co-activator ribulose 1,5-bisphosphate (RuBP) is reported at 2.15?Å resolution. One RuBP molecule binds to the inter-domain cleft between the two subunits of the CmpR-EBD dimer. Structural comparison combined with sequence analyses demonstrated that CmpR-EBD has an overall structure similar to those of LTTRs of known structure, but possesses a distinctly different effector-binding pattern.

SUBMITTER: Mahounga DM

PROVIDER: S-EPMC6096476 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Crystal structure of the effector-binding domain of Synechococcus elongatus CmpR in complex with ribulose 1,5-bisphosphate.

Mahounga Didel M DM Sun Hui H Jiang Yong Liang YL

Acta crystallographica. Section F, Structural biology communications 20180801 Pt 8

The CO2-concentrating mechanism (CCM) has evolved to improve the efficiency of photosynthesis in autotrophic cyanobacteria. CmpR, a LysR-type transcriptional regulator (LTTR) from Synechococcus elongatus PCC 7942, was found to regulate CCM-related genes under low-CO2 conditions. Here, the dimeric structure of the effector-binding domain of CmpR (CmpR-EBD) in complex with the co-activator ribulose 1,5-bisphosphate (RuBP) is reported at 2.15 Å resolution. One RuBP molecule bi ...[more]

PMID: 30084400

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Unusual ribulose 1,5-bisphosphate carboxylase/oxygenase of anoxic Archaea.

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