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

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.

Source: Acta Crystallographica Section F - August 1, 2018 Category: Biochemistry Authors: Mahounga, D.M. Sun, H. Jiang, Y.-L. Tags: crystal structure LysR-type transcription factors cyanobacteria Synechococcus elongatus PCC 7942 CmpR-EBD complex with ribulose 1,5-bisphosphate CO2-concentrating mechanism research communications Source Type: research