Analysis of Structure and function by the LysR-Type Transcriptional Regulator CbbR of Nostoc sp. PCC 7120

ABSTRACT The LysR-type Calvin–Benson–Bassham cycle transcriptional regulator CbbR plays an important role in CO 2 fixation in carbon metabolism in nature, which regulates the gene expression of the key enzyme RibisCO in the Calvin–Benson–Bassham (CBB) cycle. In this study, we optimized the conditions for the transformation, expression, and purification of CbbR in the model algae Nostoc sp. PCC 7120, obtained nick-DNA fragments that could tightly bind to CbbR_7120, and finally obtained CbbR protein crystals. These findings provide great assistance for the final crystallization of CbbR to solve the crystal structure of CbbR, and lay the foundation for understanding the mechanism of CO 2 fixation in the CBB cycle.