Wei et al. Biotechnol Biofuels (2016) 9:264 DOI 10.1186/s13068-016-0679-7
Biotechnology for Biofuels Open Access
RESEARCH
Succinate production positively correlates with the affinity of the global transcription factor Cra for its effector FBP in Escherichia coli Li‑Na Wei†, Li‑Wen Zhu† and Ya‑Jie Tang*
Abstract Background: Effector binding is important for transcription factors, affecting both the pattern and function of tran‑ scriptional regulation to alter cell phenotype. Our previous work suggested that the affinity of the global transcription factor catabolite repressor/activator (Cra) for its effector fructose-1,6-bisphosphate (FBP) may contribute to succinate biosynthesis. To support this hypothesis, single-point and three-point mutations were proposed through the semirational design of Cra to improve its affinity for FBP. Results: For the first time, a positive correlation between succinate production and the affinity of Cra for FBP was revealed in Escherichia coli. Using the best-fit regression function, a cubic equation was used to examine and describe the relationship between succinate production and the affinity of Cra for FBP, demonstrating a significant positive correlation between the two factors (coefficient of determination R2 = 0.894, P = 0.000
