Molecular mechanisms underlying allosteric behavior of Escherichia coli DgoR, a GntR/FadR family transcriptional regulator.

GntR/FadR family featuring an N-terminal winged helix-turn-helix DNA-binding domain and a C-terminal α-helical effector-binding and oligomerization domain constitutes one of the largest families of transcriptional regulators. Several GntR/FadR regulators govern the metabolism of sugar acids, carbon sources implicated in bacterial-host interactions. Although effectors are known for a few sugar acid regulators, the unavailability of relevant structures has left their allosteric mechanism unexplored.

D-galactonate metabolism in enteric bacteria: a molecular and physiological perspective.

D-galactonate, a widely prevalent sugar acid, was first reported as a nutrient source for enteric bacteria in the 1970s. Since then, decades of research enabled a description of the modified Entner-Doudoroff pathway involved in its degradation and reported the structural and biochemical features of its metabolic enzymes, primarily in Escherichia coli K-12. However, only in the last few years, the D-galactonate transporter has been characterized, and the regulation of the dgo operon, encoding the structural genes for the transporter and enzymes of D-galactonate metabolism, has been detailed.

Revisiting long-chain fatty acid metabolism in Escherichia coli: integration with stress responses.

Long-chain fatty acids (LCFAs) are a tremendous source of metabolic energy, an essential component of membranes, and important effector molecules that regulate a myriad of cellular processes. As an energy-rich nutrient source, the role of LCFAs in promoting bacterial survival and infectivity is well appreciated. LCFA degradation generates a large number of reduced cofactors that may confer redox stress; therefore, it is imperative to understand how bacteria deal with this paradoxical situation.

Metabolism of long-chain fatty acids affects disulfide bond formation in Escherichia coli and activates envelope stress response pathways as a combat strategy.

The envelope of gram-negative bacteria serves as the first line of defense against environmental insults. Therefore, its integrity is continuously monitored and maintained by several envelope stress response (ESR) systems. Due to its oxidizing environment, the envelope represents an important site for disulfide bond formation.

Molecular insights into effector binding by DgoR, a GntR/FadR family transcriptional repressor of D-galactonate metabolism in Escherichia coli.

Several GntR/FadR transcriptional regulators govern sugar acid metabolism in bacteria. Although effectors have been identified for a few sugar acid regulators, the mode of effector binding is unknown. Even in the overall FadR subfamily, there are limited details on effector-regulator interactions.