1j5y

Protein Summary

This protein is proposed to contain a 3-histidine (3H) domain, named after its three highly conserved histidines, and a DNA-binding domain. It represents the first structure of a 3H protein family member. Based on sequence analysis, its function has been postulated to involve binding of small molecules. Recent experimental data support this prediction, suggesting that it belongs to a family of de novo NAD synthesis pathway regulators that may bind to nicotinamide, nicotinic acid, or other substrate/products. When activated by these small molecules, it is proposed to bind to the NAD promoter region to repress the de novo NAD biosynthesis operon. This pathway has been well characterized in the TM1602 homologous protein, yrxA, from Bacillus subtilis. Experimental characterization of this protein is now in progress [Rodionov & Osterman].[Ref]

Ligand Summary