A novel DNA-binding motif in MarA: the first structure for an AraC family transcriptional activator.
A crystal structure for a member of the AraC prokaryotic transcriptional activator family, MarA, in complex with its cognate DNA-binding site is described. MarA consists of two similar subdomains, each containing a helix-turn-helix DNA-binding motif. The two recognition helices of the motifs are inserted into adjacent major groove segments on the same face of the DNA but are separated by only 27 A thereby bending the DNA by approximately 35 degrees. Extensive interactions between the recognition helices and the DNA major groove provide the sequence specificity.
Rhee
S
S
Laboratory of Molecular Biology, National Institutes of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0560, USA.
Martin
R G
RG
Rosner
J L
JL
Davies
D R
DR
D000595:Amino Acid Sequence; D051777:AraC Transcription Factor; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006860:Hydrogen Bonding; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012097:Repressor Proteins / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators / Q000737:chemistry / Q000378:metabolism*; D014157:Transcription Factors
D051777:AraC Transcription Factor; C497371:AraC protein, E coli; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C080002:MarA protein, E coli; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D004247:DNA