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A novel DNA-binding motif in MarA: the first structure for an AraC family transcriptional activator.

ABSTRACT: 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.

SUBMITTER: Rhee S

PROVIDER: S-EPMC27908 | biostudies-literature | 1998 Sep

REPOSITORIES: biostudies-literature

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A novel DNA-binding motif in MarA: the first structure for an AraC family transcriptional activator.

Rhee S S Martin R G RG Rosner J L JL Davies D R DR

Proceedings of the National Academy of Sciences of the United States of America 19980901 18

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 ...[more]

PMID: 9724717

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Comparative effects of overproducing the AraC-type transcriptional regulators MarA, SoxS, RarA and RamA on antimicrobial drug susceptibility in Klebsiella pneumoniae.

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