Open AccessPreliminary crystallographic analysis of the Escherichia coli antitoxin MqsA (YgiT/b3021) in complex with mqsRA promoter DNA
Author(s) -
Brown Breann L.,
Page Rebecca
Publication year - 2010
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309110028617
Subject(s) - antitoxin , escherichia coli , dna , duplex (building) , palindromic sequence , transcription (linguistics) , crystallography , palindrome , biology , chemistry , microbiology and biotechnology , genetics , toxin , gene , genome , philosophy , linguistics
The Escherichia coli proteins MqsR and MqsA comprise a novel toxin–antitoxin (TA) system. MqsA, the antitoxin, defines a new family of antitoxins because unlike other antitoxins MqsA is structured throughout its entire sequence, binds zinc and coordinates DNA via its C‐terminal and not its N‐terminal domain. In order to understand how bacterial antitoxins, and MqsA in particular, regulate transcription, the MqsA protein was cocrystallized with a 26‐mer duplex DNA corresponding to the palindromic region of the mqsRA promoter. The merohedrally twinned crystal belonged to space group P 4 1 , with unit‐cell parameters a = 60.99, b = 60.99, c = 148.60 Å. A complete data set was collected to a resolution of 2.1 Å. The solvent content of the crystal was consistent with the presence of two MqsA molecules bound to the duplex DNA in the asymmetric unit.