Crystal structure of a MarR family transcriptional regulator protein

Abstract

AbstractThe multiple antibiotic resistance regulator (MarR) family of transcription factor proteins form a large group of multitasking bio-molecules in pathogenicEscherichia coli(E. coli). HosA is one of these MarR transcription factors reported in dozens of pathogenicE. coliwith highly conserved sequence profiles. The HosA from the enteropathogenicE. coliO127:H6 (strain E2348/69), a predominantly monomeric protein, was overexpressed inE. coliand purified. The HosA protein crystals were obtained in microbatch under oil method at 4° C. The X-rays of the diffracted spots were extended to 2.21 Å resolution. The crystal belongs to the space groupP4322, with unit-cell parametersa= 67.16 Å,b= 67.16 Å,c= 95.66 Å and α = β = γ = 90°. In the asymmetric unit, monomeric HosA protein was crystallized and confirmed with the Matthew coefficient analysis (3.48 Å3Da-1). The monomeric structure is compared with previously solved structures of other homologous transcription factors. This confirmed the winged loop at the DNA binding region of the HosA protein.