tailieunhanh - Báo cáo khoa học: Structure of FocB – a member of a family of transcription factors regulating fimbrial adhesin expression in uropathogenic Escherichia coli

In uropathogenic Escherichia coli, UPEC, different types of fimbriae are expressed to mediate interactions with host tissue. FocB belongs to the PapB family of transcription factors involved in the regulation of fimbriae gene clusters. Recent findings suggest that members from this family of proteins may form homomeric or heteromeric complexes and exert both positive and negative effects on the transcription of fimbriae genes. | Structure of FocB - a member of a family of transcription factors regulating fimbrial adhesin expression in uropathogenic Escherichia coli Ulrika W. Hultdin1 Stina Lindberg2 Christin Grundstrom1 Shenghua Huang1 Bernt Eric Uhlin2 and A. Elisabeth Sauer-Eriksson1 1 Department of Chemistry Umea University Sweden 2 Department of Molecular Biology The Laboratory for Molecular Infection Medicine Sweden MIMS Umea University Sweden Keywords fimbriae FocB repressor protein uropathogenic Escherichia coli X-ray crystallography Correspondence A. E. Sauer-Eriksson or B. E. Uhlin Department of Chemistry Umea University SE-90187 Umea Sweden Department of Molecular Biology Laboratory for Molecular Infection Medicine Sweden MIMS Umea University SE-901 87 Umea Sweden Fax 4690 7865944 4690 772630 Tel 4690 7865923 4690 7856731 E-mail Database The atomic coordinates and structure factors for the Escherichia coli FocB protein are available in the Protein Data Bank database under the accession number 3M8J Received 28 January 2010 revised 5 May 2010 accepted 17 June 2010 In uropathogenic Escherichia coli UPEC different types of fimbriae are expressed to mediate interactions with host tissue. FocB belongs to the PapB family of transcription factors involved in the regulation of fimbriae gene clusters. Recent findings suggest that members from this family of proteins may form homomeric or heteromeric complexes and exert both positive and negative effects on the transcription of fimbriae genes. To elucidate the detailed function of FocB we have determined its crystal structure at A resolution. FocB is an all a-helical protein with a helixturn-helix motif. Interestingly conserved residues important for DNA-binding are located not in the postulated recognition helix of the motif but in the preceding helix. Results from protein-DNA-binding studies suggest that FocB interacts with the minor groove of its cognate DNA target