tailieunhanh - Báo cáo y học: "Genomic transcriptional response to loss of chromosomal supercoiling in Escherichia coli"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Genomic transcriptional response to loss of chromosomal supercoiling in Escherichia coli. | Research Open Access Genomic transcriptional response to loss of chromosomal supercoiling in Escherichia coli Brian J Peter Javier Arsuaga Adam M Breier Arkady B Khodursky Patrick O Brown and Nicholas R Cozzarelli Addresses Department of Molecular and Cell Biology University of California Berkeley CA 94720-3204 USA. Mathematics Department University of California Berkeley CA 94720 USA. Graduate Group in Biophysics University of California Berkeley CA 94720 USA. Department of Biochemistry Molecular Biology and Biophysics University of Minnesota St. Paul MN 55108 USA. Department of Biochemistry and Howard Hughes Medical Institute Stanford University Stanford CA 94305-5307 USA. Current address Neurobiology Division MRC Laboratory of Molecular Biology Cambridge CB2 2QH UK. Correspondence Nicholas RCozzarelli. E-mail ncozzare@ Published I November 2004 Genome Biology 2004 5 R87 The electronic version of this article is the complete one and can be found online at http 2004 5 11 R87 Received 11 August 2004 Revised 1 October 2004 Accepted 11 October 2004 2004 Peter et al. licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background The chromosome of Escherichia coli is maintained in a negatively supercoiled state and supercoiling levels are affected by growth phase and a variety of environmental stimuli. In turn supercoiling influences local DNA structure and can affect gene expression. We used microarrays representing nearly the entire genome of Escherichia coli MG1655 to examine the dynamics of chromosome structure. Results We measured the transcriptional response to a loss of supercoiling caused either by genetic impairment of a topoisomerase or addition of specific topoisomerase .