Srikhanta Yogitha N, Maguire Tina L, Stacey Katryn J, Grimmond Sean M, Jennings Michael P
School of Molecular and Microbial Science and Institute for Molecular Bioscience, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
Proc Natl Acad Sci U S A. 2005 Apr 12;102(15):5547-51. doi: 10.1073/pnas.0501169102. Epub 2005 Mar 31.
Several host-adapted bacterial pathogens contain methyltransferases associated with type III restriction-modification (R-M) systems that are subject to reversible, high-frequency on/off switching of expression (phase variation). To investigate the role of phase-variable expression of R-M systems, we made a mutant strain lacking the methyltransferase (mod) associated with a type III R-M system of Haemophilus influenzae and analyzed its phenotype. By microarray analysis, we identified a number of genes that were either up- or down-regulated in the mod mutant strain. This system reports the coordinated random switching of a set of genes in a bacterial pathogen and may represent a widely used mechanism.
几种宿主适应性细菌病原体含有与III型限制修饰（R-M）系统相关的甲基转移酶，这些系统的表达会发生可逆的高频开/关切换（相变）。为了研究R-M系统相变表达的作用，我们构建了一个缺乏与流感嗜血杆菌III型R-M系统相关的甲基转移酶（mod）的突变菌株，并分析了其表型。通过微阵列分析，我们鉴定出了一些在mod突变菌株中上调或下调的基因。该系统揭示了细菌病原体中一组基因的协同随机切换，可能代表了一种广泛使用的机制。
