A wide variety of bacterial pathogens express phase-variable DNA methyltransferases that control expression of multiple genes via epigenetic mechanisms. These randomly switching regulons – phasevarions – regulate genes involved in pathogenesis, host adaptation, and antibiotic resistance. Individual phase-variable genes can be identified in silico as they contain easily recognized features such as simple sequence repeats (SSRs) or inverted repeats (IRs) that mediate the random switching of expression. Conversely, phasevarion-controlled genes do not contain any easily identifiable features. The study of DNA methyltransferase specificity using Single-Molecule, Real-Time (SMRT) sequencing and methylome analysis has rapidly advanced the analysis of phasevarions by allowing methylomics to be combined with whole-transcriptome/proteome analysis to comprehensively characterize these systems in a number of important bacterial pathogens.

各种各样的细菌病原体表达通过表观遗传机制控制多个基因表达的相变DNA甲基转移酶。这些随机切换的调节子-相变-调节与发病机制，宿主适应性和抗生素抗性有关的基因。可以通过计算机识别单个相变基因因为它们包含容易识别的特征，例如介导表达随机转换的简单序列重复（SSR）或反向重复（IR）。相反，相变控制的基因不包含任何容易识别的特征。通过使用单分子实时（SMRT）测序和甲基化组分析对DNA甲基转移酶特异性进行的研究，通过将甲基化组学与全转录组/蛋白质组分析相结合以全面表征许多系统中的这些系统，已快速推进了相变分析。重要的细菌病原体。