IS231-MIC231 elements from Bacillus cereus sensu lato are modular
IS231-MIC231 elements from Bacillus cereus sensu lato are modular
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DOI：
10.1111/j.1365-2958.2004.04146.x
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发表时间：
2004-07-01
影响因子：
3.6
通讯作者：
Mahillon, J
中科院分区：
文献类型：
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作者：
De Palmenaer, D;Vermeiren, C;Mahillon, J
IS231A最初是在苏云金芽孢杆菌中发现的，是一个典型的1.6 kb插入序列（IS），在转座酶基因两侧显示20 bp的反向重复序列（IR）。这种典型组织的第一个主要变异是在MIC231A1中发现的。这个移动插入盒（MIC），由is231a相关的肢体描绘，含有一个活性的d立体特异性内肽酶（adp）基因而不是转座酶。有趣的是，研究表明MIC231A1可以通过IS231A转座酶进行反式动员。在本文中，我们证明了IS231-MIC231元素家族可以扩展到广泛的相关实体，显示出更高水平的结构复杂性。几个is231a样元件在其转座酶基因上游含有编码推定的抗生素耐药性或调节因子的乘客基因。此外，MIC231元件的多样性范围从空盒到携带多达三个客运基因的结构。其中，MIC231V除了携带一个adp基因外，还携带一个活性磷霉素耐药决定因素。体内转座实验表明MIC231V也被IS231A转座酶反式激活。这些结果进一步支持了这些模块化移动元件对蜡样芽孢杆菌/B基因组可塑性的潜在贡献。基因。
IS231A was originally discovered in Bacillus thuringiensis as a typical 1.6 kb insertion sequence (IS) displaying 20 bp inverted repeats (IR) flanking a transposase gene. A first major variation of this canonical organization was found in MIC231A1. This mobile insertion cassette (MIC), delineated by IS231A-related extremities, contained an active D-stereospecific endopeptidase (adp) gene instead of a transposase. Interestingly, it was shown that MIC231A1 can be mobilized in trans by the IS231A transposase. In this paper, we show that this family of IS231-MIC231 elements can be extended to a broad range of related entities displaying higher levels of structural complexity. Several IS231A-like elements contained, upstream of their transposase gene, passenger genes coding for putative antibiotic resistances or regulatory factors. Furthermore, the diversity of the MIC231 elements ranged from empty cassettes to structures carrying up to three passenger genes. Among these, MIC231V carried, in addition to an adp gene, an active fosfomycin resistance determinant. In vivo transposition assays showed that MIC231V is also trans-activated by the IS231A transposase. These results lend further support to the potential contribution of these modular mobile elements to the genome plasticity of the Bacillus cereus/B. thuringiensis group.