Mutations and rearrangements in the genome of Sulfolobus solfataticus P2
Mutations and rearrangements in the genome of Sulfolobus solfataticus P2
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DOI：
10.1128/jb.00061-06
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发表时间：
2006-06-01
影响因子：
3.2
通讯作者：
Garrett, Roger A.
中科院分区：
文献类型：
--
作者：
Redder, Peter;Garrett, Roger A.
硫磺硫化叶菌P2的基因组比任何其他来自古细菌或细菌的测序基因组携带更多数量的转座因子，因此，可能特别容易发生重排和变化。为了更深入地了解基因组中可能发生的不同类型突变和可能的重排的性质和频率，检查了pyrEF基因座中用5-氟乳清酸选择后分离的突变。130个突变中约有三分之二是由移动的元件插入引起的，包括插入序列（IS）元件和单个非自主移动的元件SM 2。对于这些中的每一个，元件被鉴定并显示存在于其原始基因组位置，与移动的元件的拷贝数的逐渐增加一致。此外，观察到几个碱基对替换，以及小的缺失，插入和重复，约五分之一的突变发生在基因组的其他地方，可能在乳清酸转运蛋白基因。一个突变体表现出5-kb的基因组重排的pyrEF位点涉及两步IS元件依赖性反应，其边界被定义使用一个专门开发的“体外库”的战略。此外，在寻找供体移动的元件时，发现了在菌株P2的基因组中发生的两个主要变化的证据，一个构成了总基因组（124 kb）的约4%的单一缺失，而另一个涉及25 kb区域的倒位。两者都与IS元件接壤，并被推断为通过重组事件而产生。这些结果强调了在用诸如S.基因组不断变化的太阳鱼
The genome of Sulfolobus solfataricus P2 carries a larger number of transposable elements than any other sequenced genome from an archaeon or bacterium and, as a consequence, may be particularly susceptible to rearrangement and change. In order to gain more insight into the natures and frequencies of different types of mutation and possible rearrangements that can occur in the genome, the pyrEF locus was examined for mutations that were isolated after selection with 5-fluoroorotic acid. About two-thirds of the 130 mutations resulted from insertions of mobile elements, including insertion sequence (IS) elements and a single nonautonomous mobile element, SM2. For each of these, the element was identified and shown to be present at its original genomic position, consistent with a progressive increase in the copy numbers of the mobile elements. In addition, several base pair substitutions, as well as small deletions, insertions, and a duplication, were observed, and about one-fifth of the mutations occurred elsewhere in the genome, possibly in an orotate transporter gene. One mutant exhibited a 5-kb genomic rearrangement at the pyrEF locus involving a two-step IS element-dependent reaction, and its boundaries were defined using a specially developed "in vitro library" strategy. Moreover, while searching for the donor mobile elements, evidence was found for two major changes that had occurred in the genome of strain P2, one constituting a single deletion of about 4% of the total genome (124 kb), while the other involved the inversion of a 25-kb region. Both were bordered by IS elements and were inferred to have arisen through recombination events. The results underline the caution required in working experimentally with an organism such as S. solfataricus with a continually changing genome.