Excision of IS492 requires flanking target sequences and results in circle formation in Pseudoalteromonas atlantica.
Excision of IS492 requires flanking target sequences and results in circle formation in Pseudoalteromonas atlantica.
复制标题
IS492 的切除需要侧翼靶序列并导致大西洋假交替单胞菌中环的形成。
DOI：
10.1128/jb.181.16.4937-4948.1999
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发表时间：
1999
影响因子：
3.2
通讯作者：
Glasgow,AC
中科院分区：
文献类型：
--
作者：
Perkins-Balding,D;Duval-Valentin,G;Glasgow,AC
革兰氏阴性海洋细菌大西洋假交替单胞菌（Pseudoalteromonasatlantica）产生胞外多糖（EPS），该胞外多糖在该细菌的生物膜形成中是重要的。在胞外多糖（eps）产生所必需的位点插入和精确切除IS 492，控制了P中EPS产生的时相变化。大西洋号。检测P. atlanticaby使用基于PCR的分析揭示了IS 492的环状形式，其可能是转座的中间体或切除的末端产物。IS 492环连接的DNA序列表明，该元件的末端与5-bp间隔序列并置。该间隔区序列对应于在P上所有IS 492插入位点处发现的染色体靶序列的5-bp重复。我们用反向PCR鉴定了大西洋染色体。IS 492环的形成与从P.当将大肠杆菌质粒导入大肠杆菌时，对IS 492插入位点两侧宿主序列的缺失分析表明，5-bp重复的靶序列对IS 492的精确切除和E.杆菌切除IS 492 inE。大肠杆菌的表达水平也取决于推定的转座酶MooV的表达水平。通过在环状连接处连接插入序列元件的末端，产生一个新的强启动子来表达mooV，这表明环状形式的IS 492具有调节作用。
The gram-negative marine bacteriumPseudoalteromonas atlanticaproduces extracellular polysaccharide (EPS) that is important in biofilm formation by this bacterium. Insertion and precise excision of IS492at a locus essential for extracellular polysaccharide production (eps) controls phase variation of EPS production inP. atlantica. Examination of IS492transposition inP. atlanticaby using a PCR-based assay revealed a circular form of IS492that may be an intermediate in transposition or a terminal product of excision. The DNA sequence of the IS492circle junction indicates that the ends of the element are juxtaposed with a 5-bp spacer sequence. This spacer sequence corresponds to the 5-bp duplication of the chromosomal target sequence found at all IS492insertion sites on theP. atlanticachromosome that we identified by using inverse PCR. IS492circle formation correlated with precise excision of IS492from theP. atlantica epstarget sequence when introduced intoEscherichia colion a plasmid. Deletion analyses of the flanking host sequences at theepsinsertion site for IS492demonstrated that the 5-bp duplicated target sequence is essential for precise excision of IS492and circle formation inE. coli. Excision of IS492inE. colialso depends on the level of expression of the putative transposase, MooV. A regulatory role for the circular form of IS492is suggested by the creation of a new strong promoter for expression ofmooVby the joining of the ends of the insertion sequence element at the circle junction.