Twenty-eight divergent polysaccharide loci specifying within- and amongst-strain capsule diversity in three strains of Bacteroides fragilis.
Twenty-eight divergent polysaccharide loci specifying within- and amongst-strain capsule diversity in three strains of Bacteroides fragilis.
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DOI：
10.1099/mic.0.042978-0
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发表时间：
2010-11
期刊：
影响因子：
--
通讯作者：
Parkhill J
中科院分区：
文献类型：
--
作者：
Patrick S;Blakely GW;Houston S;Moore J;Abratt VR;Bertalan M;Cerdeño-Tárraga AM;Quail MA;Corton N;Corton C;Bignell A;Barron A;Clark L;Bentley SD;Parkhill J
将最初在美国分离的脆弱拟杆菌638 R的全基因组序列与在英国（NCTC 9343）和日本（YCH 46）分离的两种先前测序的菌株进行比较。10个位点含有与多糖（PS）生物合成相关的基因，每个位点包括一个假定的Wzx翻转酶和Wzy聚合酶的存在下，在所有三个菌株中得到证实，尽管NCTC 9343和638 R表面PS特异性抗体之间缺乏交叉反应性，通过免疫标记和显微镜。基因组比较显示PS生物合成位点多样性的特殊水平。在每个菌株中明显的10个不同的PS相关位点中，NCTC 9343和638R之间没有相似的。YCH 46与NCTC 9343共享一个基因座，通过mAb标记确认，并且与638R共享第二个不同的基因座，使得三个菌株之间总共有28个不同的PS生物合成基因座。在NCTC 9343中观察到的菌株638 R中缺乏相位可变大胶囊（LC）表达，可能是由于在推定的起始糖基转移酶内产生终止密码子的点突变，这是NCTC 9343中LC表达所必需的。观察到其他主要序列差异来自不同数量和种类的插入的染色体外元件，特别是原噬菌体。广泛的水平基因转移已发生在这些菌株中，尽管存在大量的不同的DNA限制和修饰系统，以防止收购外来DNA。PS生物合成基因座的耐高温菌株多样性水平是前所未有的。
Comparison of the complete genome sequence of Bacteroides fragilis 638R, originally isolated in the USA, was made with two previously sequenced strains isolated in the UK (NCTC 9343) and Japan (YCH46). The presence of 10 loci containing genes associated with polysaccharide (PS) biosynthesis, each including a putative Wzx flippase and Wzy polymerase, was confirmed in all three strains, despite a lack of cross-reactivity between NCTC 9343 and 638R surface PS-specific antibodies by immunolabelling and microscopy. Genomic comparisons revealed an exceptional level of PS biosynthesis locus diversity. Of the 10 divergent PS-associated loci apparent in each strain, none is similar between NCTC 9343 and 638R. YCH46 shares one locus with NCTC 9343, confirmed by mAb labelling, and a second different locus with 638R, making a total of 28 divergent PS biosynthesis loci amongst the three strains. The lack of expression of the phase-variable large capsule (LC) in strain 638R, observed in NCTC 9343, is likely to be due to a point mutation that generates a stop codon within a putative initiating glycosyltransferase, necessary for the expression of the LC in NCTC 9343. Other major sequence differences were observed to arise from different numbers and variety of inserted extra-chromosomal elements, in particular prophages. Extensive horizontal gene transfer has occurred within these strains, despite the presence of a significant number of divergent DNA restriction and modification systems that act to prevent acquisition of foreign DNA. The level of amongst-strain diversity in PS biosynthesis loci is unprecedented.
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影响因子：
64.8
作者：
通讯作者：
--
影响因子：
3
作者：
LUTTON, DA;PATRICK, S;MCNEILL, TA
通讯作者：
MCNEILL, TA
影响因子：
6.4
作者：
PRIVITERA, G;DUBLANCHET, A;SEBALD, M
通讯作者：
SEBALD, M
影响因子：
14.9
作者：
McMahon SA;Roberts GA;Johnson KA;Cooper LP;Liu H;White JH;Carter LG;Sanghvi B;Oke M;Walkinshaw MD;Blakely GW;Naismith JH;Dryden DT
通讯作者：
Dryden DT
影响因子：
9.4
作者：
Katsandri, Anastasia;Papaparaskevas, Joseph;Avlamis, Athina
通讯作者：
Avlamis, Athina