Natural genetic exchange between Haemophilus and Neisseria:: Intergeneric transfer of chromosomal genes between major human pathogens
Natural genetic exchange between Haemophilus and Neisseria:: Intergeneric transfer of chromosomal genes between major human pathogens
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DOI：
10.1073/pnas.95.21.12381
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发表时间：
1998-10-13
影响因子：
11.1
通讯作者：
Langford, PR
中科院分区：
文献类型：
--
作者：
Kroll, JS;Wilks, KE;Langford, PR
嗜血杆菌属和奈瑟氏球菌属细菌家族的成员，通常定殖于鼻咽的重要人类病原体，天然地能够从其环境中摄取DNA。在每一个属中，这一过程通过DNA受体的序列特异性来区分其自身DNA和外来DNA。嗜血杆菌DNA摄取装置结合含有高度保守的9-bp核心序列的29-bp寡核苷酸结构域，而奈瑟球菌装置结合10-bp基序，每个基序（“摄取序列”，US）在相应属的染色体中高度过度呈现，特别是与形成基因终止子的反向对中的核心序列集中。在脑膜炎奈瑟氏菌（脑膜炎球菌）中意外地发现两个嗜血杆菌核心US形成sodC的终止子，并且序列分析强烈地表明，位于IS 1106旁边的该毒力基因通过从嗜血杆菌水平转移而产生。通过在基于计算机的基因组序列分析中使用US作为搜索字符串，确定了虽然“错误”属的US在奈瑟氏球菌或嗜血杆菌中不常见，但它们很可能标记已从嗜血杆菌转移的染色体DNA的结构域。在脑膜炎球菌染色体上发现了三个独立的嗜血杆菌样DNA结构域，分别与毒力基因sodC、生物基因簇和一个未知的ORF相关。本报告确定了属间转移的DNA及其在细菌中的来源，并进一步确定了异源染色体DNA转化作为在这些病原菌中建立潜在重要的染色体嵌合体的一种方式。
Members of the bacterial families Haemophilus and Neisseria, important human pathogens that commonly colonize the nasopharynx, are naturally competent for DNA uptake from their environment. In each genus this process is discriminant in favor of its own and against foreign DNA through sequence specificity of DNA receptors, The Haemophilus DNA uptake apparatus binds a 29-bp oligonucleotide domain containing a highly conserved 9-bp core sequence, whereas the neisserial apparatus binds a 10-bp motif, Each motif ("uptake sequence", US) is highly over-represented in the chromosome of the corresponding genus, particularly concentrated with core sequences in inverted pairs forming gene terminators. Two Haemophilus core USs were unexpectedly found forming the terminator of sodC in Neisseria meningitidis (meningococcus), and sequence analysis strongly suggests that this virulence gene, located next to IS1106, arose through horizontal transfer from Haemophilus. By using USs as search strings in a computer-based analysis of genome sequence, it was established that while USs of the "wrong" genus do not occur commonly in Neisseria or Haemophilus, where they do they are highly likely to flag domains of chromosomal DNA that have been transferred from Haemophilus. Three independent domains of Haemophilus-like DNA were found in the meningococcal chromosome, associated respectively with the virulence gene sodC, the bio gene cluster, and an unidentified orf. This report identifies inter-generically transferred DNA and its source in bacteria, and further identifies transformation with heterologous chromosomal DNA as a way of establishing potentially important chromosomal mosaicism in these pathogenic bacteria.