Molecular characterization of the Pseudomonas aeruginosa serotype O5 (PAO1) B-band lipopolysaccharide gene cluster
Molecular characterization of the Pseudomonas aeruginosa serotype O5 (PAO1) B-band lipopolysaccharide gene cluster
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DOI：
10.1046/j.1365-2958.1996.1351503.x
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发表时间：
1996-11-01
影响因子：
3.6
通讯作者：
Lam, JS
中科院分区：
文献类型：
--
作者：
Burrows, LL;Charter, DF;Lam, JS
铜绿假单胞菌（Pseudomonas aeruginosa）共表达鼠李糖的均聚物a带脂多糖（LPS）和具有2-5个重复糖的异聚物b带脂多糖（LPS），这是血清型特异性抗原。先前已经克隆了P. aeroginosa O5（菌株PAO1）的a带和b带生物合成基因簇，本文报道了b带o抗原生物合成基因簇的DNA序列和分子分析。鉴定出16个被认为参与O5 O抗原合成的开放阅读框（orf），包括wzz（rol）、wry（rfc）和wbpA-wbpN，另外鉴定出3个被认为与LPS合成无关的orf （hisH、hisF和uvrB）。大多数wbp基因仅存在于O2、O5、O16、O18和O20血清型中，它们形成了化学上和结构上相关的o抗原血清群。相比之下，wbpM和wbpN在所有20种血清型铜绿假单胞菌中都是常见的，尽管wbpM不是血清组特异性的，但敲除突变证实了它是O5 o抗原生物合成所必需的。一个新的插入序列IS 1209存在于血清群特异性和非特异性区域之间的连接处，我们根据其与数据库中的同源性预测了wbp簇中编码的蛋白质的功能，并提出了P. aeruginosa O5 o抗原生物合成的途径。
Pseudomonas aeruginosa co-expresses A-band lipopolysaccharide (LPS), a homopolymer of rhamnose, and B-band LPS, a heteropolymer with a repeating unit of 2-5 sugars which is the serotype-specific antigen, The gene clusters for A- and B-band biosynthesis in P. aeroginosa O5 (strain PAO1) have been cloned previously, Here we report the DNA sequence and molecular analysis of the B-band O-antigen biosynthetic cluster. Sixteen open reading frames (ORFs) thought to be involved in synthesis of the O5 O antigen were identified, including wzz(rol), wry(rfc), and wbpA-wbpN, A further 3 ORFs not thought to be involved with LPS synthesis were identified (hisH, hisF, and uvrB). Most of the wbp genes are found only in serotypes O2, O5, O16, O18, and O20, which form a chemically and structurally related O-antigen serogroup. In contrast, wbpM and wbpN are common to all 20 serotypes of P. aeruginosa, Although wbpM is not serogroup-specific, knockout mutations confirmed it is necessary for O5 O-antigen biosynthesis. A novel insertion sequence, IS 1209 is present at the junction between the serogroup-specific and non-specific regions, We have predicted the functions of the proteins encoded in the wbp cluster based on their homologies to those in the databases, and provide a proposed pathway of P. aeruginosa O5 O-antigen biosynthesis.