The Klebsiella pneumoniae wabG gene:: Role in biosynthesis of the core lipopolysaccharide and virulence
The Klebsiella pneumoniae wabG gene:: Role in biosynthesis of the core lipopolysaccharide and virulence
复制标题
DOI：
10.1128/jb.185.24.7213-7221.2003
复制
发表时间：
2003-12-01
影响因子：
3.2
通讯作者：
Regué, M
中科院分区：
文献类型：
--
作者：
Izquierdo, L;Coderch, N;Regué, M
为了确定 wabG 基因在肺炎克雷伯菌核心脂多糖 (LPS) 生物合成中的功能，我们构建了 wabG 非极性突变体。对从野生型、突变株和互补突变体获得的 LPS 样品进行比较化学和结构分析获得的数据表明，wabG 基因参与在 α-D-吡喃半乳糖醛酸 (α-D-GalAp) 残基的 O-3 位点附着于 α-L-甘油-D-甘露-吡喃庚糖 II (L,D-HeppII)。肺炎克雷伯菌非极性wabG突变体缺乏细胞附着的荚膜多糖，但仍然能够产生荚膜多糖。肺炎克雷伯菌非极性 waaC 和 waaF 突变体也获得了类似的结果，它们产生比 wabG 突变体更短的 LPS 核心分子。 waa 基因簇中的其他外核肺炎克雷伯菌非极性突变体被封装。在不同的动物模型中进行测试时，肺炎克雷伯菌 waaC、waaF 和 wabG 突变体是无毒的。此外，这些突变体比野生型菌株对某些疏水化合物更敏感。所有这些特征都通过重新引入肺炎克雷伯菌的 waaC、waaF 和 wabG 基因而得到恢复。
To determine the function of the wabG gene in the biosynthesis of the core lipopolysaccharide (LPS) of Klebsiella pneumoniae, we constructed wabG nonpolar mutants. Data obtained from the comparative chemical and structural analysis of LPS samples obtained from the wild type, the mutant strain, and the complemented mutant demonstrated that the wabG gene is involved in attachment to alpha-L-glycero-D-manno-heptopyranose II (L,D-HeppII) at the O-3 position of an alpha-D-galactopyranosyluronic acid (alpha-D-GalAp) residue. K. pneumoniae nonpolar wabG mutants were devoid of the cell-attached capsular polysaccharide but were still able to produce capsular polysaccharide. Similar results were obtained with K. pneumoniae nonpolar waaC and waaF mutants, which produce shorter LPS core molecules than do wabG mutants. Other outer core K. pneumoniae nonpolar mutants in the waa gene cluster were encapsulated. K. pneumoniae waaC, waaF, and wabG mutants were avirulent when tested in different animal models. Furthermore, these mutants were more sensitive to some hydrophobic compounds than the wild-type strains. All these characteristics were rescued by reintroduction of the waaC, waaF, and wabG genes from K. pneumoniae.