Dudas K C, Apicella M A
Department of Medicine, School of Medicine, State University of New York at Buffalo 14215.
Infect Immun. 1988 Feb;56(2):499-504. doi: 10.1128/iai.56.2.499-504.1988.
The identification of enterobacterial mutants that contain alterations in the lipopolysaccharide (LPS) oligosaccharide core structure facilitated the development of the model of the physicochemical and immunochemical structures of enteric LPS. Results of recent immunochemical studies have suggested that the structural model of the lipooligosaccharides (LOSs) of Neisseria gonorrhoeae may differ from the enteric LPS model. The difficulties in the analysis of the wild-type gonococcal LOS have precluded understanding of the precise nature of the LOS structure. This study was undertaken to isolate a series of mutants of N. gonorrhoeae 1291 that had sequential saccharide deletions in the LOS. Results of preliminary studies suggested that the pyocin, designated pyocin C, allowed selection of gonococci with such mutant LOS structures. Results also indicated that the receptor for pyocin C binding was an LOS component. Pyocin C selection led to the isolation of five strains with LOS patterns on sodium dodecyl sulfate-polyacrylamide gels which differed from the LOS of parent strain 1291. In this system, the Mr of the parent LOS was 4,715, while the LOSs from the mutant strains demonstrated progressive saccharide deletions, with Mrs of 4,230, 4,089, 3,627, 3,262, and 3,197. Protein patterns of these mutants on sodium dodecyl sulfate-polyacrylamide gels were qualitatively similar to those of the parent strains. Results of studies with five monoclonal antibodies specific for neisserial LOS indicated that shared as well as unique epitopes were present on the mutant LOSs. Results of ketodeoxyoctonate analysis of the mutant LOSs indicated that the majority of the ketodeoxyoctonate residues may be substituted on C-4 or C-5. Chemical and immunological analysis of such LOS mutants should expedite the development of the model for the structure of gonococcal LOS.
对脂多糖（LPS）寡糖核心结构发生改变的肠杆菌突变体的鉴定，推动了肠道LPS物理化学和免疫化学结构模型的发展。近期免疫化学研究结果表明，淋病奈瑟菌脂寡糖（LOS）的结构模型可能与肠道LPS模型不同。野生型淋球菌LOS分析的困难阻碍了对LOS结构确切性质的理解。本研究旨在分离一系列淋病奈瑟菌1291的突变体，这些突变体的LOS中存在连续的糖类缺失。初步研究结果表明，名为pyocin C的绿脓菌素可用于筛选具有此类突变LOS结构的淋球菌。结果还表明，pyocin C结合的受体是一种LOS成分。通过pyocin C筛选，分离出了五株在十二烷基硫酸钠-聚丙烯酰胺凝胶上LOS图谱与亲本菌株1291不同的菌株。在该系统中，亲本LOS的相对分子质量为4715，而突变菌株的LOS表现出逐渐的糖类缺失，相对分子质量分别为4230、4089、3627、3262和3197。这些突变体在十二烷基硫酸钠-聚丙烯酰胺凝胶上的蛋白质图谱在质量上与亲本菌株相似。对五种针对奈瑟菌LOS的单克隆抗体的研究结果表明，突变LOS上存在共同以及独特的表位。对突变LOS的3-脱氧-D-甘露糖辛酮酸分析结果表明，大多数3-脱氧-D-甘露糖辛酮酸残基可能在C-4或C-5位被取代。对此类LOS突变体的化学和免疫学分析应能加速淋球菌LOS结构模型的发展。
