PDF(Pubmed)
Abstract：
Lipopolysaccharides (LPSs) are major components of the outer membranes of Gram-negative bacteria. In this work, the structure of the O-polysaccharide of Ochrobactrum quorumnocens T1Kr02 was identified by nuclear magnetic resonance (NMR), and the physical-chemical properties and biological activity of LPS were also investigated. The NMR analysis showed that the O-polysaccharide has the following structure: →2)-β-d-Fucf-(1→3)-β-d-Fucp-(1→. The structure of the periplasmic glucan coextracted with LPS was established by NMR spectroscopy and chemical methods: →2)-β-d-Glcp-(1→. Non-stoichiometric modifications were identified in both polysaccharides: 50% of d-fucofuranose residues at position 3 were O-acetylated, and 15% of d-Glcp residues at position 6 were linked with succinate. This is the first report of a polysaccharide containing both d-fucopyranose and d-fucofuranose residues. The fatty acid analysis of the LPS showed the prevalence of 3-hydroxytetradecanoic, hexadecenoic, octadecenoic, lactobacillic, and 27-hydroxyoctacosanoic acids. The dynamic light scattering demonstrated that LPS (in an aqueous solution) formed supramolecular particles with a size of 72.2 nm and a zeta-potential of -21.5 mV. The LPS solution (10 mkg/mL) promoted the growth of potato microplants under in vitro conditions. Thus, LPS of O. quorumnocens T1Kr02 can be recommended as a promoter for plants and as a source of biotechnological production of d-fucose.
摘要：
脂多糖(LPSs)是革兰氏阴性菌外膜的主要成分。在这项工作中,通过核磁共振（NMR）鉴定了五色杆菌T1Kr02的O-多糖的结构，并对LPS的理化性质和生物活性进行了研究。NMR分析表明，O-多糖具有以下结构：→2）-β-d-Fucf-（1→3）-β-d-Fucp-（1→。通过NMR光谱和化学方法建立了与LPS共提取的周质葡聚糖的结构：→2）-β-d-Glcp-（1→。在两种多糖中均鉴定出非化学计量修饰：位置3处的50％的d-岩藻呋喃糖残基是O-乙酰化的，位置6处的15%的d-Glcp残基与琥珀酸连接。这是含有d-岩藻吡喃糖和d-岩藻呋喃糖残基的多糖的首次报道。LPS的脂肪酸分析显示3-羟基十四烷酸的患病率，十六碳烯,十八碳烯,乳杆菌,和27-羟基二十八烷酸。动态光散射表明，LPS（在水溶液中）形成了尺寸为72.2nm，ζ电位为-21.5mV的超分子颗粒。LPS溶液（10mkg/mL）在体外条件下促进了马铃薯微植物的生长。因此，可以推荐O.quorumnocensT1Kr02的LPS作为植物的启动子和d-岩藻糖的生物技术生产的来源。
