Vinogradov Evgeny, St Michael Frank, Homma Kiyonobu, Sharma Ashu, Cox Andrew D
Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON, K1A 0R6, Canada.
Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON, K1A 0R6, Canada.
Carbohydr Res. 2017 Feb 22;440-441:38-42. doi: 10.1016/j.carres.2017.01.009. Epub 2017 Jan 28.
Fusobacterium nucleatum is an anaerobic bacterium found in the human mouth where it causes periodontitis. Recently, it has been gaining attention as a potential causative agent for colorectal cancer and is strongly linked with pregnancy complications including pre-term and still births. Little is known about virulence factors of this organism and thus we have initiated studies to examine the bacterial surface glycochemistry. Consistent with a recent paper suggesting that F. nucleatum strain 10593 can synthesize sialic acid, a staining technique identified sialic acid on the bacterial surface. We isolated lipopolysaccharide from this F. nucleatum strain and performed structural analysis on the O-antigen. Our studies identified a trisaccharide repeating unit of the O-antigen with the following structure: -[→4)-α-Neup5Ac-(2 → 4)-β-d-Galp-(1 → 3)-α-d-FucpNAc4NAc-(1-]- where Ac indicates 4-N-acetylation of ∼30% FucNAc4N residues. The presence of sialic acid as a constituent of the O-antigen is consistent with recent data identifying de novo sialic acid synthesis in this strain.
具核梭杆菌是一种存在于人类口腔中的厌氧菌，可引发牙周炎。最近，它作为结直肠癌的潜在致病因素受到关注，并且与包括早产和死产在内的妊娠并发症密切相关。人们对这种微生物的毒力因子知之甚少，因此我们启动了研究来检测细菌表面糖化学。与最近一篇表明具核梭杆菌10593菌株能够合成唾液酸的论文一致，一种染色技术在细菌表面鉴定出了唾液酸。我们从该具核梭杆菌菌株中分离出脂多糖，并对O抗原进行了结构分析。我们的研究确定了O抗原的一个三糖重复单元，其结构如下：-[→4)-α-Neup5Ac-(2→4)-β-d-Galp-(1→3)-α-d-FucpNAc4NAc-(1-]，其中Ac表示约30%的FucNAc4N残基的4-N-乙酰化。唾液酸作为O抗原的组成成分的存在与最近鉴定出该菌株从头合成唾液酸的数据一致。
