Laboratoire BMM, centre Ifremer de Brest, ZI pointe du diable, 29280 Plouzané, France.
Service commun de résonnance magnétique nucléaire, Faculté de science de Brest, Université de Bretagne Occidentale, 6 av. Victor Le Gorgeu, 29238 Brest Cedex 3, France.
Carbohydr Polym. 2015 Jun 25;124:347-56. doi: 10.1016/j.carbpol.2015.02.038. Epub 2015 Feb 26.
We have studied the exopolysaccharide produced by Cobetia marina DSMZ 4741, a marine bacterium isolated from coastal seawater. This strain is able to produce a polysaccharide in presence of carbon sources as glucose, mannitol and alginate. The maximum production occurs in aerobic condition, during the end of the exponential phase. The polymer is a non-viscous, acidic heteropolysaccharide of 270kDa constituted of a repeating unit of: This kind of chemical structure is generally related to K-antigen polysaccharide of pathogenic Escherichia coli strains. This is the first time this type of EPS is described from a marine bacterium. Moreover the polysaccharide exhibits a pyruvate substitution on its 3-deoxy-d-manno-oct-2-ulosonic acid (KDO) residue never encountered before. The discovery of such an unexpected EPS with high biotechnological potential is a new incentive for a better exploration of bioactive marine resources.
我们研究了 Marine bacterium（海洋细菌）从沿海海水中分离出的一株 Cobetia marina DSMZ 4741 产生的胞外多糖。该菌株能够在碳源（如葡萄糖、甘露醇和藻酸盐）存在的情况下产生多糖。最大产量发生在有氧条件下，在指数期结束时。聚合物是一种非粘性、酸性杂多糖，分子量为 270kDa，由重复单元组成：这种化学结构通常与致病性大肠杆菌菌株的 K 抗原多糖有关。这是首次从海洋细菌中描述这种类型的 EPS。此外，多糖在其 3-脱氧-d-甘露-oct-2-ulosonic 酸（KDO）残基上表现出丙酮酸取代，这是以前从未遇到过的。这种具有高生物技术潜力的意想不到的 EPS 的发现，为更好地探索生物活性海洋资源提供了新的动力。
