Ibarburu I, Soria-Díaz M E, Rodríguez-Carvajal M A, Velasco S E, Tejero-Mateo P, Gil-Serrano A M, Irastorza A, Dueñas M T
Departamento de Química Aplicada, Facultad de Ciencias Químicas, Universidad del País Vasco, San Sebastián, Spain.
J Appl Microbiol. 2007 Aug;103(2):477-86. doi: 10.1111/j.1365-2672.2006.03266.x.
To study the influence of medium constituents on growth, and exopolysaccharide (EPS) production by a strain of Oenococcus oeni. The structure of one of the EPSs has also been characterized.
EPS concentration was estimated by the phenol/sulfuric acid method. After purification and fractionation of crude EPSs, the sugar composition was determined by GLC-MS of the TMS methyl glycosides. The major polysaccharide is 2-substituted-(1-3)-beta-D-glucan. This structure was determined by methylation analysis and conventional (1)H- and (13)C-nuclear magnetic resonance spectroscopy. In addition, O. oeni synthesized two heteropolysaccharides, although a lesser proportion, constituted by galactose and glucose, and one of them also showed rhamnose. The sugar source has a clear influence on growth and EPS synthesis, and EPS production was not enhanced by adding ethanol or increasing the nitrogen source. EPS biosynthesis starts in the exponential growth phase, and continued during the stationary growth phase.
Higher EPS yields were obtained on cultures grown on glucose + fructose. O. oeni produces a beta-glucan, as the predominant EPS, and it is also able to produce two heteropolysaccharides.
This work provides a better understanding of EPS synthesis by O. oeni and shows the first EPS structure described for this species.
研究培养基成分对酒酒球菌菌株生长及胞外多糖（EPS）产生的影响。同时对其中一种EPS的结构进行了表征。
采用苯酚/硫酸法估算EPS浓度。对粗EPS进行纯化和分级分离后，通过TMS甲基糖苷的气相色谱-质谱联用（GLC-MS）测定糖组成。主要多糖为2-取代-(1-3)-β-D-葡聚糖。该结构通过甲基化分析以及常规的¹H-和¹³C-核磁共振光谱确定。此外，酒酒球菌还合成了两种杂多糖，尽管比例较小，由半乳糖和葡萄糖组成，其中一种还含有鼠李糖。糖源对生长和EPS合成有明显影响，添加乙醇或增加氮源并不能提高EPS产量。EPS生物合成始于指数生长期，并在稳定生长期持续进行。
在以葡萄糖+果糖为培养基的培养物中获得了更高的EPS产量。酒酒球菌产生一种β-葡聚糖作为主要的EPS，并且还能够产生两种杂多糖。
这项工作有助于更好地理解酒酒球菌的EPS合成，并展示了该物种描述的首个EPS结构。
