Fialho Arsenio M, Moreira Leonilde M, Granja Ana Teresa, Popescu Alma O, Hoffmann Karen, Sá-Correia Isabel
IBB-Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
Appl Microbiol Biotechnol. 2008 Jul;79(6):889-900. doi: 10.1007/s00253-008-1496-0. Epub 2008 May 28.
Bacterial exopolysaccharides (EPS) are products of biotechnology that are of high interest due to their rheological properties. This is the case of sphingans, a group of structurally related EPS secreted by members of the genus Sphingomonas. Among these, gellan is a multifunctional gelling agent produced in high yields by the non-pathogenic strain Sphingomonas elodea ATCC 31461. In its native form, gellan is a linear anionic EPS based on a tetrasaccharide repeat unit composed of two molecules of D: -glucose, one of L: -rhamnose and one of D: -glucuronic acid. The native gellan is partially esterified with acyl substituents (1 mol of glycerate and 0.5 mol of acetate) per repeat unit. Gellan has unique characteristics and has many applications, particularly in the food, pharmaceutical, and biomedical fields. This review summarizes current knowledge on the structure and properties of gellan and provides details about the biosynthesis of this exopolysaccharide. In addition, a highlight of the importance of gellan in industrial and medicinal applications is given.
细菌胞外多糖（EPS）是一类具有重要生物技术价值的产物，因其流变学特性而备受关注。鞘脂聚糖就是这样的例子，它是由鞘氨醇单胞菌属成员分泌的一组结构相关的EPS。其中，结冷胶是由非致病性菌株伊乐藻鞘氨醇单胞菌ATCC 31461高产生产的多功能胶凝剂。天然形式的结冷胶是一种基于四糖重复单元的线性阴离子EPS，该重复单元由两分子D-葡萄糖、一分子L-鼠李糖和一分子D-葡萄糖醛酸组成。天然结冷胶每个重复单元被酰基取代基（1摩尔甘油酸酯和0.5摩尔乙酸酯）部分酯化。结冷胶具有独特的特性并具有许多应用，特别是在食品、制药和生物医学领域。本综述总结了目前关于结冷胶结构和性质的知识，并详细介绍了这种胞外多糖的生物合成。此外，还强调了结冷胶在工业和医学应用中的重要性。
