Zhang Tianyu, Wang Lingyan, Xu Guiyun, Chen Yang, Zhang Yang, Li Yuan
Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, Peking Union Medical College, 100050 Beijing, China.
Curr Microbiol. 2006 Jan;52(1):55-9. doi: 10.1007/s00284-005-0096-9. Epub 2006 Jan 2.
Streptomyces sp.139 produces an exopolysaccharide (EPS) designated Ebosin with remarkable anti-rheumatic arthritis activity in vivo. The ste (Streptomyces eps) gene cluster required for Ebosin biosynthesis has been identified. According to similarities with other proteins in the database, ste22 shows high homology with glycosyltransferases originated from different microorganisms. In this study, the ste22 gene was disrupted by double crossover via homologous recombination. The EPS produced by the mutant strain Streptomyces sp.139 (ste22(-)) has a different monosaccharide composition profile in comparison with that of Ebosin. This derivative of Ebosin retained the original antagonistic activity of IL-1R in vitro but lost the bioactivities of anti-inflammation and pain relief in vivo.
链霉菌属菌株139产生一种胞外多糖（EPS），命名为埃博辛，在体内具有显著的抗风湿性关节炎活性。已鉴定出埃博辛生物合成所需的ste（链霉菌胞外多糖）基因簇。根据与数据库中其他蛋白质的相似性，ste22与源自不同微生物的糖基转移酶具有高度同源性。在本研究中，通过同源重组双交换破坏了ste22基因。突变菌株链霉菌属菌株139（ste22(-)）产生的EPS与埃博辛相比具有不同的单糖组成谱。埃博辛的这种衍生物在体外保留了原有的IL-1R拮抗活性，但在体内失去了抗炎和止痛生物活性。
