Gunawardena S, Reddy G P, Wang Y, Kolli V S, Orlando R, Morris J G, Bush C A
Department of Chemistry and Biochemistry, University of Maryland Baltimore County 21250, USA.
Carbohydr Res. 1998 Jun;309(1):65-76. doi: 10.1016/s0008-6215(98)00115-3.
Vibrio vulnificus strains isolated from septicemia cases and from the environment show a wide variety of capsular types. In an attempt to find common structural features which can be correlated with pathogenicity and toxicity, we have determined structures of the capsular polysaccharides (CPS) from several pathogenic strains. We report the complete structure of the polysaccharide from the pathogenic V. vulnificus strain ATCC 27562 using a combination of homonuclear and heteronuclear one-dimensional and two dimensional NMR experiments. The 13C and 1H NMR spectra, including the exchangeable amide proton resonances, have been completely assigned. The amide linkage between Ser and C6 of GalA has been unambiguously determined by water-suppressed 2D NOESY. To verify the structure established by NMR, we have fragmented the polymer employing the Smith degradation procedure. The Smith product identified by NMR and matrix-assisted laser desorption mass spectrometry is consistent with the proposed structure for the CPS, which is composed of D-GlcNAc, MurNAc, D-GalA, L-Rha and is serine-linked as shown: [formula: see text]
从败血症病例和环境中分离出的创伤弧菌菌株表现出多种荚膜类型。为了寻找与致病性和毒性相关的共同结构特征，我们确定了几种致病菌株的荚膜多糖（CPS）结构。我们结合同核和异核一维及二维核磁共振实验，报告了致病创伤弧菌菌株ATCC 27562多糖的完整结构。13C和1H核磁共振谱，包括可交换酰胺质子共振，已被完全归属。通过水抑制二维NOESY明确确定了Ser与GalA的C6之间的酰胺键。为了验证核磁共振确定的结构，我们采用史密斯降解法对聚合物进行了片段化。通过核磁共振和基质辅助激光解吸质谱鉴定的史密斯产物与所提出的CPS结构一致，该结构由D-GlcNAc、MurNAc、D-GalA、L-Rha组成，并如所示通过丝氨酸连接：[化学式：见原文]
