Xem trước tài liệu

Đang tải tài liệu...

Thông tin chi tiết tài liệu

Định dạng: PDF
Số trang: 7 trang
Dung lượng: 166 KB

Giới thiệu nội dung

Structures of Two O-Chain Polysaccharides of Citrobacter gillenii O9a,9b Lipopolysaccharide

Author(s): Tomasz Lipiński, George V. Zatonsky, Nina A. Kocharova, Michel Jaquinod, Eric Forest, Alexander S. Shashkov, Andrzej Gamian, Yuriy A. Knirel

Field: Biochemistry, Microbiology

Document Summary: This study investigates the lipopolysaccharide (LPS) from *Citrobacter gillenii* O9a,9b, focusing on its O-chain polysaccharides. Mild acid degradation of the LPS yielded a polysaccharide mixture that, upon fractionation, was revealed to consist of two distinct O-chain polysaccharides. One is a homopolymer of 4-amino-4,6-dideoxy-D-mannose (N-acetyl-D-perosamine), identified as PS2. The other, PS1, is a polysaccharide composed of repeating tetrasaccharide units also derived from N-acetyl-D-perosamine, with approximately 70% of the 3-substituted residue being O-acetylated. The structures were elucidated using methylation analysis, NMR spectroscopy (¹H, ¹³C, COSY, TOCSY, NOESY, HSQC, HMQC-TOCSY), and MALDI-TOF MS. The study also noted that only PS1 exhibited serological reactivity with homologous antiserum, suggesting that O-acetylation and chain length play roles in antigenicity.

Detailed Table of Contents:

  • Introduction
  • Materials and Methods
    • Bacterial strain, isolation and degradation of LPS
    • O-deacetylation
    • Sugar analysis
    • Methylation
    • NMR spectroscopy
    • Matrix-assisted laser desorption ionization (MALDI) MS
    • Rabbit antiserum, antigens and serological techniques
  • Results and Discussion
    • Polysaccharide structures
    • Serological studies
  • Acknowledgements
  • References