title: Monosaccharide composition of the outer membrane lipopolysaccharide and O-chain from the freshwater cyanobacterium Microcystis aeruginosa NIES-87.
abstract: OBJECTIVE
  Bacterial lipopolysaccharide (LPS) protruding from the outermost layer of the outer membrane is expected to play an important role in cell physiology by interacting with molecules in the extracellular milieu; however, the structural and functional characteristics of these components in cyanobacteria remain largely unknown. We isolated water-soluble fractions of LPS and O-chain from the bloom-forming freshwater cyanobacterium Microcystis aeruginosa NIES-87 and identified their monosaccharide compositions.
  
  
  RESULTS
  SDS-PAGE followed by silver staining demonstrated that the isolated total LPS was the smooth type with different numbers of repeating sugar units in the O-chain region. GC/MS analysis after acid hydrolysis, reduction and acetylation treatments indicated that the neutral monosaccharide components of the total LPS include glucose, rhamnose, mannose, galactose and xylose (in decreasing order of weight percentage), while only glucose was detected in the purified O-chain fraction. MALDI-TOF MS analysis suggested that the O-chain fraction is composed of repeating glucose and methylated glucose disaccharide units.
  
  
  CONCLUSIONS
  Our results indicate that the monosaccharide composition of M. aeruginosa O-chain is relatively simple.
  
  
  CONCLUSIONS
  Although further studies are necessary, these findings provide fundamental information for understanding the structural and functional properties of cyanobacterial LPS and O-chain.
authors: Department of Civil Engineering, Tokyo Institute of Technology, Tokyo, Japan. fujii.m.ah@m.titech.ac.jp
authors: M
authors: M
authors: Fujii
authors: Y
authors: Y
authors: Sato
authors: H
authors: H
authors: Ito
authors: Y
authors: Y
authors: Masago
authors: T
authors: T
authors: Omura
mesh_terms: D002462:Cell Membrane / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D008401:Gas Chromatography-Mass Spectrometry; D005947:Glucose / Q000737:chemistry; D008070:Lipopolysaccharides / Q000737:chemistry*; D046931:Microcystis / Q000737:chemistry*; D009005:Monosaccharides / Q000737:chemistry*; D016622:Silver Staining; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D008070:Lipopolysaccharides; D009005:Monosaccharides; D005947:Glucose