Primary structure of the N-linked carbohydrate chains of Calreticulin from spinach leaves

Glycoconj J. 1996 Dec;13(6):977-83. doi: 10.1007/BF01053193.


Calreticulin is a multifunctional Ca(2+)-binding protein of the endoplasmic reticulum of most eukaryotic cells. The 56 kDa Calreticulin glycoprotein isolated from spinach (Spinacia oleracea L.) leaves was N-deglycosylated by PNGase-F digestion. The carbohydrate moiety was isolated by gel permeation chromatography and purified by high-pH anion-exchange chromatography. The fractions were investigated by 500 MHz 1H-NMR spectroscopy, in combination with monosaccharide analysis and fast-atom bombardment-mass spectrometry. The following carbohydrate structure could be established as the major component (Man8GlcNAc2): (sequence see text) Heterogeneity was demonstrated by the presence of two minor components being Man7GlcNAc2 lacking a terminal residue (D1 or D3), compared to the major component. A cross-reactivity with an antibody against the endoplasmic reticulum retention signal HDEL was also found.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium-Binding Proteins / chemistry*
  • Calcium-Binding Proteins / immunology
  • Calreticulin
  • Carbohydrate Sequence
  • Carbohydrates / analysis
  • Chromatography, Gel
  • Electrophoresis, Polyacrylamide Gel
  • Magnetic Resonance Spectroscopy
  • Molecular Sequence Data
  • Molecular Structure
  • Plant Leaves / chemistry
  • Plant Proteins / analysis
  • Plant Proteins / chemistry
  • Ribonucleoproteins / chemistry*
  • Ribonucleoproteins / immunology
  • Spinacia oleracea / chemistry*


  • Calcium-Binding Proteins
  • Calreticulin
  • Carbohydrates
  • Plant Proteins
  • Ribonucleoproteins