Isolation of f(c)5μ and fabμ fragments of human igm

Academic Article


  • It has been shown previously that preparation of F(c)5μ and Fabμ fragments from IgM is limited both by low yields and incomplete cleavage and that digestion with hot trypsin is superior to papain in the absence of cysteine. The present study demonstrates that by using trypsin digestion, F(c)5μ fragment is relatively much more stable than Fabμ fragment. Optimum conditions for splitting with trypsin were 60°C for 20 min. Sedimentation constants of F(c)5μ and Fabμ fragments were 10.9 and 3.7 S, respectively. Molecular weights derived from polyacrylamide disc electrophoresis in sodium dodecyl sulfate were 340 000 and 48 000 for F(c)5μ and Fabμ respectively. The molecular weight of F(c)5μ fragment falls to 33 600 after partial oxidative sulfitolysis. Amino acid and sugar composition of the fragments were determined and accounted for approximately 85 % of the IgM molecule. That portion which was lost is most likely a glycopeptide cleaved from the hinge area. Copyright © 1973 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
  • Authors

    Published In

    Digital Object Identifier (doi)

    Author List

  • Zián J; Bennett JC
  • Start Page

  • 415
  • End Page

  • 419
  • Volume

  • 3
  • Issue

  • 7