Purification of Human Complement Component C4 and Sample Preparation for Structural Biology Applications

Methods Mol Biol. 2021:2227:249-264. doi: 10.1007/978-1-0716-1016-9_22.

Abstract

Activated complement component C4 (C4b) is the nonenzymatic component of the classical pathway (CP) convertases of the complement system. Preparation of C4 and C4b samples suitable for structural biology studies is challenging due to low yields and complexity of recombinant C4 production protocols reported so far and heterogeneity of C4 in native sources. Here we present a purification protocol for human C4 and describe sample preparation methods for structural investigation of C4 and its complexes by crystallography, small angle X-ray scattering, and electron microscopy.

Keywords: Complement C4; Gel filtration; Ion exchange; Negative stain electron microscopy; Small angle X-ray scattering; X-ray crystallography.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biology / methods
  • Chromatography, Gel / methods
  • Complement C4 / chemistry*
  • Complement C4 / isolation & purification*
  • Crystallography, X-Ray / methods
  • Humans
  • Ion Exchange
  • Microscopy, Electron / methods
  • Negative Staining / methods
  • Protein Conformation
  • Proteomics / methods*
  • Scattering, Small Angle
  • X-Ray Diffraction / methods

Substances

  • Complement C4