The α-helical regions of KERP1 are important in Entamoeba histolytica adherence to human cells

Sci Rep. 2013:3:1171. doi: 10.1038/srep01171. Epub 2013 Jan 30.

Abstract

The lysine and glutamic acid rich protein KERP1 is a unique surface adhesion factor associated with virulence in the human pathogen Entamoeba histolytica. Both the function and structure of this protein remain unknown to this date. Here, we used circular dichroism, analytical ultracentrifugation and bioinformatics modeling to characterize the structure of KERP1. Our findings revealed that it is an α-helical rich protein organized as a trimer, endowed with a very high thermal stability (Tm = 89.6°C). Bioinformatics sequence analyses and 3D-structural modeling indicates that KERP1 central segments could account for protein trimerization. Relevantly, expressing the central region of KERP1 in living parasites, impair their capacity to adhere to human cells. Our observations suggest a link between the inhibitory effect of the isolated central region and the structural features of KERP1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Caco-2 Cells
  • Cell Adhesion
  • Cell Line
  • Circular Dichroism
  • Computational Biology
  • Entamoeba histolytica / metabolism*
  • Entamoeba histolytica / pathogenicity
  • Humans
  • Molecular Sequence Data
  • Protein Multimerization
  • Protein Structure, Secondary
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Temperature
  • Ultracentrifugation

Substances

  • KERP1 protein, Entamoeba histolytica
  • Protozoan Proteins
  • Recombinant Proteins