SWP25, a novel protein associated with the Nosema bombycis endospore

J Eukaryot Microbiol. Mar-Apr 2009;56(2):113-8. doi: 10.1111/j.1550-7408.2008.00375.x.


Microsporidia are eukaryotic, obligate intracellular, spore-forming parasites. The resistant spores, which harbor a rigid cell wall, are critical for their host-to-host transmission and persistence in the environment. The spore wall comprises two major layers: the exospore and the endospore. In Nosema bombycis, two spore wall proteins have been characterized--an endosporal protein, SWP30, and an exosporal protein, SWP32. Here, we report the identification of the third spore wall protein of N. bombycis, SWP25, the gene of which has no known homologue. SWP25 is predicted to posses a signal peptide and a heparin-binding motif. Immunoelectron microscopy analysis showed that this protein is localized to the endospore. This characterization of a new spore wall protein of N. bombycis may facilitate our investigation of the relationship between N. bombycis and its host, Bombyx mori.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Fungal
  • Bombyx / microbiology
  • Cell Wall / chemistry
  • Fluorescent Antibody Technique
  • Fungal Proteins / chemistry
  • Fungal Proteins / isolation & purification*
  • Fungal Proteins / metabolism
  • Host-Pathogen Interactions
  • Membrane Proteins / isolation & purification*
  • Molecular Sequence Data
  • Nosema / chemistry*
  • Nosema / cytology*
  • Nosema / metabolism
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Spores, Fungal / chemistry


  • Antibodies, Fungal
  • Fungal Proteins
  • Membrane Proteins

Associated data

  • GENBANK/EF683102