Single-stranded endonuclease activity in the excretory--secretory products of Trichinella spiralis and Trichinella pseudospiralis

Parasitology. 2000 May:120 ( Pt 5):527-33. doi: 10.1017/s0031182099005879.

Abstract

A novel acidic extracellular single-stranded endonuclease was demonstrated for the first time in the excretory-secretory (E-S) products of 2 species of Trichinella. Unlike the double-stranded endonuclease reported earlier, the single-stranded molecule is divalent cation independent and is detected in both T. spiralis and T. pseudospiralis E-S products. It hydrolysed single-stranded DNA and RNA at comparable rates. The single-stranded endonuclease was sensitive to inhibition by Zn2+ and to high concentrations of NaCl. Zymographic analysis indicated that it was encoded by at least 3 peptides of Mr approximately 50-60 kDa. The rate of hydrolysis of single-stranded targets by the E-S products was substantially higher than that of the double-stranded molecule. Due to the differences in peptide profile, divalent cation dependence, and species-specific expression, the single and double-stranded endonucleases are likely to be encoded by different proteins and may have different functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cations, Divalent / metabolism
  • Endonucleases / antagonists & inhibitors
  • Endonucleases / metabolism*
  • Helminth Proteins / metabolism*
  • Mice
  • Mice, Inbred ICR
  • Species Specificity
  • Trichinella / enzymology*
  • Trichinella spiralis / enzymology*
  • Trichinellosis / parasitology*

Substances

  • Cations, Divalent
  • Helminth Proteins
  • Endonucleases