Affordable Access

Publisher Website

Post-translational modification of the pyruvate phosphate dikinase from Trypanosoma cruzi

Parasitology International
DOI: 10.1016/j.parint.2013.09.007
  • Trypanosoma Cruzi
  • Glycosome
  • Phosphorylation
  • Pyruvate Phosphate Dikinase
  • Biology


Abstract In kinetoplastids such as Trypanosoma cruzi, glycolysis is compartmentalized in peroxisome-like organelles called glycosomes. Pyruvate phosphate dikinase (PPDK), an auxiliary enzyme of glycolysis, is also located in the glycosomes. We have detected that this protein is post-translationally modified by phosphorylation and proteolytic cleavage. On western blots of T. cruzi epimastigotes, two PPDK forms were found with apparent MW of 100kDa and 75kDa, the latter one being phosphorylated at Thr481, a residue present in a highly conserved region. In subcellular localization assays the 75kDa PPDK was located peripherally at the glycosomal membrane. Both PPDK forms were found in all life-cycle stages of the parasite. When probing for both PPDK forms during a growth of epimastigotes in batch culture, an increase in the level of the 75kDa form and a decrease of the 100kDa one were observed by western blot analysis, signifying that glucose starvation and the concomitant switch of the metabolism to amino acid catabolism may play a role in the post-translational processing of the PPDK. Either one or both of the processes, phosphorylation and proteolytic cleavage of PPDK, result in inactivation of the enzyme. It remains to be established whether the phenomenon exerts a regulatory function.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Cloning of a pyruvate phosphate dikinase from Tryp...

on Molecular and Biochemical Para... February 2001

Cloning of a pyruvate phosphate dikinase fromTrypa...

on Molecular and Biochemical Para... Jan 01, 2001

On the post-translational modifications at the C-t...

on FEMS Microbiology Letters Dec 15, 1992

Pyruvate phosphate dikinase and pyrophosphate meta...

on Comparative biochemistry and p... August 2004
More articles like this..