Biochemical characterization of trypanosoma brucei tricorn interacting factor-3 in determining pathogenicity of the parasite against African trypanosomiasis

  • E. Mueni Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology
  • F. Ng’ong’a Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology
  • S. Nyanjom Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology

Abstract

Trypanosoma brucei brucei peptidases including tricorn interacting factor-3 (F3), a zinc metallo- aminopeptidases of the M1 family are virulent factors involved in cleaving neutral amino acids from the N-terminus of oligopeptides ensuring a pool of free amino acids for other metabolic functions. To explore the possibility of tricorn interacting factor-3 as being potential drug target for inhibition and development of novel therapeutic agents the specificity of  substrate  was  explored  using  different  flourogenic AMC substrates (H-Ala-AMC, H-Met-AMC, H-Gly-AMC). The objective of this study was to determine substrate specificity. The reactions were carried out in a 96 microtitre plate and release of fluorophore was measured at 528nm upon excitation at 410nm using Synergy™ HT Multi-Mode Microplate Reader fluorescence. The enzyme showed distinct substrate preference to Met with a Kcat/km value of 1914.8059 compared to Gly and Ala with a Kcat/km value of 181.6162, 125.9097 respectively. Relative enzyme activity of 83.33 was observed at an optimum pH of 8.0 though its activity was retained over a wide range of pH of 3-10. The enzyme further proved sensitive towards bestatin, E-64,1,10 phenathroline with inhibition constant at 39.0625,51.2820 and 24.731 and insensitive towards leupeptin and pepstatin  (0.14749,0.02123) protease inhibitors respectively. In conclusion, tricorn interacting factor-3 shared general characteristics with the M1 family of aminopeptidases and this provides a basis for its function and study as drug target.

Published
2022-05-26
How to Cite
Mueni, E., Ng’ong’a, F., & Nyanjom, S. (2022). Biochemical characterization of trypanosoma brucei tricorn interacting factor-3 in determining pathogenicity of the parasite against African trypanosomiasis. East African Agricultural and Forestry Journal, 85(1-4), 9. Retrieved from https://www.kalro.org/www.eaafj.or.ke/index.php/path/article/view/504