N-acetyl-β-d-hexosaminidase from Trichomonas vaginalis: substrate specificity and activity of inhibitors

Autor: Cecile Tournaire‐Arellano, R Caujolle, A. Sanon, S. Younes El Hage, Christian Bories, Philippe M. Loiseau
Rok vydání: 2005
Předmět:
Zdroj: Biomedicine & Pharmacotherapy. 59:245-248
ISSN: 0753-3322
Popis: Among chitinolytic activities previously described in Trichomonas vaginalis, N-acetyl-beta-D-hexosaminidase (NAHase) was the enzyme system expressing the highest level of specific activity. We report here some biochemical characteristics of NAHase purified from T. vaginalis. We found at first that the use of 4-methylumbellifferyl-substrate was responsible for a substrate affinity for the enzyme, about 1000-fold higher than those when using p-nitrophenyl-substrates (PNP). Whereas the optimum pH was 7.0 using PNP-substrate, it was at 4.5 using 4-methylumbelliferyl-substrate. Four different substrates were compared for their action on T. vaginalis NAHase and we have found that N-acetyl-beta-D-glucosaminide substrate was the most specific. DTT had no effect on enzyme activity suggesting that thiol group are not involved at the catalytic site. The use of previously described inhibitors showed a positive correlation between trichomonacidal activity and NAHase inhibition.
Databáze: OpenAIRE