Leishmaniasis is a wide spread tropical disease caused by protozoan parasite Leishmania which belongs
to order kinetoplastida and family trypanosomatidae. Ornithine decarboxylase is key enzyme in polyamine
biosynthesis in Leishmania donovani. Here, we report biochemical characterization of ornithine decarboxylase
from L. donovani. Furthermore, we have also investigated the role of N-terminal extension (250
amino acids) found in ornithine decarboxylase of L. donovani (LdODC). The removal of N-terminal extended
region of LdODC results in improved stability of the protein. However, the truncated LdODC does not show any activity.
Apparently, while N-terminal extended region of LdODC helps in proper folding of the protein for catalytic activity, there
is a stability trade-off. The native full length LdODC with N-terminal extension has activity but lower stability. Thus,
there is trade off of conformational stability for enzyme activity. Comparison of biochemical properties of both, fulllength
and truncated enzymes, have provided interesting insights about the role of N-terminal extension in the protein.
Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, -781039, India.