Molecular cloning, biochemical and structural analysis of elongation factor-1 alpha from Leishmania donovani: comparison with the mammalian homologue.
The Src-homology 2 domain containing protein tyrosine phosphatase-1 (SHP-1) is involved in the pathogenesis of infection with Leishmania. Recently, we identified elongation factor-1 alpha (EF-1 alpha) from Leishmania donovani as a SHP-1 binding and activating protein [J. Biol. Chem. 277 (2002) 50190]. To characterize this apparent Leishmania virulence factor further, the cDNA encoding L. donovani EF-1 alpha was cloned and sequenced. Whereas nearly complete sequence conservation was observed amongst EF-1 alpha proteins from trypanosomatids, the deduced amino acid sequence of EF-1 alpha of L. donovani when compared to mammalian EF-1 alpha sequences showed a number of significant changes. Protein structure modeling-based upon the known crystal structure of EF-1 alpha for Saccharomyces cerevisiae-identified a hairpin loop present in mammalian EF-1 alpha and absent from the Leishmania protein which corresponded to a 12 amino acid deletion. Consistent with these structural differences, the sub-cellular distributions of L. donovani EF-1 alpha and host EF-1 alpha were strikingly different. Interestingly, infection of macrophages with L. donovani caused redistribution of host as well as pathogen EF-1 alpha. Since EF-1 alpha is essential for survival, the distinct biochemical and structural properties of Leishmania EF-1 alpha may provide a novel target for drug development.
Nandan
Devki
D
Department of Medicine, Division of Infectious Diseases, Faculty of Medicine, The Research Institute of the Vancouver Hospital and Health Sciences Center, The University of British Columbia, Vancouver, BC, Canada V5Z 3J5. dnandan@interchange.ubc.ca
Cherkasov
Artem
A
Sabouti
Rafat
R
Yi
Taolin
T
Reiner
Neil E
NE
D000595:Amino Acid Sequence; D000818:Animals; D002458:Cell Fractionation; D003001:Cloning, Molecular; D004789:Enzyme Activation; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007893:Leishmania donovani / Q000378:metabolism*; D007898:Leishmaniasis, Visceral / Q000097:blood / Q000276:immunology; D008264:Macrophages / Q000166:cytology / Q000378:metabolism / Q000469:parasitology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020648:Peptide Elongation Factor 1 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D054645:Protein Phosphatase 1; D017434:Protein Structure, Tertiary; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment
D047908:Intracellular Signaling Peptides and Proteins; D020648:Peptide Elongation Factor 1; D015800:Protozoan Proteins; D054645:Protein Phosphatase 1; C509249:PTPN6 protein, human; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases