Parasites - Molecular Parasitology - Nucleoside Transport - Purine and Pyrimidine Metabolism - Polyamine Biosynthesis 

Amalgamating tools from the diverse scientific disciplines of molecular biology, biochemistry, genetics, cell biology, immunocytochemistry, structural biology, and computational chemistry, the Ullman laboratory focuses on unique pathways in protozoan parasites that might be amenable to therapeutic manipulation. We have four areas of interest: (1) the purine salvage pathway; (2) the polyamine biosynthetic pathway; (3) nucleoside transporters; and (4) organellar biogenesis and protein import.

The parasite genera on which our laboratory focuses include Leishmania, Trypanosoma, Toxoplasma, and Plasmodium, the causative agents of leishmaniasis, African sleeping sickness, toxoplasmosis, and malaria, respectively. We have cloned, sequenced, and characterized the genes encoding the key proteins in all of these pathways. The genes serve as the molecular cornerstone for genetic and biochemical experiments to: (1) evaluate gene function in intact parasites using targeted gene replacmement strategies; and (2) to determine biochemical characteristics and 3-dimensional structure after gene overexpression in a variety of heterologous expression systems.

Recent Publications:

1. Roberts S.C., Scott J., Gasteier J.E., Jiang Y., Brooks B., Jardim A., Carter N.S., Heby O., Ullman B. S-Adenosylmethionine decarboxylase from Leishmania donovani: Molecular, genetic, and biochemical characterization of null mutants and overproducers J. Biol. Chem. [epub ahead of print] (2002).

2. Rager, N., Ben Mamoun, C., Carter, N.S., Goldberg, D.E., and Ullman, B. Localization of the Plasmodium falciparum PfNT1 Nucleoside Transporter to the Parasite Plasma Membrane. J. Biol. Chem. 276: 41095-9 (2001).

3. Dubessay, P., Ravel, C., Bastien, P., Lignon, M.F., Ullman, B., Pages, M., and Blaineau, C. Effect of Large Targeted Deletions on the Mitotic Stability of an Extrachromosome Mediating Drug-Resistance in Leishmania. Nucl. Acids Res. 29:3231-3240 (2001).

4. Roberts, S., Jiang, Y., Jardim, A., Carter, N.S., Heby, O., and Ullman, B. Spermidine Synthase from Leishmania donovani: Gene Cloning and Characterization of Null Mutants Mol. Biochem. Parasitol. 115: 217-26 (2001).

5. Carter, N.S., Landfear, S.M., and Ullman, B. Nucleoside Transporters of Parasitic Protozoa. Trends Parasitol. 17: 142-4 (2001).