Abstract
Encephalitozoon cuniculi and E. hellem are often recognized as the agents of human microsporidiosis, but less than optimal therapy is available for treatment. The identification of enzymes critical to the parasitic life cycle is an important step in finding targets for potential drug development. Aminopeptidase gene sequences were obtained from cDNA and gDNA from avian and human E. hellem isolates and from a rabbit E. cuniculi isolate. At the amino acid level, the aminopeptidase sequences from the E. hellem human and bird isolates share >99% identity and are nearly 70% identical with the E. cuniculi sequence. Conserved HEXXH and GAMEN motifs classify the predicted aminopeptidase in the MA clan of the M1 family. The obtained aminopeptidase gene sequences are likely homologous to the previously reported E. cuniculi glutamyl aminopeptidase. The conservation of this aminopeptidase between species and divergence from mammalian aminopeptidases indicate that this enzyme may be a valid target for drug therapy.
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Acknowledgements
The authors thank Kathleen Logan and Douglas Melendy for excellent technical assistance. This investigation was supported by the Schubot Exotic Bird Health Center, Texas A&M University, and Texas Agricultural Experiment Station Project H6261. All experiments were conducted in compliance with the laws of the countries in which they were performed.
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Waters, P.F., Snowden, K.F. & Holman, P.J. A comparison of homologous genes encoding aminopeptidases among bird and human Encephalitozoon hellem isolates and a rabbit E. cuniculi isolate. Parasitol Res 93, 410–418 (2004). https://doi.org/10.1007/s00436-004-1148-y
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DOI: https://doi.org/10.1007/s00436-004-1148-y