title: A comparison of homologous genes encoding aminopeptidases among bird and human Encephalitozoon hellem isolates and a rabbit E. cuniculi isolate.
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.
authors.affiliation: Department of Veterinary Pathobiology, The Texas Veterinary Medical Center, Texas A&M University, College Station, TX 77843-4467, USA.
authors.forename: Paulette F
authors.initials: PF
authors.lastname: Waters
authors.forename: Karen F
authors.initials: KF
authors.lastname: Snowden
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Holman
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000737:chemistry / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D001717:Birds / Q000469:parasitology; D018076:DNA, Complementary / Q000737:chemistry; D016054:DNA, Protozoan / Q000737:chemistry; D016819:Encephalitozoon / Q000201:enzymology* / Q000235:genetics* / Q000302:isolation & purification; D009670:Encephalitozoon cuniculi / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D016890:Encephalitozoonosis / Q000469:parasitology / Q000662:veterinary; D006801:Humans; D008322:Mammals / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D011817:Rabbits / Q000469:parasitology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
chemical_list: D018076:DNA, Complementary; D016054:DNA, Protozoan; D000626:Aminopeptidases