Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

A novel flagellar Ca2+-binding protein in trypanosomes. J Biol Chem 1989 Nov 05;264(31):18627-31



Pubmed ID



A 24-kDa protein of Trypanosoma cruzi, the protozoan parasite that causes Chagas' disease, is recognized by antisera from both humans and experimental animals infected with this organism. Near its C terminus are two regions that have sequence similarity with several Ca2+-binding proteins and that conform to the "E-F hand" Ca2+-binding structure. We expressed a cDNA encoding this protein in Escherichia coli and showed that both the recombinant protein and the 24-kDa native trypanosome protein do indeed bind Ca2+. The protein's low Ca2+-binding capacity (less than 2 mol of Ca2+/mol of protein) and high Ca2+-binding affinity (apparent Kd less than 50 microM Ca2+) are consistent with binding of Ca2+ via the E-F hand structures. Immunofluorescence assays using a mouse antiserum directed against the fusion protein localized the native protein to the trypanosome's flagellum. The protein's abundance, Ca2+-binding property, and flagellar localization suggest that it participates in molecular processes associated with the high motility of the parasite.

Author List

Engman DM, Krause KH, Blumin JH, Kim KS, Kirchhoff LV, Donelson JE


Joel H. Blumin MD Chief, Professor in the Otolaryngology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Amino Acid Sequence
Blotting, Western
Calcium-Binding Proteins
Escherichia coli
Fluorescent Antibody Technique
Molecular Sequence Data
Protein Conformation
Protozoan Proteins
Recombinant Proteins
Trypanosoma cruzi
jenkins-FCD Prod-400 0f9a74600e4e79798f8fa6f545ea115f3dd948b2