Isolation of an Electrogenic K+/Ca2+ Ionophore from an Ionophoroprotein of Beef Heart Mitochondria
Abstract
A K+/Ca2+ electrogenic ionophore has been isolated from an ionophoroprotein of beef heart mitochondria and identified as a neutral peptide of molecular weight 1600. The amino acid composition and cationic specificity of the ionophore have been determined. The free ionophore was released from the ionophoroprotein as a consequence of tryptic digestion. The ionophoroprotein can be converted to an ionophoro peptide (molecular weight 5,100) by proteolysis without release of the free ionophore. The isolation of a K+/Ca2+ ionophore thus provides an introduction to the general technology of extracting ionophoro proteins and ofreleasing ionophores from these proteins by proteolytic digestion.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- September 1977
- DOI:
- 10.1073/pnas.74.9.3667
- Bibcode:
- 1977PNAS...74.3667B