PREPARATION OF MYRISTOYLATED AND NONMYRIS TOYLATED RECOMBINANT RECOVERINS IN ESCHERICHIA-COLI AND COMPARISON OF THEIR FUNCTIONAL ACTIVITIES

A recombinant plasmid was constructed for expressing a gene for bovine recoverin under the control of the lac promoter. Coexpression of the recoverin and N-myristoyl transferase genes was performed to prepare r ecombinant myristoylated recoverin. The obtained systems provide high levels of biosynthesis of the recombinant recoverins in the E. coli ce lls. Using a reconstructed system, containing urea washed rod outer se gment membranes, purified rhodopsin kinase (RK), and a recoverin, it w as shown that the three recoverin forms (natural, recombinant nonmyris toylated, and recombinant myristoylated ones) perform the calcium-depe ndent regulation of the activity of RK with half a maximum effect at a free calcium concentration of 2 mu M. Interestingly, the N-terminal m yristoylation of recoverin increased substantially its functional acti vity.