Beschreibung:
Several EF‐hand recoverin mutants were obtained and their abilities to bind to photoreceptor membranes and to inhibit rhodopsin kinase were determined. The mutants with the ‘spoiled' 2nd, 3rd or (2nd+3rd) EF‐hand structures did not act upon the kinase activity in the μM range of Ca2+ concentrations. Mutations of the 4th EF hand, which ‘repaired' its Ca2+‐binding activity, resulted in recoverin with three ‘working' Ca2+‐binding sites. The latter mutant inhibited rhodopsin kinase even more effectively than the wild‐type recoverin, containing two working Ca2+‐binding structures.