• Citer

Bacteriophage Mu repressor as a target for the Escherichia coli ATP-dependent Clp protease

par Laachouch, Jamal E;Desmet, Lucie;Geuskens, Vincent;Grimaud, Régis;Toussaint, Ariane
Référence EMBO journal, 15, 2, page (437-444)
Publication Publié, 1996-01

Article révisé par les pairs

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

Bacteriophage Mu repressor, which is stable in its wildtype form, can mutate to become sensitive to its Escherichia coli host ATP-dependent ClpXP protease. We further investigated the determinants of the mutant repressor's sensitivity to Clp. We show the crucial importance of a C-terminal, seven amino acid long sequence in which a single change is sufficient to decrease the rate of degradation of the protein. The sequence was fused at the C-terminal end of the CcdB and CcdA proteins encoded by plasmid F. CcdB, which is naturally stable, was unaffected, while CcdA, which is normally degraded by the Lon protease, became a substrate for ClpXP while remaining a substrate for Lon. In agreement with the current hypothesis on the mechanism of recognition of their substrates by energy- dependent proteases, these results support the existence, on the substrate polypeptides, of separate motifs responsible for recognition and cleavage by the protease.