Binding protein-independent histidine permease mutants. Uncoupling of ATP hydrolysis from transmembrane signaling

• Published in: The Journal of biological chemistry 1991-09, Vol.266 (25), p.16293-16296
• Main Authors: PETRONILLI, V, FERRO-LUZZI AMES, G
• Format: Article
• Language: English
• Subjects: Adenosine Diphosphate - metabolism; Adenosine Triphosphate - metabolism; Amino Acid Transport Systems, Basic; Arginine - metabolism; ATP; ATP-Binding Cassette Transporters; Bacterial Proteins; Bacteriology; Biological and medical sciences; Biological Transport, Active; Cell Membrane - metabolism; Fundamental and applied biological sciences. Psychology; Hydrolysis; Kinetics; Membrane Proteins - genetics; Membrane Proteins - metabolism; Membrane Transport Proteins - genetics; Membrane Transport Proteins - metabolism; Microbiology; Mutation; Permeability, membrane transport, intracellular transport; Protein Conformation; Salmonella typhimurium - metabolism; Signal Transduction; Solubility
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)55294-7

Periplasmic permeases consist of a substrate-binding receptor, located in the periplasm, and a membrane-bound complex composed of two integral membrane proteins and two nucleotide-binding proteins. The receptor interacts with the membrane-bound complex, which, upon receiving this signal, is postulated to hydrolyze ATP and translocate the substrate. We show that a class of mutations in the membrane-bound complex of the histidine permease, which allow transport in the absence of the substrate-binding protein, hydrolyze ATP independently from any signal. The data are compatible with the notion that cross-membrane signaling between the liganded periplasmic receptor and the cytoplasmic ATP-binding sites initiates conformational changes leading to ATP hydrolysis and substrate translocation.