MS09-P14 Allosteric Coupling between Autophosphorylation and Phosphoryl-group transfer in a Prototypical Two-Component Signal Transduction System Ariel Mechaly (Plateforme de Cristallographie, Institut Pasteur, Paris, France) Pedro Alzari (Unite de Microbiologie Structurale, Institut Pasteur, Paris, France) Jean-Michel Betton (Unite de Microbiologie Structurale, Institut Pasteur, Paris, France) Alejandro Buschiazzo (Laboratory of Molecular and Structural Microbiology, Institut Pasteur de Montevideo, Montevideo, Uruguay) Ahmed Haouz (Plateforme de Cristallographie, Plateforme de Cristallographie, Paris, France) Nathalie Sassoon (Unite de Microbiologie Structurale, Institut Pasteur, Paris, France) Silvia Soto-Diaz (Unite de Microbiologie Structurale, Institut Pasteur, Paris, France)email: ariel.mechaly@pasteur.fr

Prototypical two-component signal transduction systems comprises a sensor histidine kinase (HK) receptor and a response regulator (RR). Input signals induce sensor HK autophosphorylation, and the subsequent transfer of the phosphoryl-group to the RR. Upon receiving the phosphoryl-group, the RR triggers an adaptive response, often at the transcriptional level. To gain insights into how the autokinase and phosphotransferase activities of the sensor HK are coordinated, we solved structures of the catalytic core domains of the prototypical CpxA-CpxR system [1]. Our data suggest a concerted switch -involving large-scale domain motions- by which autophosphorylation and phosphotransfer reactions are allosterically coupled.

References:

Mechaly, A.E., Soto Diaz, S., Sassoon, N., Buschiazzo, A., Betton, J.M., and Alzari, P.M. (2017). Structural Coupling between Autokinase and Phosphotransferase Reactions in a Bacterial Histidine Kinase. Structure 25, 939-944 e933.
Keywords: Histidine kinase, Response regulator, phosphotrasfer