6u6p

Publication Abstract from PubMed

Bacterial MinD and MinE form a standing oscillatory wave which positions the cell division inhibitor MinC, that binds MinD, everywhere on the membrane except at the midpoint of the cell, ensuring midcell positioning of the cytokinetic septum. During this process MinE undergoes fold switching as it interacts with different partners. We explore the exchange dynamics between major and excited states of the MinE dimer in 3 forms using (15)N relaxation dispersion NMR: the full-length protein (6-stranded beta-sheet sandwiched between 4 helices) representing the resting state; a 10-residue N-terminal deletion (Delta10) mimicking the membrane-binding competent state where the N-terminal helix is detached to interact with membrane; and N-terminal deletions of either 30 (Delta30) or 10 residues with an I24N mutation (Delta10/I24N), in which the beta1-strands at the dimer interface are extruded and available to bind MinD, leaving behind a 4-stranded beta-sheet. Full-length MinE samples 2 "excited" states: The first is similar to a full-length/Delta10 heterodimer; the second, also sampled by Delta10, is either similar to or well along the pathway toward the 4-stranded beta-sheet form. Both Delta30 and Delta10/I24N sample 2 excited species: The first may involve destabilization of the beta3- and beta3'-strands at the dimer interface; changes in the second are more extensive, involving further disruption of secondary structure, possibly representing an ensemble of states on the pathway toward restoration of the resting state. The quantitative information on MinE conformational dynamics involving these excited states is crucial for understanding the oscillation pattern self-organization by MinD-MinE interaction dynamics on the membrane.

Probing transient excited states of the bacterial cell division regulator MinE by relaxation dispersion NMR spectroscopy.,Cai M, Huang Y, Shen Y, Li M, Mizuuchi M, Ghirlando R, Mizuuchi K, Clore GM Proc Natl Acad Sci U S A. 2019 Dec 17;116(51):25446-25455. doi:, 10.1073/pnas.1915948116. Epub 2019 Nov 26. PMID:31772021^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.