Conformational Domain Wall Switch

N-terminal domain of alphaB-crystallin provides a conformational switch for multimerization and structural heterogeneity.

The small heat shock protein (sHSP) αB-crystallin (αB) plays a key role in the cellular protection system against stress. For decades, high-resolution structural studies on heterogeneous sHSPs have been confounded by the polydisperse nature of αB oligomers. We present an atomic-level model of full-length αB as a symmetric 24-subunit multimer based on solid-state NMR, small-angle X-ray scatterin...

Mapping L1 ligase ribozyme conformational switch.

L1 ligase (L1L) molecular switch is an in vitro optimized synthetic allosteric ribozyme that catalyzes the regioselective formation of a 5'-to-3' phosphodiester bond, a reaction for which there is no known naturally occurring RNA catalyst. L1L serves as a proof of principle that RNA can catalyze a critical reaction for prebiotic RNA self-replication according to the RNA world hypothesis. L1L cr...

EPR spectroscopy shows a microtubule-dependent conformational change in the kinesin switch 1 domain.

We have used site-directed spin-labeling and electron paramagnetic resonance spectroscopy to monitor a conformational change at the nucleotide site of kinesin. Cys-lite kinesin (K349 monomer) with the mutation S188C was spin labeled with MSL or MTSL. This residue is at the junction between the switch 1 region (which is a structure known to be sensitive to bound nucleotide in the G-proteins) and...

Pro-Gly mediated conformational switch of mycobacteriophage D29 holin transmembrane domain I is lipid concentration driven.

Biophysical and spectroscopic analysis of synthetic transmembrane domain I (1) of mycobacteriophage D29 holin shows a lipid concentration dependent conformational switch from an α-helix to a β-sheet structure. The reversibility of this switch, upon change in the lipid-to-peptide ratio, requires a central Pro-Gly segment, and is abolished upon mutation to Ala-Ala or (D)Pro-Gly.

Structures of NLRP14 pyrin domain reveal a conformational switch mechanism, regulating its molecular interactions