Fig. 1: LarA binds specifically to the NTD of C. crescentus Lon.
From: Structural basis for the allosteric activation of Lon by the heat shock protein LarA
a Cartoon illustrating the composition of the protein constructs. NTD (green), LH (yellow), AAA (orange), and Protease (red) represent the N-terminal domain, long helices, ATPases Associated with diverse cellular Activities (AAA + ) domain, and protease domain of CcLon, respectively. DUF (pink) is a domain of unknown function. HTH (grey) is helix-turn-helix. b Surface representations in side (left) and top (right) views of a hexameric Lon in a substrate-free state (PDB code 7YUX). Each protomer is colored differently. One protomer is shown in ribbons. Due to the linker between the LH and AAA domains (red oval), three of the NTDs (NTD*) are rotationally flexible. c, d Chromatograms of Superose 6 size-exclusion chromatography of full-length CcLon (c) and CcLonΔ206 (d), with or without the presence of LarA. The curves of CcLon/CcLonΔ206, LarA, and protein mixtures are labeled with black, red, and blue, respectively. e Degradation of LarA and SciP by CcLon. An ATP regeneration system using ATP, creatine phosphate, and creatine kinase (CK) was included in the reactions. f No ATP-dependent degradation of LarA or SciP by CcLonΔ206. g Chromatogram of Superdex 75 size-exclusion chromatography of purified LarA-NTD complex. SDS-PAGE and Coomassie staining were used to analyze selected chromatographic fractions and the in vitro reactions. The gels and curves (c–g) shown are representative of three independent experiments with consistent results. Source data are provided as a Source Data file.
