7cay

Publication Abstract from PubMed

LonA peptidase is a major component of the protein quality-control mechanism in both prokaryotes and the organelles of eukaryotes. Proteins homologous to the N-terminal domain of LonA peptidase, but lacking its other domains, are conserved in several phyla of prokaryotes, including the Xanthomonadales order. However, the function of these homologous proteins (LonNTD-like proteins) is not known. Here, the crystal structure of the LonNTD-like protein from Xanthomonas campestris (XCC3289; UniProt Q8P5P7) is reported at 2.8 A resolution. The structure was solved by molecular replacement and contains one polypeptide in the asymmetric unit. The structure was refined to an Rfree of 29%. The structure of XCC3289 consists of two domains joined by a long loop. The N-terminal domain (residues 1-112) consists of an alpha-helix surrounded by beta-sheets, whereas the C-terminal domain (residues 123-193) is an alpha-helical bundle. The fold and spatial orientation of the two domains closely resembles those of the N-terminal domains of the LonA peptidases from Escherichia coli and Mycobacterium avium. The structure is also similar to that of cereblon, a substrate-recognizing component of the E3 ubiquitin ligase complex. The N-terminal domains of both LonA and cereblon are known to be involved in specific protein-protein interactions. This structural analysis suggests that XCC3289 and other LonNTD-like proteins might also be capable of such protein-protein interactions.

Crystal structure of XCC3289 from Xanthomonas campestris: homology with the N-terminal substrate-binding domain of Lon peptidase.,Singh R, Deshmukh S, Kumar A, Goyal VD, Makde RD Acta Crystallogr F Struct Biol Commun. 2020 Oct 1;76(Pt 10):488-494. doi:, 10.1107/S2053230X20011875. Epub 2020 Sep 16. PMID:33006577^[1]

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