The covalent complex of Jo-In results from a long-lived, non-covalent intermediate state with near-native structure

• Published in: Biochemical and biophysical research communications Vol. 589; pp. 223 - 228
• Main Authors: Cox, Neil, Charlier, Cyril, Vijayaraj, Ramadoss, De La Mare, Marion, Barbe, Sophie, André, Isabelle, Lippens, Guy, Montanier, Cédric Y.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 22.01.2022; Elsevier
• Subjects: Amino Acids - metabolism; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; Biochemistry, Molecular Biology; Biomolecular welding tool; Jo-in; Life Sciences; Molecular modelling; Multiprotein Complexes - chemistry; Multiprotein Complexes - metabolism; NMR; Protein Binding; Protein Stability; Proton Magnetic Resonance Spectroscopy; Streptococcus pneumoniae - metabolism; Biomolecular welding tool; Jo-in; NMR; Molecular modelling
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2021.12.028

Covalent protein complexes have been used to assemble enzymes in large scaffolds for biotechnology purposes. Although the catalytic mechanism of the covalent linking of such proteins is well known, the recognition and overall structural mechanisms driving the association are far less understood but could help further functional engineering of these complexes. Here, we study the Jo-In complex by NMR spectroscopy and molecular modelling. We characterize a transient non-covalent complex, with structural elements close to those in the final covalent complex. Using site specific mutagenesis, we further show that this non-covalent association is essential for the covalent complex to form. •The covalent bond formation is not essential for Jo-In interaction.•A specific couple of amino acids at the Jo/In interface is engaged in the recognition and the stabilisation of the complex.•A transient complex formation is required for covalent bond formation between Jo and In.