1X2H

Crystal Structure of Lipate-Protein Ligase A from Escherichia coli complexed with lipoic acid

Summary for 1X2H

• Entry DOI: 10.2210/pdb1x2h/pdb
• Related: 1X2G
• Descriptor: Lipoate-protein ligase A, LIPOIC ACID (3 entities in total)
• Functional Keywords: lipoate-protein ligase, lipoic acid, protein acylation, post-translational modification, ligase
• Biological source: Escherichia coli
• Cellular location: Cytoplasm: P32099
• Total number of polymer chains: 3
• Total formula weight: 114637.95

Authors

Fujiwara, K.,Toma, S.,Okamura-Ikeda, K.,Motokawa, Y.,Nakagawa, A.,Taniguchi, H. (deposition date: 2005-04-23, release date: 2005-08-02, Last modification date: 2024-10-16)

Primary citation

Fujiwara, K.,Toma, S.,Okamura-Ikeda, K.,Motokawa, Y.,Nakagawa, A.,Taniguchi, H.
Crystal structure of lipoate-protein ligase A from Escherichia coli: Determination of the lipoic acid-binding site
J.Biol.Chem., 280:33645-33651, 2005

PubMed Abstract: Lipoate-protein ligase A (LplA) catalyzes the formation of lipoyl-AMP from lipoate and ATP and then transfers the lipoyl moiety to a specific lysine residue on the acyltransferase subunit of alpha-ketoacid dehydrogenase complexes and on H-protein of the glycine cleavage system. The lypoyllysine arm plays a pivotal role in the complexes by shuttling the reaction intermediate and reducing equivalents between the active sites of the components of the complexes. We have determined the X-ray crystal structures of Escherichia coli LplA alone and in a complex with lipoic acid at 2.4 and 2.9 angstroms resolution, respectively. The structure of LplA consists of a large N-terminal domain and a small C-terminal domain. The structure identifies the substrate binding pocket at the interface between the two domains. Lipoic acid is bound in a hydrophobic cavity in the N-terminal domain through hydrophobic interactions and a weak hydrogen bond between carboxyl group of lipoic acid and the Ser-72 or Arg-140 residue of LplA. No large conformational change was observed in the main chain structure upon the binding of lipoic acid.

PubMed: 16043486
DOI: 10.1074/jbc.M505010200

Experimental method

X-RAY DIFFRACTION (2.91 Å)