3CI4

Structure of the PduO-type ATP:co(I)rrinoid adenosyltransferase from Lactobacillus reuteri complexed with four-coordinate cob(II)inamide and ATP

Summary for 3CI4

• Entry DOI: 10.2210/pdb3ci4/pdb
• Related: 2NT8 3CI1 3CI3
• Descriptor: Cobalamin adenosyltransferase PduO-like protein, POTASSIUM ION, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: adenosyltransferase variant, atp binding, corrin binding, transferase
• Biological source: Lactobacillus reuteri
• Total number of polymer chains: 1
• Total formula weight: 23942.99

Authors

Maurice, M.St.,Mera, P.E.,Escalante-Semerena, J.C.,Rayment, I. (deposition date: 2008-03-10, release date: 2008-05-27, Last modification date: 2024-02-21)

Primary citation

St Maurice, M.,Mera, P.,Park, K.,Brunold, T.C.,Escalante-Semerena, J.C.,Rayment, I.
Structural characterization of a human-type corrinoid adenosyltransferase confirms that coenzyme B12 is synthesized through a four-coordinate intermediate.
Biochemistry, 47:5755-5766, 2008

PubMed Abstract: ATP:cob(I)alamin adenosyltransferases (ACAs) catalyze the transfer of the 5'-deoxyadenosyl moiety from ATP to the upper axial ligand position of cobalamin in the synthesis of coenzyme B 12. For the ACA-catalyzed reaction to proceed, cob(II)alamin must be reduced to cob(I)alamin in the enzyme active site. This reduction is facilitated through the generation of a four-coordinate cob(II)alamin intermediate on the enzyme. We have determined the high-resolution crystal structure of a human-type ACA from Lactobacillus reuteri with a four-coordinate cob(II)alamin bound in the enzyme active site and with the product, adenosylcobalamin, partially occupied in the active site. The assembled structures represent snapshots of the steps in the ACA-catalyzed formation of the cobalt-carbon bond of coenzyme B 12. The structures define the corrinoid binding site and provide visual evidence for a base-off, four-coordinate cob(II)alamin intermediate. The complete structural description of ACA-mediated catalysis reveals the molecular features of four-coordinate cob(II)alamin stabilization and provides additional insights into the molecular basis for dysfunction in human patients suffering from methylmalonic aciduria.

PubMed: 18452306
DOI: 10.1021/bi800132d

Experimental method

X-RAY DIFFRACTION (2 Å)