2WPW

Tandem GNAT protein from the clavulanic acid biosynthesis pathway (without AcCoA)

Summary for 2WPW

• Entry DOI: 10.2210/pdb2wpw/pdb
• Related: 2WPX
• Descriptor: ORF14, ACETYL COENZYME *A (3 entities in total)
• Functional Keywords: transferase, acetyl transferase, antibiotic biosynthesis
• Biological source: STREPTOMYCES CLAVULIGERUS
• Total number of polymer chains: 4
• Total formula weight: 149898.18

Authors

Iqbal, A.,Arunlanantham, H.,McDonough, M.A.,Chowdhury, R.,Clifton, I.J. (deposition date: 2009-08-11, release date: 2009-12-29, Last modification date: 2024-11-13)

Primary citation

Iqbal, A.,Arunlanantham, H.,Brown, T.,Chowdhury, R.,Clifton, I.J.,Kershaw, N.J.,Hewitson, K.S.,McDonough, M.A.,Schofield, C.J.
Crystallographic and mass spectrometric analyses of a tandem GNAT protein from the clavulanic acid biosynthesis pathway.
Proteins, 78:1398-1407, 2010

PubMed Abstract: (3R,5R)-Clavulanic acid (CA) is a clinically important inhibitor of Class A beta-lactamases. Sequence comparisons suggest that orf14 of the clavulanic acid biosynthesis gene cluster encodes for an acetyl transferase (CBG). Crystallographic studies reveal CBG to be a member of the emerging structural subfamily of tandem Gcn5-related acetyl transferase (GNAT) proteins. Two crystal forms (C2 and P2(1) space groups) of CBG were obtained; in both forms one molecule of acetyl-CoA (AcCoA) was bound to the N-terminal GNAT domain, with the C-terminal domain being unoccupied by a ligand. Mass spectrometric analyzes on CBG demonstrate that, in addition to one strongly bound AcCoA molecule, a second acyl-CoA molecule can bind to CBG. Succinyl-CoA and myristoyl-CoA displayed the strongest binding to the "second" CoA binding site, which is likely in the C-terminal GNAT domain. Analysis of the CBG structures, together with those of other tandem GNAT proteins, suggest that the AcCoA in the N-terminal GNAT domain plays a structural role whereas the C-terminal domain is more likely to be directly involved in acetyl transfer. The available crystallographic and mass spectrometric evidence suggests that binding of the second acyl-CoA occurs preferentially to monomeric rather than dimeric CBG. The N-terminal AcCoA binding site and the proposed C-terminal acyl-CoA binding site of CBG are compared with acyl-CoA binding sites of other tandem and single domain GNAT proteins.

PubMed: 20014241
DOI: 10.1002/prot.22653

Experimental method

X-RAY DIFFRACTION (2.38 Å)