3F8K

Crystal structure of protein acetyltransferase (PAT) from Sulfolobus solfataricus

Summary for 3F8K

• Entry DOI: 10.2210/pdb3f8k/pdb
• Descriptor: Protein acetyltransferase, COENZYME A (3 entities in total)
• Functional Keywords: gcn5-related n-acetyltransferase, transferase
• Biological source: Sulfolobus solfataricus P2
• Total number of polymer chains: 1
• Total formula weight: 19586.41

Authors

Brent, M.M. (deposition date: 2008-11-12, release date: 2009-05-26, Last modification date: 2024-10-30)

Primary citation

Brent, M.M.,Iwata, A.,Carten, J.,Zhao, K.,Marmorstein, R.
Structure and Biochemical Characterization of Protein Acetyltransferase from Sulfolobus solfataricus.
J.Biol.Chem., 284:19412-19419, 2009

PubMed Abstract: The Sulfolobus solfataricus protein acetyltransferase (PAT) acetylates ALBA, an abundant nonspecific DNA-binding protein, on Lys(16) to reduce its DNA affinity, and the Sir2 deacetylase reverses the modification to cause transcriptional repression. This represents a "primitive" model for chromatin regulation analogous to histone modification in eukaryotes. We report the 1.84-A crystal structure of PAT in complex with coenzyme A. The structure reveals homology to both prokaryotic GNAT acetyltransferases and eukaryotic histone acetyltransferases (HATs), with an additional "bent helix" proximal to the substrate binding site that might play an autoregulatory function. Investigation of active site mutants suggests that PAT does not use a single general base or acid residue for substrate deprotonation and product reprotonation, respectively, and that a diffusional step, such as substrate binding, may be rate-limiting. The catalytic efficiency of PAT toward ALBA is low relative to other acetyltransferases, suggesting that there may be better, unidentified substrates for PAT. The structural similarity of PAT to eukaryotic HATs combined with its conserved role in chromatin regulation suggests that PAT is evolutionarily related to the eukaryotic HATs.

PubMed: 19473964
DOI: 10.1074/jbc.M109.014951

Experimental method

X-RAY DIFFRACTION (1.84 Å)