Structure of Arabidopsis thaliana At1g77540 Protein, a Minimal Acetyltransferase from the COG2388 Family.Tyler, R.C., Bitto, E., Berndsen, C.E., Bingman, C.A., Singh, S., Lee, M.S., Wesenberg, G.E., Denu, J.M., Phillips Jr., G.N., Markley, J.L.
(2006) Biochemistry 45: 14325-14336
- PubMed: 17128971
- DOI: 10.1021/bi0612059
- Primary Citation of Related Structures:
2EVN, 2IL4, 1XMT
- PubMed Abstract:
We describe X-ray crystal and NMR solution structures of the protein coded for by Arabidopsis thaliana gene At1g77540.1 (At1g77540). The crystal structure was determined to 1.15 A with an R factor of 14.9% (Rfree = 17.0%) by multiple-wavelength anoma ...
We describe X-ray crystal and NMR solution structures of the protein coded for by Arabidopsis thaliana gene At1g77540.1 (At1g77540). The crystal structure was determined to 1.15 A with an R factor of 14.9% (Rfree = 17.0%) by multiple-wavelength anomalous diffraction using sodium bromide derivatized crystals. The ensemble of NMR conformers was determined with protein samples labeled with 15N and 13C + 15N. The X-ray structure and NMR ensemble were closely similar with rmsd 1.4 A for residues 8-93. At1g77540 was found to adopt a fold similar to that of GCN5-related N-acetyltransferases. Enzymatic activity assays established that At1g77540 possesses weak acetyltransferase activity against histones H3 and H4. Chemical shift perturbations observed in 15N-HSQC spectra upon the addition of CoA indicated that the cofactor binds and identified its binding site. The molecular details of this interaction were further elucidated by solving the X-ray structure of the At1g77540-CoA complex. This work establishes that the domain family COG2388 represents a novel class of acetyltransferase and provides insight into possible mechanistic roles of the conserved Cys76 and His41 residues of this family.
Center for Eukaryotic Structural Genomics, Biochemistry Department, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706-1544, USA.