Solution structure of Archaeglobus fulgidis peptidyl-tRNA hydrolase (Pth2) provides evidence for an extensive conserved family of Pth2 enzymes in archea, bacteria, and eukaryotes.

TitleSolution structure of Archaeglobus fulgidis peptidyl-tRNA hydrolase (Pth2) provides evidence for an extensive conserved family of Pth2 enzymes in archea, bacteria, and eukaryotes.
Publication TypeJournal Article
Year of Publication2005
AuthorsPowers, R, Mirkovic, N, Goldsmith-Fischman, S, Acton, TB, Chiang, Y, Huang, YJ, Ma, L, Rajan, PK, Cort, JR, Kennedy, MA, Liu, J, Rost, B, Honig, B, Murray, D, Montelione, GT
JournalProtein Sci
Volume14
Issue11
Pagination2849-61
Date Published2005 Nov
ISSN0961-8368
KeywordsArchaea, Archaeal Proteins, Archaeoglobus fulgidus, Bacteria, Binding Sites, Carboxylic Ester Hydrolases, Conserved Sequence, Evolution, Molecular, Humans, Models, Molecular, Nuclear Magnetic Resonance, Biomolecular, Phylogeny, Sequence Homology, Amino Acid, Solutions, Structural Homology, Protein
Abstract

The solution structure of protein AF2095 from the thermophilic archaea Archaeglobus fulgidis, a 123-residue (13.6-kDa) protein, has been determined by NMR methods. The structure of AF2095 is comprised of four alpha-helices and a mixed beta-sheet consisting of four parallel and anti-parallel beta-strands, where the alpha-helices sandwich the beta-sheet. Sequence and structural comparison of AF2095 with proteins from Homo sapiens, Methanocaldococcus jannaschii, and Sulfolobus solfataricus reveals that AF2095 is a peptidyl-tRNA hydrolase (Pth2). This structural comparison also identifies putative catalytic residues and a tRNA interaction region for AF2095. The structure of AF2095 is also similar to the structure of protein TA0108 from archaea Thermoplasma acidophilum, which is deposited in the Protein Data Bank but not functionally annotated. The NMR structure of AF2095 has been further leveraged to obtain good-quality structural models for 55 other proteins. Although earlier studies have proposed that the Pth2 protein family is restricted to archeal and eukaryotic organisms, the similarity of the AF2095 structure to human Pth2, the conservation of key active-site residues, and the good quality of the resulting homology models demonstrate a large family of homologous Pth2 proteins that are conserved in eukaryotic, archaeal, and bacterial organisms, providing novel insights in the evolution of the Pth and Pth2 enzyme families.

DOI10.1110/ps.051666705
Alternate JournalProtein Sci.
PubMed ID16251366
PubMed Central IDPMC2253226
Grant ListP50 GM 62413 / GM / NIGMS NIH HHS / United States