Open AccessThree-dimensional profiles from residue-pair preferences: identification of sequences with beta/alpha-barrel fold.
Author(s) -
Matthias Wilmanns,
David Eisenberg
Publication year - 1993
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.90.4.1379
Subject(s) - residue (chemistry) , protein secondary structure , stereochemistry , chemistry , amino acid , glutamine amidotransferase , protein structure , glutamine , biochemistry
The three-dimensional profile method expresses the three-dimensional structure of a protein as a table, the profile, which represents the local environment of each residue. The score of an amino acid sequence, aligned with the three-dimensional profile, reflects its compatibility with the profiled structure. In the original implementation, each local environment was characterized by its polarity, the area buried of its side chain, and its secondary structure. Here we describe a modified three-dimensional profile algorithm that characterizes the local environment in terms of the statistical preferences of the profiled residue for neighbors of specific residue types, main-chain conformations, or secondary structure. Combined profiles of the original and the three new types were tested on beta/alpha-barrel protein structures. The method identified the following enzymes of unknown three-dimensional structure as probable beta/alpha-barrels, all of which catalyze reactions in the biosynthesis of aromatic amino acids: anthranilate phosphoribosyltransferase (trpD), glutamine amidotransferase (trpG), and phosphoribosylformimino-5-aminoimidazole carboxamide ribotide isomerase (hisA).