The conserved crown bridge loop at the catalytic centre of enzymes of the haloacid dehalogenase superfamily.

ABSTRACT: The crown bridge loop is hexapeptide motif in which the backbone carbonyl group at position 1 is hydrogen bonded to the backbone imino groups of positions 4 and 6. Residues at positions 1 and 4-6 are held in a tight substructure, but different orientations of the plane of the peptide bond between positions 2 and 3 result in two conformers: the 2,3-α_Rα_R crown bridge loop - found in approximately 7% of proteins - and the 2,3-β_Rα_L crown bridge loop, found in approximately 1-2% of proteins. We constructed a relational database in which we identified 60 instances of the 2,3-β_Rα_L conformer, and find that about half occur in enzymes of the haloacid dehalogenase (HAD) superfamily, where they are located next to the catalytic asparta

SUBMITTER: Leader DP 

PROVIDER: S-EPMC10541634 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature