Trimeric structure and conformational equilibrium of M-ficolin fibrinogen-like domain.

ABSTRACT: Ficolins are pathogen-recognition molecules in innate immune systems. The crystal structure of the human M-ficolin recognition domain (FD1) has been determined at 1.9 A resolution, and compared with that of the human fibrinogen gamma fragment, tachylectin-5A, L-ficolin and H-ficolin. The overall structure of FD1 is similar to that of the other proteins, although the peptide bond between Asp282 and Cys283, which is in a predicted ligand-binding site, is a normal trans bond, unlike the cases of the other proteins. Analysis of the pH-dependent ligand-binding activity of FD1 in solution suggested that a conformational equilibrium between active and non-active forms in the ligand-binding region, involving cis-trans isomerization of the Asp282-Cys283 peptide bond, contributes to the discriminati

SUBMITTER: Tanio M 

PROVIDER: S-EPMC2394802 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature