title: Structural representative of the protein family PF14466 has a new fold and establishes links with the C2 and PLAT domains from the widely distant Pfams PF00168 and PF01477.
abstract: The domain of unknown function (DUF) YP_001302112.1, a protein secreted by the human intestinal microbita, has been determined by NMR and represents the first structure for the Pfam PF14466. Its NMR structure is classified as a new fold, which, nonetheless, shows limited similarities with representatives of the PLAT/LH2 domains from PF01477 and the C2 domains from PF00168, both of which bind Ca(2+) for their physiological functions. Further experiments revealed affinity of YP_001302112.1 for Ca(2+), and the NMR structure in the presence of CaCl2 was better defined than that of the apo-protein. Overall, these NMR structures establish a new connection between structural representatives from two widely different Pfams that include the calcium-binding domain of a sialidase from Vibrio cholerae and the α-toxin from Clostridium perfrigens, whereby these two proteins have only 7% sequence identity. Furthermore, it provides information toward the functional annotation of YP_001302112.1, based on its capacity to bind Ca(2+), and thus adds to the structural and functional coverage of the protein sequence universe.
authors.affiliation: Joint Center for Structural Genomics, La Jolla, California, USA.
authors.forename: Pedro
authors.initials: P
authors.lastname: Serrano
authors.forename: Michael
authors.initials: M
authors.lastname: Geralt
authors.forename: Biswaranjan
authors.initials: B
authors.lastname: Mohanty
authors.forename: Kurt
authors.initials: K
authors.lastname: Wüthrich
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D003016:Clostridium perfringens / Q000737:chemistry / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000382:microbiology; D006801:Humans; D064307:Microbiota; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary; D014734:Vibrio cholerae / Q000737:chemistry / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002135:Calcium-Binding Proteins