title: FeeM, an N-acyl amino acid synthase from an uncultured soil microbe: structure, mechanism, and acyl carrier protein binding.
abstract: Attempts to access antibiotics by capturing biosynthetic genes and pathways directly from environmental DNA, which is overwhelmingly derived from uncultured bacteria, have revealed a large and previously unknown family of N-acyl amino acid synthases (NASs). The structure of the NAS FeeM reveals structural similarity to the GCN5-related N-acyl transferases and acylhomoserine lactone synthases. The overall structure has a central beta sheet with alpha helices on both sides. A bound product at a cleft in the beta sheet identifies the active site and the structural basis for catalysis, and sequence conservation in this region indicates a bias for recognition over speed. FeeM interacts with an acyl carrier protein (FeeL), and the structure, mutagenesis, and enzymatic measurements reveal that a small hydrophobic pocket in alpha helix 5 dominates binding of FeeM to FeeL. The structural and mechanistic analyses suggest that the products of FeeM could be bacterial signaling agents.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Van Wagoner
authors.forename: Jon
authors.initials: J
authors.lastname: Clardy
mesh_terms: D000213:Acyl Carrier Protein / Q000378:metabolism*; D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D008025:Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D012988:Soil Microbiology
chemical_list: D000213:Acyl Carrier Protein; D008025:Ligases