title: The Streptomyces lividans cytoplasmic signal recognition particle receptor FtsY is involved in protein secretion.
abstract: The bacterial version of the mammalian signal recognition particle (SRP) and its receptor alpha-subunit (FtsY) is well conserved and essential to all known bacteria. In gram-negative bacteria, the SRP pathway mediates a co-translational targeting of most inner membrane proteins. Additionally, in Streptomyces lividans, a gram-positive bacterium, SRP also targets secretory proteins to the translocon. The role of S. lividans FtsY has been assessed in this work. Co-immunoprecipitation studies confirmed that FtsY is associated with the S. lividans SRP in the cytoplasm and that this complex also co-immunoprecipitated with pre-agarase, suggesting that the SRP receptor is involved in SRP-mediated targeting of secretory proteins in S. lividans. Furthermore, the SRP remains attached for the most part to the cellular membrane when the cleavage of pre-secretory proteins is severely reduced in a strain lacking the gene coding for the major type-I signal peptidase.
authors.affiliation: Centro Nacional de Biotecnología, Campus de la Universidad Autónoma, Cantoblanco, Madrid, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Palomino
authors.forename: Rafael P
authors.initials: RP
authors.lastname: Mellado
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D002462:Cell Membrane / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D047468:Immunoprecipitation; D008954:Models, Biological; D011485:Protein Binding; D021381:Protein Transport; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D018271:Signal Recognition Particle / Q000378:metabolism; D048170:Streptomyces lividans / Q000235:genetics / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; C087406:FtsY protein, Bacteria; D018160:Receptors, Cytoplasmic and Nuclear; D018271:Signal Recognition Particle