title: Identification of the clpB and bipA genes and an evaluation of their expression as related to intracellular survival for the bacterial pathogen Piscirickettsia salmonis.
abstract: Piscirickettsia salmonis is the pathogen responsible for salmonid rickettsial septicemia (SRS), a disease that affects a wide variety of marine cultivated fish species and causes economic losses for the aquaculture industry worldwide. Many in vitro studies have reported on the capacity of this microorganism to replicate in the interior of cytoplasmic vesicles from varied fish cell lines. However, the mechanisms used by this bacteria to survive, replicate, and propagate in cell lines, especially in macrophages and monocytes, are unknown. A number of studies have described the diverse proteins in pathogens such as Legionella pneumophila, Coxiella burnetii, and Francisella tularensis which allow these to evade the cellular immune response and replicate in the interior of macrophages in different hosts. Some of these proteins are the virulence factor BipA/TypA and the heat shock protein ClpB, both of which have been widely characterized. The results of the current study present the complete coding sequence of the genes clpB and bipA from the P. salmonis genome. Moreover, the experimental results suggest that during the infectious process of the SHK-1 cellular line in P. salmonis, the pathogen significantly increases the expression of proteins ClpB and BipA. This would permit the pathogen to adapt to the hostile conditions produced by the macrophage and thus evade mechanisms of cellular degradation while facilitating replication in the interior of this salmon cell line.
authors.affiliation: Instituto de Bioquímica y Microbiología, F. de Ciencias, U. Austral de Chile, Valdivia, Chile; Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile.
authors.forename: A
authors.initials: A
authors.lastname: Isla
authors.affiliation: Instituto de Bioquímica y Microbiología, F. de Ciencias, U. Austral de Chile, Valdivia, Chile.
authors.forename: D
authors.initials: D
authors.lastname: Haussmann
authors.affiliation: Instituto de Bioquímica y Microbiología, F. de Ciencias, U. Austral de Chile, Valdivia, Chile; Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile.
authors.forename: T
authors.initials: T
authors.lastname: Vera
authors.affiliation: Instituto de Bioquímica y Microbiología, F. de Ciencias, U. Austral de Chile, Valdivia, Chile.
authors.forename: G
authors.initials: G
authors.lastname: Kausel
authors.affiliation: Instituto de Bioquímica y Microbiología, F. de Ciencias, U. Austral de Chile, Valdivia, Chile; Centro FONDAP, Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile. Electronic address: jefigueroa@uach.cl.
authors.forename: J
authors.initials: J
authors.lastname: Figueroa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017756:Aquaculture; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D002460:Cell Line; D019295:Computational Biology; D017124:Conserved Sequence / Q000235:genetics; D005393:Fish Diseases / Q000382:microbiology*; D005786:Gene Expression Regulation / Q000502:physiology*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D053522:Piscirickettsia / Q000235:genetics* / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012288:Rickettsiaceae Infections / Q000662:veterinary*; D012487:Salmonidae; D017422:Sequence Analysis, DNA / Q000662:veterinary; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D006360:Heat-Shock Proteins; D037521:Virulence Factors
keywords: ClpB and bipA; Fish pathogen; Piscirickettsia salmonis; SRS