title: A putative serine protease, SpSsp1, from Saprolegnia parasitica is recognised by sera of rainbow trout, Oncorhynchus mykiss.
abstract: Saprolegniosis, the disease caused by Saprolegnia sp., results in considerable economic losses in aquaculture. Current control methods are inadequate, as they are either largely ineffective or present environmental and fish health concerns. Vaccination of fish presents an attractive alternative to these control methods. Therefore we set out to identify suitable antigens that could help generate a fish vaccine against Saprolegnia parasitica. Unexpectedly, antibodies against S. parasitica were found in serum from healthy rainbow trout, Oncorhynchus mykiss. The antibodies detected a single band in secreted proteins that were run on a one-dimensional SDS-polyacrylamide gel, which corresponded to two protein spots on a two-dimensional gel. The proteins were analysed by liquid chromatography tandem mass spectrometry. Mascot and bioinformatic analysis resulted in the identification of a single secreted protein, SpSsp1, of 481 amino acid residues, containing a subtilisin domain. Expression analysis demonstrated that SpSsp1 is highly expressed in all tested mycelial stages of S. parasitica. Investigation of other non-infected trout from several fish farms in the United Kingdom showed similar activity in their sera towards SpSsp1. Several fish that had no visible saprolegniosis showed an antibody response towards SpSsp1 suggesting that SpSsp1 might be a useful candidate for future vaccination trial experiments.
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: Kirsty L
authors.initials: KL
authors.lastname: Minor
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Anderson
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: Katie S
authors.initials: KS
authors.lastname: Davis
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: Albert H
authors.initials: AH
authors.lastname: Van Den Berg
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: James S
authors.initials: JS
authors.lastname: Christie
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
authors.forename: Lars
authors.initials: L
authors.lastname: Löbach
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK; Department of Aquaculture, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Faruk
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
authors.forename: Stephan
authors.initials: S
authors.lastname: Wawra
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Secombes
authors.affiliation: Aberdeen Oomycete Laboratory, College of Life Sciences and Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK. Electronic address: p.vanwest@abdn.ac.uk.
authors.forename: Pieter
authors.initials: P
authors.lastname: Van West
mesh_terms: D000818:Animals; D000906:Antibodies / Q000097:blood*; D000941:Antigens / Q000276:immunology*; D017756:Aquaculture; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D017686:Oncorhynchus mykiss / Q000276:immunology*; D044762:Saprolegnia / Q000201:enzymology*; D057057:Serine Proteases / Q000276:immunology*; D053719:Tandem Mass Spectrometry; D006113:United Kingdom
chemical_list: D000906:Antibodies; D000941:Antigens; D057057:Serine Proteases
keywords: Oncorhynchus mykiss; Pathogenicity factor; Saprolegnia parasitica; Serine protease
references.citation: J Fish Dis. 2005 Aug;28(8):445-53
references.pmid: 16159362
references.citation: Electrophoresis. 1993 Oct;14(10):1023-31
references.pmid: 8125050
references.citation: Bioinformatics. 2007 Nov 1;23(21):2947-8
references.pmid: 17846036
references.citation: Dis Aquat Organ. 2009 Jan 28;83(1):17-22
references.pmid: 19301632
references.citation: Mol Immunol. 2007 Mar;44(9):2303-14
references.pmid: 17204328
references.citation: Dev Comp Immunol. 2012 Sep;38(1):44-54
references.pmid: 22522286
references.citation: Infect Immun. 1993 Jun;61(6):2357-68
references.pmid: 8500876
references.citation: Mycopathologia. 2005 Feb;159(2):231-43
references.pmid: 15770449
references.citation: Plant Cell. 1998 Sep;10(9):1413-26
references.pmid: 9724689
references.citation: Mol Biol Evol. 2007 Aug;24(8):1596-9
references.pmid: 17488738
references.citation: Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
references.pmid: 9254694
references.citation: Nucleic Acids Res. 2007 Jan;35(Database issue):D237-40
references.pmid: 17135202
references.citation: Dis Aquat Organ. 2007 Feb 28;74(2):107-11
references.pmid: 17432039
references.citation: Fish Shellfish Immunol. 2010 Nov;29(5):753-8
references.pmid: 20624467
references.citation: Aquat Toxicol. 2004 Feb 25;66(3):319-29
references.pmid: 15129773
references.citation: J Mol Biol. 2004 Jul 16;340(4):783-95
references.pmid: 15223320
references.citation: Nature. 2006 Oct 5;443(7111):548-52
references.pmid: 17024087
references.citation: Nucleic Acids Res. 2001 May 1;29(9):e45
references.pmid: 11328886
references.citation: Mol Plant Pathol. 2010 Jul;11(4):503-12
references.pmid: 20618708
references.citation: PLoS Genet. 2013 Jun;9(6):e1003272
references.pmid: 23785293
references.citation: J Wildl Dis. 1992 Oct;28(4):532-6
references.pmid: 1474649
references.citation: Mol Immunol. 2007 Feb;44(6):1374-83
references.pmid: 16806477
references.citation: FEMS Microbiol Lett. 2010 Sep 1;310(2):127-37
references.pmid: 20659163
references.citation: Vet Immunol Immunopathol. 1999 Dec 15;72(1-2):203-12
references.pmid: 10614510