title: Enzymes released from Lepeophtheirus salmonis in response to mucus from different salmonids.
abstract: Adult and mobile preadult sea lice Lepophtheirus salmonis were incubated with mucus samples from rainbow trout (Oncorhynchus mykiss), coho salmon (O. kisutch), Atlantic salmon (Salmo salar), and winter flounder (Pseudopleuronectes americanus) to determine the response of L. salmonis to fish skin mucus as assessed by the release of proteases and alkaline phosphatase. There was variation in the release of respective enzymes by sea lice in response to different fish. As well, sealice collected from British Columbia responded differently than New Brunswick sea lice to coho salmon mucus. Fish mucus and seawater samples were also analyzed using protease gel zymography to observe changes in the presence of low molecular weight (LMW) proteases after L. salmonis incubation. Significantly higher proportions of sea lice secreted multiple bands of L. salmonis-derived LMW proteases after incubation with rainbow trout or Atlantic salmon mucus in comparison with seawater, coho salmon, or winter flounder mucus. Susceptibility to L. salmonis infections may be related to the stimulation of LMW proteases from L. salmonis by fish mucus. The resistance of coho salmon to L. salmonis infection may be due to agents in their mucus that block the secretion of these LMW proteases or factors may exist in the mucus of susceptible species that stimulate their release.
authors.affiliation: National Research Council of Canada, Institute for Marine Biosciences, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: M D
authors.initials: MD
authors.lastname: Fast
authors.forename: J F
authors.initials: JF
authors.lastname: Burka
authors.forename: S C
authors.initials: SC
authors.lastname: Johnson
authors.forename: N W
authors.initials: NW
authors.lastname: Ross
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002364:Caseins / Q000378:metabolism; D033342:Copepoda / Q000201:enzymology*; D004198:Disease Susceptibility / Q000201:enzymology / Q000662:veterinary; D004478:Ectoparasitic Infestations / Q000201:enzymology / Q000469:parasitology / Q000662:veterinary*; D010450:Endopeptidases / Q000737:chemistry / Q000378:metabolism; D005393:Fish Diseases / Q000201:enzymology / Q000469:parasitology*; D008970:Molecular Weight; D009093:Mucus / Q000201:enzymology / Q000502:physiology*; D012487:Salmonidae / Q000378:metabolism / Q000469:parasitology*; D012623:Seawater / Q000032:analysis; D013045:Species Specificity
chemical_list: D002364:Caseins; C026018:azocasein; D000469:Alkaline Phosphatase; D010450:Endopeptidases